摘要:

Shell Industrial ChemicalsDetergents andWetting Agents*Lenka*Lensex*Lensine*Lensitol*Lensode1*Nonidet*Teepol*Teepol Anti-Foaming agent*Teepol PowderDetergentIntermediatesDry Cleaning AidGermicidalDetergentFibre LubricantMoth proofingAgentInsecticides*Dobane Alkylates*Elvira*Nonidet 32GOxitex*Dielmoth*Shellcox with Dieldrin*Shelltox AerosolSolventsAcetoneBenzeneDiacetone AlcoholI :2 DichloropropaneEthyl Amy1 KetoneEthylene Glycol Ethers(*Oxitol, *Dioxitol and*Trioxito1 Solvents)Ethylene Glycol EtherAcetatesHexylene Glycollsopropyl Alcohol (IPSlsopropyl EtherMethyl Ethyl KetoneMethyl lsobutyl CarbinolMethyl lsobutyl KetonePent-Oxone and Pent-0x01Secondary Butyl AlcoholGrades)*Shellsol hydrocarbonsol ventsTolueneXyleneSynthetic ResinsCuring Agents*Epikote Resins*Epikure(For *Epikote Resins)IntermediatesAllyl AlcoholAllyl CholorideAnt i-Stat ic Add i rivep-t Butylbenzoic AcidDi-isobutyleneDiphenylolpropane*Dutrex ProductsEpichlorhydrin*Ionex*Alphano1 79Naphthenic AcidsNonanolPetroleum SulphonatesShell Water Finding PasteSulphurTertiary Butyl AlcoholCorrosion InhibitorHigh Vacuum Oils,Greases and WaxesV.P.I.2SOf2SO*Apiezon Gradesfor high vacuum workGeneral ChemicalsBicycloheptadieneCalcined CokeDiethanolamineDiethylene GlycolDiisopropanolamineDipropylene GlycolEthylene OxideMicrocrystalline WaxMixed lsopropanolaminesMonoethanolamineMonopropylene GlycolParaffin WaxPitchPolyether TriolsPolyethylene Glycols(Liquids and Solids)Polypropylene GlycolsPropylene OxideStyrene MonomerTriethanolamineTriethylene GlycolTriisopropanolamine*Oxil u besShell Plastics and Rubbers*Carina P.V.C.*Carlona Low Density *Cariflex Styrene Butadiene*Carlona P. Polypropylene Polyethylene Rubbers*Carlona High Density *Styrocell Expandable and *Cariflex Isoprene RubbersPolyethylene Expanded Polystyrene *Carinex PolystyreneShell Chemical Company LimitedMarlborough House,15-17 Gt. Marlborough Street, London, W.1*Registered Trade MarksVIBRATION MILLS AND VIBRATION MILLINGby H. E. ROSE and R. M. E. SULLIVAN.Ex. Cr. tho. Illustrations. 250 pp. 25s.APPLIED PETROLEUM RESERVOIR ENGINEERINGby B. C.CRAFT and M. F. HAWKINS, JR.The growth of the petroleum industry demands improved scientificmethods for the analysis and prediction of oil reservoir and wellperformance. This book is a significant contribution to thissubject, which now constitutes a well-defined, highly technicalbranch of petroleum engineering.Med. 8vo. 437 pp. Illustrated. 62s. 6d.FUNDAMENTALS OFCHEMICAL mGINJ3ERING OPERATIONSby M. G. 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ISSN:0365-6217    

DOI:10.1039/AR96057FP001

出版商:RSC    

年代:1960

数据来源: RSC

摘要:

ANNUAL REPORTSON THEPROGRESS OF CHEMISTRYGENERAL AND PHYSICAL CHEMISTRY1. GENERAL INTRODUCTIONTHE General and Physical Chemistry Section adopts again the form used inthe last two years. The sub-sections attempt to cover, in the main, partsthat were not dealt with last year; this involves to some cxtent a return tothe subjects of 1958. Last year for instance there was a report on Ramanspectra. This year there is one on spectroscopy and molecular structurewhich is more concerned with the infrared region. In the field of ionicsolutions there are two reports, the first being a general one devoted tonewer techniques, results of particular precision, and recent theoreticalwork; the other reviews work on fast reactions in solution which constitutesa relatively recent development.In 1959 there was a report on nuclearmagnetic resonance; this year there is one on electron spin resonance stressingmainly the chemical aspects of the work. There is also a general report onoptical, electrical, and magnetic properties. This deals with such topics asdipole moments, dielectric saturation, electric quadrupole moments, mag-netic susceptibilities, polarisabilitics, etc. Last year there were two sectionsdevoted to reaction kinetics; this year there is only one and this surveysthe work that has been carried out 011 unimolecular gas-phase reactionspresenting both the theoretical and experimental aspects. It is three yearssince there was a report on thermochemistry so one is included now. Itdescribes developments in the measurement of heats of combustion and ofheats of reactions involving fluorine.In the remaining section, studies ofthe physical properties of polymers both in bulk and in solution are pre-sented. This is a subject on which very few reports have appeared and itwas felt that one was needed.J. W. L.2. THERMOCHEMISTRYTHIS Report is concerned primarily with recent progress in experimentalthermochemistry-Le., with the measurement, usually by calorimetricmethods, of heats of chemical reactions and of the chemical thermodynamicproperties of substances. Emphasis is laid on work published in 1960, butin view of the lapse of three years since the previous Report on this topic,reference is made to some of the major developments over this longer period.H. Mackle, A m .Reports, 1957, 54, 718 GENERAL AND PHYSICAL CHEMISTRY.Heats of Combustion in Oxygen.-There are three established experi-mental techniques for making accurate measurements of heats of com-bustion. These are : (i) conventional, or “ static ” bomb calorimetry,(ii) ‘‘ rotating ” bomb calorimetry, and (iii) flame calorimetry.The first method is satisfactory for the study of compounds which burncleanly to give well-defined products in defined thermodynamic states.The rotating bomb calorimeter was developed to deal with the more diffi-cult problem presented by compounds which burn to produce an inhomo-geneous mixture of products that are badly-defined from the thermodynamicpoint of view. The rotating bomb permits the measurement of the heatof two processes in a single experiment-(a) the combustion of the sub-stance, followed by (b) the solution of the products in a suitable solvent,ending finally with a homogeneous mixture of products in solution.Thesolvent is usually water, but may be an oxidizing or a reducing solution,depending on the composition of the compound to be burnt. The flamecalorimeter is the recognized apparatus for measuring the heats of com-bustion of gases and of volatile liquids: it has been used to measure com-bustion heats of several hydrocarbons, and of a few organic oxygen andnitrogen-cont aining compounds.The static bomb calorimeter is generally satisfactory for combustionstudies on hydrocarbons and on organic compounds containing oxygen andnitrogen. It is also satisfactory for measuring the heats of combustion ofmetals, metal nitrides, and metal carbides, provided that a complete analysisof products can be made and that combustion is complete.The conven-tional method is far less satisfactory when applied to combustion of organo-sulphur compounds, organic halides, and organometallic compounds : forthese types of compound, reliable rotating-bomb techniques are becomingavailable.Three recent papers from the Chemical and PetroleumResearch Laboratory a t Pittsburgh report measurements of heats of com-bustion on pure hydrocarbons.have investigated the cis- and the trans-form of 9-methyldecalin, findingthe tram-isomer to be the more stable by 1.39 & 0.64 kcal./mole.Thesame paper also refers to new measurements by Speros and Rossini on thecombustion heats of cis- and trans-decalin, which showed the trans-isomerto be more stable than the cis-form by 2.69 & 0.31 kcal./mole. The datasupport the conformational concepts of Turner: whose predicted values forthese isomerization heats are in substantial agreement with the new findings.Browne and Rossini 4 have measured the heats of combustion of the cis-and the frans-isomer of hexahydroindane, and found the trans-isomer morestable by 1-04 & 0.53 kcal./mole. This is less than might initially beexpected-but, as Eliel and Pillar have pointed out, the fusion of the five-membered ring through two equatorial bonds to the six-membered ringHydrocarbons.Dauben, Rohr, Labbauf, and Rossinia W.G. Dauben, 0. Rohr, A. Labbauf, and F. D. Rossini, J . Phys. Chem., 1960,a R. B. Turner, J . Amer. Chem. Soc., 1952, 74, 2118,64, 283.C . C. Browne and F. D. Rossini, J . Phys. Chem., 1960, 64, 927.E. L. Eliel and C. Pillar, J . Amer. Chem. Soc., 1955, 77, 3600SKINNER : THERMOCHEMISTRY. 9involves a considerable distortion which increases the strain in the trans-isomer relative to the cis-form.The heats of combustion of n-decylcyclopentane, n-decylcyclohexane,n-decylbenzene, and hexadec-l-ene are reported by Loeffler and Rossini.6These new data have confirmed that the increment per methylene group inthe heat of combustion for higher members of the ut-alkyl series of hydro-carbons is substantially constant (mean value AHao per CH, = -156.29 &0.07 kcal./mole) and in agreement with the figure given earlier by Fraser andProsen.,The thermodynamic properties, including heats of combustion, ofindane and indene, have been investigated by Stull, Sinke, McDonald,Hatton, and Hildenbrand.* Combining the heats of formation obtainedwith those of Browne and Rossini 4 for cis- and trans-hexahydroindane, onederives the following heats of hydrogenation (reactants and products in theliquid state at 25" c) :indene _+ cis-hexahydroindane: AH = -67.80 $- 0.66 kcal.indene trans-hexahydroindane: AH = -68-54 & 0.70 kcal.indane - cis-hexahydroindane: AH = -43.97 -& 0.83 kcal.indane + trans-hexahydroindane: AH = -44.71 & 0.87 kcal.It is interesting to compare these figures with directly measured heats ofhydrogenation, reported over 20 years ago by Dolliver, Gresham, Kistia-kowsky, and V a ~ g h a n , ~ for indene and indane in the vapour phase at 82" c(AH = -69.9 and -45.8 kcal./mole, respectively).The heats of combustion of the cycloalkanes from C,, to C,, inclusivehave been measured by van Kamp,lo in continuation of the investigationby Kaarsemaker and Coops l1 on the cycloalkanes from C, to C,.The mainconclusions from these studies were :(i) the chair form of cyclohexane is strain free;(ii) all cyclanes with more than 6 carbon atoms are strained to somedegree ;(iii) cyclanes with from 8 to 11 carbon atoms are considerably strained,the greatest strain occurring in C, and C,, rings.There is anappreciable reduction in strain when the ring size reaches 12 carbonatoms.The heats of combustion of three 2-alkyl-1, l-dimethylcyclopropanes(alkyl = ethyl, propyl, and hexyl) have been reported; l2 results are alsoM. C. Loeffler and F. D. Rossini, J . Phys. Chem., 1960, 64, 1530.7 F. M. Fraser and E. J. Prosen, J . Res. Nat. BUY. Stand., 1955, 55, 329.8 D. R. Stull, G. C. Sinke, R. A. McDonald, W. E. Hatton, and D. L. Hildenbrand,Symp. on Thermodynamics, Wattens, 1959, paper 48. For a report on this symposium,see H. A. Skinner, K. Schafer, and J. S. Rotdinson, Nature, 1959, 184, 1606.9 M. A. Dolliver, T. L. Gresham, G. B. Kistiakowsky, and W. E. Vaughan, J . Amer.Chem. SOC., 1937, 59, 831.lo H. van Kamp, Diss., Amsterdam, 1957; J.Coops, H. van Kamp, W. A. Lam-bregts, B. J. Visser, and H. Dekker, Rec. Trav. chim., 1960, 79, 1226.l1 Sj. Kaarsemaker and J. Coops, Rec. Tyav. chim., 1952, 71, 261.12 0. N. Kachinskaya, S. K. Togoeva, A. P. Meshcherijakov, and S. M. Skuratov,Doklady AKad. Nauk S.S.S.R., 1960, 132, 11910 GENERAL AND PHYSICAL CHEMISTRY.available on the combustion heats of nine branched-chain paraffins contain-ing from 9 to 15 carbon atoms.13 These studies form part of an extensiveprogramme on the thermochemistry of hydrocarbons being undertaken bySkuratov and his group at the Luginin Thermochemistry Laboratory,Moscow.Compounds contai&g carbon, hydrogen, and oxygen. A critical reviewby Rossini l4 in 1934 gave values for the heats of formation of liquid andgaseous normal alcohols from methanol to n-decanol inclusive. Thesehave been generally accepted until recently, but have now been reconsideredand revised by Green.15 The revised values differ appreciably from theearlier figures, especially for the higher alcohols, but they still depend, inpart, on heats of combustion measured over 30 years ago, and new measure-ments on alcohols would be welcome.Recent studies indicate a recognitionof this need, and values have now been reported for the heats of com-bustion of the four isomeric butyl alcohols by Skinner and Snelson,16 ofn-butyl alcohol and of 2-ethylhexanol by Tjebbes,17 and of 3,5,5-trimethyl-hexanol by Nicholson.l8 Skinner and Snelson's data- lead to the followingheats of isomcrization (in the gas-phase at 25" c) :(i) n-butanol- isobutanol: AH = -1.6 & 0.7 kcal./mole.(ii) n-butanol _t s-butanol: AH = -4.0 & 0.7 kcal./mole.(iii) n-butanol- t-butanol: AH = -8.8 -+ 0.7 kcal./mole.Evans, Fairbrother, and Skinner19 have pointed out that the hcats ofisomerization of processes of the types (ii) and (iii) in RX compounds seemto be larger the more electronegative the group X, but the reason for this isnot yet clear.The heats of combustion of phenol, the three cresols, and the six xylenolshave been measured at the National Chemical Laboratory, Teddington.20The combustion data, combined with heats of sublimation measured byBaddiscombe and Martin,21 provided the standard heatsof formation in the gaseous states: Cox has made use of( A ) these and of the bond-energy scheme suggested byLaidler,22 to calculate " resonance energies " in thesecompounds.He concluded that thc resonance energies are larger than inbenzene or toluene, attributing this to the additional stability due to theresonance contribution of quinonoid forms, e.g., A (inset).An extensive investigation on the normal fatty acids and their methylesters has been carried out by Adriaanse 23 at the Free University, Amster-53 S. M. Shtexer, S. h1. Skuratov, V. K. Daukshas, and R. Y. Levina, Doklady Akad.14 F. D. Rossini, J , Res. Nut. Bur. Stand., 1934, 13, 189.15 J. H. S. Green, Chem. and Ind., 1960, 1215.16 H. A. Skinner and A. Snelson, Trans. Faraday SOL, 1960, 56, 1776.17 J. Tjebbes, Acta Chern.Scand., 1960, 14, 180.0 6 , ~Nauk S.S.S.R., 1959, 127, 812.G. R. Nicholson, J., 1960, 2378.F. W. Evans, D. M. Fairbrother, and H. A. Skinner, Trans. Faraday Soc., 1959,2o R. J. L. Andon, D. P. Biddiscombe, J. D. Cox, R. Handley, D. Harrop, E. F. G.2* D. P. Biddiscombe and J. F. Martin, Trans. Faraday SOL, 1958, 54, 1316.22 I<. J. Laidler, Canad. J . Chern., 1956, 34, 626.23 N. Adriaanse, Diss., Amsterdam, 1960.55, 399.Herington, and J. F. Martin, J . , 1960, 5246SKINNEII : THERMOCIIEMISTHY. 11dam. Values are reported for the heats of combustion of the liquid (C,-C,)and solid (Clo--C20) fatty acids, and the liquid methyl esters (C5--CI5 in-clusive): measurements of the heats of fusion of the acids were also made.The increment in the standard enthalpy of combustion of the liquids permethylene group proved to be constant and the same in the acids as in themethyl esters.New measurements have also been reported recently onthe heats of combustion of liquid formic acid 24 and liquid acetic acid.25Colomina, Perez-Ossorio, and Boned 26 have measured the heats ofcombustion of the solid o-, nz-, and 9-toluic acids: their results showed thepara-isomer to be the most stable, and the orlho-isomer the least stable ofthe three.Very few accurate heats of combustion data have been available untilrecently on aliphatic aldehydes-but now Tjebbes l7 has reported combustionstudies on butanal, but-2-enal, 2-ethylhexanal, and 2-ethylhex-2-ena1,and Nicholson 27 on butanal and heptanal. The aldehydes proved difficultcompounds to deal with, largely because of their hygroscopic nature.BothTjebbes and Nicholson were unable to obtain completely anhydrous aldehydesamples for combustion measurements, and the results needed correction toallow for retained water.Colomina, Latorre, and Perez-Ossorio 28 have measured the heats ofcombustion of five liquid alkyl phenyl ketones (alkyl = methyl, ethyl,propyl, isobutyl, and t-butyl) : the increments in the heats of combustionin ascending the series from methyl to isobutyl phenyl ketone were notunusual, but the difference in the combustion heats of isobutyl and t-butylphenyl ketones indicated that the former is the more stable by 2.7 kcal./mole.This implies strong steric repulsion between the bulky t-butyl group and thephenyl group in t-butyl phenyl ketone.Estimates of the energy difference between the boat and the chair formof cyclohexane have ranged from 1-3 to 10.6 kcal./mole, but a recent experi-mental evaluation has greatly reduced the uncertainty, giving this difference(at 25" C, vapour phase) as 5.3 & 0.3 kcal./mole. The method used was todetermine the energy difference between the lactones of 2eq-carboxymethyl-3eq-hydroxy-tram-decalin and 2ax-carboxymethyl-3ax-hydroxy-tmns-deca-lin from measurements of heats of combustion and Knudsen-effusionvapour-press~res.~~ In the lactone (l), the central ring has the chairform, whereas in lactone (2) the ring is constrained to adopt the boat form.Confirmation of this value of the energy difference is provided by studiesof the equilibrium between the cis- and the trans-isomer of 1,3-di-t-butyl-cyclohexane by Allinger and Freiberg30 Of these isomers, only the cis-form can comfortably adopt the chair conformation, the trans-form being24 G.C . Sinke, J . Phys. Clzem., 1959, 63, 2063.26 F. W. Evans and H. A. Skinner, Trans. Furaduy SOC., 1959, 55, 260.26 M. Colomina, R. Perez-Ossorio, and M. L. Boned, Symp. on Thermodynamics,27 G. R. Nicholson, J., 1960, 2377.28 M. Colomina, C. Latorre, and R. Perez-Ossorio, Symp. on Thermodynamics,29 W. S. Johnson, J. L. Margrave, V. J. Bauer, M. A. Frisch, L. H. Dreger, and30 N. L. Allingcr and L. A. Freiberg, J . Amer. Chem. SOC., 1960, 82, 2393.Wattens, 1959, paper 22b.Wattens, 1059, paper 22a.W.N. Hubbard, J . Amcr. Chem. SOC., 1960, 82. 125512 GENERAL AND PHYSICAL CHEMISTRY.forced into the boat in order to avoid very severe steric repulsion betweenthe t-butyl groups. From the variation of the equilibrium constant withHtrans-syn-trans trans-anti-transtemperature, the values AH = 5.9 5 0.6 kcal./mole, A S = 4.9 e.u., forthe cis+ trans interconversion were derived. Mention should also be madeof a recent determination 31 of the energy of activation for the chair+chairinterconversion of cyclohexane, based on measurements of the rate-constantfrom studies of nuclear magnetic resonance spectra.Reliable values for the heats of form-ation of methylamine, dimethylamine, and trimethylamine and for ethyl-amine, diethylamine, and triethylamine are now available following newmeasurements of the heats of combustion by Jaffe.32 The heats of com-bustion of n-, s-, and t-butylamines have also been redetermined recentlyby Evans, Fairbrother, and Skinner.lg Measurements of the chemicalthermodynamic properties , including heat of combustion, of pyrrolidinehave been made independently by two groups of worker^,^^^^^ the resultsbeing in excellent agreement. These and similar thermodynamic studieson cyclopentane 35 (and derivatives 36) have established that there is freeor restricted pseudorotation in saturated five-membered rings.The con-formation and strain energy in cyclopentane and derivatives have beendiscussed theoretically by Pitzer and Donath?’ and estimates made of thebarriers hindering pseudorot ation,The heats of combustion of a number of crystalline amino-acids arereported by Tsuzuki, Harper, and Hunt,38 from which heat of formationdata were obtained for L-phenylalanine, L-tryptophan, L-isoleucine, L-threonine, L-alanine, glycine, and L-methionine.The heats of combustion of pyridine, the three picolines, and the sixlutidines have been measured at the National Chemical Laboratory, Ted-d i n g t ~ n .~ ~ . ~ ~ Accurate vapour-pressure and vapour-compressibility mea-Organic compomds of nitrogen.F. R. Jensen, D. S. Noyce, C. H. Sederholm, and A. J. Berlin, J . Amer. Chem. SOL,32 I . Jaff6, MSc. Thesis, Maryland, 1958.33 D. L. Hildenbrand, G. C. Sinke, R. A. McDonald, W. R. Kramer, and D. R. Stull,J .Chem. Phys., 1959, 31, 650.34 J. P. McCullough, D. R. Douslin, W. N. Hubbard, S. S. Todd, J. F. Messerly,I. A. Hossenlopp, F. R. Frow, J. P. Dawson, and G. Waddington, J . Amer. Chem.SOC., 1959, 81, 5884.35 J. P. McCullough, R. E. Pennington, J. C. Smith, I. A. Hossenlopp, and G. Wad-dington, J . Amer. Chem. SOC., 1959,81, 5880.36 D. W. Scott, W. T. Berg, and J. P. McCullough, J . Phys. Chem., 1960, 84, 906.37 K. S. Pitzer and W. E. Donath, J . Amer. Chem. SOC., 1959, 81, 3213.s8 T. Tsuzuki, D. 0. Harper, and H. Hunt, J . Phys. Chem., 1958, 62, 1594.40 J. D. Cox and H. A. Gundry, J., 1968, 1019.1960, 82, 1256.J. D. Cox, A. R. Challoner, and A. R. Meetham, J., 1954, 26624 GENERAL AND PHYSICAL CHEMISTRY.introduced by Jakuszewski and Lazniewski: 145 studies were made on thethermokinetics of enolization, and the heats of enolization of pdiketoneswere determined.The method of heat-burst microcalorimetry, and applic-ations of it, were reviewed recently.l46The heats of addition of diborane gas to olefins to form boron trialkylshave been briefly reported by Bennett, Pedley, and Skinner.14' The hydro-boration reactions were carried out in solution in diethylene glycol dimethylether at room temperature: these reactions take place rapidly and themeasured heats provide an indirect route to the heats of formation of borontrialkyls. A preliminary report has also appeared on measurements byJackman and Packhaml& of the heats of hydrogenation of a number ofaldimines; an interesting aspect of this study was the use of lithium alu-minium hydride in bis-2-ethoxyethyl ether as hydrogenation agent.Reaction Heats from Equilibria Studies.-Valuable thermodynamic datahave been obtained in the last decade by the combined use of the Knudseneffusion cell and the mass spectroscope to measure the chemical compositionand temperature-pressure behaviour of the vapours escaping from thereaction mixture contained in the high-temperature cell.Many of thesestudies have involved reactions of inorganic oxides ; typical are three recentstudies from the University of Chicago. In one of these, De Maria, Burns,Drowart, and Inghram 149 investigated the vapours from the mixturesMo-Al,O,, U-Al,O,, and W-Al,O,, measuring the partial pressures of thespecies MOO, MOO,, MOO,, WO, WO,, WO,, UO, UO,, and UO,.Valueswere derived for the heats of atomization of each of these oxides.A mass-spectroscopic analysis of the vapour in thermodynamic equili-brium with MOO, a t 1600" K showed the abundance of species,150 MOO, >Mo,06 > MOO, > Mo,Og. The heat of vaporization of solid MOO,, and theheats of dimerization and trimerization of gaseous MOO, were determined.In another study,l5l the vapour from alumina was investigated by the massspectrometer, and the partial pressures of the species A10, A1,0, and A1,0,measured. The heats of atomization of each of these molecules weredetermined.Porter and Zeller 152 have investigated the mass spectra of vapours fromaluminium trichloride and tribromide, describing the association reactions inthe vapour phase: evidence for the presence of the trimer (AlCl,), is pre-sented.The vapour of aluminium trifluoride contains the dimer (AlF,),,and the heat of the dissociation Al,F, ---t ZAlF, was determined. Themass spectra of vapour from a LiF-AlF, mixture showed the presence ofthe complex LiF,AlF,: this is a stable complex, the dissociation145 B. Jakuszewski and M. Lainiewski, Bull. acad. polon. S C ~ . , 1959, 7, 307, 541.146 C. Kitzinger and T. M. Benzinger, Methods Biochem. AnaZysis, 1960, 8, 309.147 J. E. Bennett, J. B. Pedley, and H. A. Skinner, Symp. on Thermodynamics,148 L. M. Tackman and D. I. Packham, Proc. Chem. Soc., 1957, 349.Wattens, 1959, paper 3.14g G. DeMaria, R. P. Burns, J.Drowart, and M. G. Inghram, J. Chem. Phys., 1960,150 R. P. Burns, G. De Maria, J . Drowart, and R. T. Grimley, J. Chem. Phys., 1960,151 J. Drowart, G. De Maria, R. P. Burns, and M. G. Inghram, J . Chem. Phys., 1960,152 R. F. Porter and E. E. Zeller, J . Chew. Phys., 1960,38,858.32, 1373.32, 1363.32, 1366SKINNER : THERMOCHEMISTKY. 25LiF,AlF,+ LiF + AlF, requiring 73 kcal./mole at 1000" K. The stabili-ties of the diatomic molecules BiSe, BiTe, SbTe, and SeTe have been deter-mined by Porter and Spencer from mass-spectral identification of vapourspecies escaping an effusion cell containing Bi,Se,, Bi,Te,, Sb,Te,, andSe-Te.The Knudsen effusion method was used by Searcy and TharplM tomeasure the partial pressures of silicon in the vapours from Mo,Si, Mo,Si,,and MoSi,.The experimental data, together with a new determination ofthe heat of sublimation of silicon,155 have provided the heats of formationof the three molybdenum silicides in the gas phase. A study of the reactionB,O, (1) + C (s) _j_ B20, (g) + CO (g) in the temperature range 1350-1650" K is described by Rentzapis, White, and Walsh: 156 below 1550", onlyvery small quantities of B,O, were formed, but above 1600", the vapourcontained sufficient B,02 to permit measurement of the CO : B202 ratio.The heat of formation of gaseous B,O, was derived.Stubbles and Richardson 15' have used a radiochemical method to studyequilibria between gaseous mixtures of hydrogen and hydrogen sulphideand solid lower sulphides of molybdenum (mixtures of Mo-Mo,S, andMo,S,-MoS,) at 850-1200" c.The standard free energies of formationof Mo~S, and MoS, were obtained, and an estimate made of the standardheat of formation of solid MoS,. The free energy and heat of formationof ThF, (s) has been reported by Darnell,158 from measurements of the equili-brium pressures of silicon tetrafluoride in the reaction Th, (s) + SiO, (s) +Tho, (s) + SiF, (g) in the temperature range 871-995" K. The heat ofdissociation of gaseous Tho has been estimated from the pressure of Thovapour over Th-Tho, mixtures.159The decomposition pressures in the range 908-1057" K of Th(S04), --tTho, + 2 S 0 , (g) + 0, (g) have provided 160 the free energy and heat offormation of solid thorium sulphate. Dissociation pressures of RuCl, (c)a t 650-839" c lead to an estimated heat of formation in fair agreementwith the calorimetrically measured value.143 Decomposition pressures ofthe thiocarbonates Zn(NH,),CS, and Ni(NH,)&S, have been measured byGattow,16, who has also 163 investigated the decomposition of Tl,CO, (275-320" c), T12CS, (110-145" c), and BaCS, (320-360" c).The redistribution reaction BCl, + BF, __, BF,C1 + BFCl, was studiedspectrophotometrically in the range 1 5 4 5 " c by Gunn and Sanborn : 164the forward reaction is endothermic to the extent of ca.1 kcal./mole.153 R. F. Porter and C. W. Spencer, J . Chem. Phys.,1960,32,943.lS4 A. W. Searcy and A. G..Tharp, J. Phys. Chem., 1960, 64, 1539.l55 S. G. Davis, D. F. Anthrop, and A. W. Searcy, J. Phys.Chem. (in press) : cf. ref.156 P. Rentzapis, D. White, and P. N. Walsh, J . Phys. Chem., 1960, 64, 1784.15' J. R. Stubbles and F. D. Richardson, Trans. Faraday SOC., 1960, 56, 1460.158 A. J. Darnell, U.S. Atomic Energy Commision, NAA-SR-4924, 1960, 1.159 A. J. Darnell, W. A. McCallum, and T. A. Milne, J . Phys. Chem., 1960, 64, 341.l60 S. W. Mayer, B. B. Owens, T. H. Rutherford, and R. B. Serrins, J. Phys. Chem.161 W. E. Bell, M. C. Garrison, and U. Merten, J . Phys. Chem., 1960, 64, 145.162 C. Gattow, Naturwiss., 1959, 46, 72.l63 G. Gattow, Symp. on Thermodynamics, Wattens, 1959, paper 19.164 S. R, Gunn and R. H. Sanborn, J. Chem. Phys., 1960, 88, 955.154.1960, 64, 91126 GENERAL AND PHYSICAL CHEMISTRY.Olander and Sunner 165 made use of gas-chromatographic analysis to in-vestigate the redistribution Me,S, + Et,S, + 2MeEtS,.Heats of Vaporization, Sublimation, and Atomization.-An adiabaticcalorimeter for the direct measurement of heats of vaporization at 25" chas been described by Waid~o.l~~ The calorimeter is designed preferably forcompounds having vapour pressures in the range 5-100 mm.at 25" c: itrequires only small quantities (ca. 200 mg.) of substance per measurement,and an accuracy within limits of 0.5% is claimed. A method of measuringheats of vaporization described by Mackle, Mayrick, and Rooney 167 makesuse of gas-chromatography to determine the quantity of vapour in a givenvolume at fixed temperatures. The ingenious radiochemical method ofmeasuring vapour pressures described by Carson, Stranks, and Wilms-hurst to determine the heat of sublimation of diphenylmercury has beenfurther applied in measurements 169 of the vapour pressures and heats ofsublimation (to S, molecules) of the a-, p-, and y-forms of sulphur.The mass-spectrometer and effusion-cell method has further proved ofvalue in new measurements of the heat of sublimation of boron,170 of uran-ium,149 of silicon 155 (AH::,, = 108.4 3 kcal./mole), and of zinc and cad-inium.l7l Effusion measurements of vapour pressures have been reportedfor CrBr2,172 for FeCl,, FeBr,, and FeI,,173 for solid bromine,17* and forthallous ch10ride.l~~ From measurements of the Langmuir free-evaporationrates, vapour pressures and heats of sublimation were obtained for palladiumand platinum 176 (AH::,, = 91-0 and 135.2 kcal./mole, respectively), and forthorium 159 (AH::,, = 136.6 kcal./mole).New measurements are also avail-able on the heat of sublimation of silver,177 and of the colourless, red, andblack forms of phosph0rus.~~8 Schick 179 has reviewed the thermochemistryof the vaporization of silica at high temperatures.Bond Dissociation Energies, Ionization Potentials, and Electron Affinities.-Estimates of the dissociation energy of C-€I in ethylene have spread overa wide range, from 122 to 92 kcal./mole. The question now seems to havebeen settled by electron-impact measurements by Harrison and Lossing 18*on vinyl radicals produced by decomposition of methylvinylmercury ; thevalue D(viny1-H) = 105 & 3 kcal./mole was obtained by combining thevertical ionization potential (9.45 ev) of the vinyl radical with the appear-165 C.J. Olander and s. Sunner, Symp. on Thermodynamics, Wattens, 1959,paper 18.166 I. Wadso, Ada Chem. Scand., 1960, 14, 566.167 IS. Mackle, R. G. Mayrick, and J. J. Rooney. Tram. Faraday Soc., 1960,56, 115.168 A. S. Carson, D. R. Stranks, and B. R. Wilmshurst, Proc. Roy. Sac., 1958, A ,109 C. Briske, N. H. Hartshorne, and D. R. Stranks, J., 1960, 1200.170 P. A. Akishin, 0. T. Nikitin, and L. N. Gorokhov, Doklady Akad. Nauk S.S.S.R.,171 K. H. Mann and A. W. Tickner, J . Phys. Chem., 1960, 64, 251.172 R. J. Sime and N. W. Gregory, J . Amer. Chern. Soc., 1960, 82, 800.173 R. J. Sime and N. W. Gregory, J . Phys. Chem., 1960, 64.86.174 M. B. Frey and N. W. Gregory, J . Amer. Chem. SOL, 1960, 82, 1068.175 R. F. Barrow, PYOC. Phys. Soc., 1960, '75. 933.176 L. H. Dreger and J. L. Margrave, J . Phys. Chem., 1960, 64, 1323.177 Y. V. Kornev and E. 2. Vintaiken, Chem. Abs., 1960, 54, 19142.178 H. J. Rodewald, Helv. Chem. Actu, 1960, 43, 878.li9 EI. L. Schick, Chem. Rev., 1960, 60, 331.180 A. G. Harrison and F. P. Lossing, J . Amer. Chew SOL, 1960, 82, 519.244, 72.1959, 129, 1075SKINNER : THERMOCHEMISTRY. 27ance potential of vinyl ion from ethylene. The new determination placesthe C-H dissociation energy in ethylene slightly higher than that of C-Hin methane, and a little less than C-H in acetylene 181 [D(H-C,H) - 110kcal./mole].Electron-impact measurements l B 2 on the cyclopentadienyl and cyclo-heptatrienyl radicals have led to the ionization potentials (8.69 ev and6-60 ev, respectively) and to the dissociation energy, D(C,H,-H) = 74 & 7kcal./mole.Values for the ionization potentials of 1- and 2-naphthylmethyland of diphenylmethyl183 agree rather well with calculated values basedon self-consistent molecular-orbital theory.ls4 Electron-impact studies onthe cyanogen halides have been reported by Herron and Dibeler,ls5 fromwhich the electron affinity of the CN radical (74 6 4 kcal./mole) and theheat of formation, AHf(CN) = 89 & 2 kcal./mole, were deduced. The sameinvestigators 186 have remeasured the ionization potential of fluorine, alsoby the electron-impact method.The kinetics of thermal decomposition (toluene carrier-gas technique) ofmethyl phenyl sulphide l87 and of phenylacetic acid and diphenylaceticacid lS8 have been analysed to yield the dissociation energies D(PhS-Me) =60, D(PhCH,-C0,H) = 55, and D(Ph,CH-C0,H) = 52 kcal./mole.Thevalue of D(PhS-Me) suggests that the phenylthio-radical is resonance-stabilized by ca. 13 kcal./mole.Barrow lB9 has listed and compared thermochemical and spectroscopicestimates of the dissociation energies of gaseous monohalides of B, Al, Ga,In, and T1. There appears to be a genuine discrepancy between thermo-chemical and spectroscopic values for D(Al-F), which is considered to bedue to the existence of a potential hump of ca. 11 kcal./mole in the Astate of A1F. The dissociation energies of GeH and SiH have been reportedfrom spectroscopic studies by Barrow and Deutsch.lgOThe electron affinities of atoms have been reliably measured only incomparatively few cases (halogens, 0, C, S), and extrapolation methodsthrough the ionization potentials of isoelectronic ions are commonly used toprovide approximate working data.A recent description by EdEn lgl ofa modified extrapolation procedure seems to represent a considerableadvance on previous extrapolation methods and has been applied to each ofthe elements of the first and second short periods.H. A. S.lR1 F. H. Coates and R. C. Anderson, J . Anzer. Chcm. Soc., 1957, 79, 1340.laZ A. G. Harrison, L. R. Honnen, EL J. Dauben, jun., and F. P. Lossing, J . Amer.A. G. Harrison and F. P. Lossing, J .Amer. Chcm. SOC., 1960, 82, 1052.ls4 N. S. Hush and J. A. Pople, Trans. Faraduy Sac., 1955, 51, 600.la5 J. T. Herron and V. H. Dibeler, J . Amer. Chem. SOC., 1960, 82, 1555.M. H. Back and A. H. Sehon, Canad. J . Chem., 1960, 38, 1076.188 M. H. Back and A. H. Sehon, Canad. J . Chem., 1960,38,1261.lag R. F. Barrow, Trans. Faraday SOC., 1960, 56, 952.lgo R. F. Barrow and J. L. Deutsch, Proc. Chem. Soc., 1960, 122.lgl B. Edle'n, J. Chem. Phys., 1960, 33, 98.Chem. SOC., 1960, 82, 559328 GENERAL AND PHYSICAL CHEMISTRY.3. UNIMOLECULAR GAS-PHASE REACTIONSTHIS report attempts to cover the major theoretical and experimentalwork in this field published in 1959 and 1960. The literature survey wascompleted in December.Theory of Unimolecular Reactions.-Much important theoretical workhas been published in the past two years.While in many respects a mole-cule undergoing a unimolecular transformation represents the simplestpossible kinetic system, the theories of such reactions are in some waysmore difficult than those relating to kinetically more complex systems. Itis therefore most helpful to have many of the problems of unimolecularreaction theory critically discussed in a book by Slater,l which also containsa detailed exposition of his own original contributions to the subject. Inthe past, most experimental work on unimolecular reactions has been dis-cussed in terms of two types of theories. The first type is associated withthe names of Hinshelwood,2 Ka~sel,~ and Rice and Ramsperger: and thesecond type is due to Slater.5 In the first-type theory, energy in an energisedmolecule is assumed to flow freely between some or all of the normal modes ofthe molecule, whereas in Slater’s theory such energy flow is forbidden.These theories are essentially “ classical theories ” and such quantummodifications as have at times been suggested have either been ratherunrealistic or have been of little use for numerical calculations.Recentlyincreasing use has been made of equations developed by Marcus,6* usingabsolute rate theory. This is essentially a quantum theory, though semi-classical approximations may be made in its application, to ease some ofthe computational difficulties. Rabinovitch and his co-workers 899 haveinterpreted their results on the life-times of excited molecules using thisquantum formulation.Marcus and Wieder lo have applied the quantumtheory to existing unimolecular rate data and computed the error presentwhen classical theory is used. They find that in the calculation of thelimiting low-pressure rates and of the plots of pressure against kt/ka, theerror is temperature-dependent and increases from a factor of 3 for smallmolecules such as ozone to 30 or more for more complex molecules such ascyclopropane and ethane (under typical experimental conditions). UnlikeHinshelwood’s* and Slater’s theories all vibrations are assumed to be“ active ”.In an important series of papers Gill and Laidler have carried out a* Throughout the remainder of this text this “ composite theory ” is referred to1 N.B. Slater, “ Theory of Unimolecular Reactions,” Methuen, London, 1959.simply as Hinshelwood’s theory; this is solely for convenience.-ED.C. N. Hinshelwood, Proc. Roy. Soc., 1927, A, 113, 230.L. S. Kassel, J . Phys. Chem., 1928, 32, 225.0. K. Rice and H. C. Ramsperger, J . Amer. Chern. SOL, 1928, 50, 617.ti N. B. Slater, Proc. Roy. SOL, 1948, A , 194, 112.R. A. Marcus and 0. K. Rice, J . Phys. Colloid Chem., 1951, 55, 894.R. A. Marcus, J . Chem. Phys., 1952, 20, 359.B. S. Rabinovitch and R. W. Diesen, J . Chem. Phys., 1959, 30, 735.R. E. Harrington, B. S. Rabinovitch, and R. W. Diesen, J . Chem. Phys., 1960,lo G. M. Wieder and R. A. Marcus, Abs. of Papers, Amer. Chem. SOC. 138th Meeting,32, 1245.1960FREY: UNIMOLECULAR GAS-PHASE REACTIONS.29complete vibrational analysis of the hydrogen peroxide and the ozonemolecules.11,12 They calculate the second-order rate constant (i.e., the rateof energisation of the molecules) for hydrogen peroxide according to Slater’stheory and find it too low compared with the experimental value. TheHinshelwood-theory value gives good agreement if five of the six normalmodes are treated as active. For ozone Slater’s theory gives a value forthe rate of energisation close to the experimental one whereas the rate byHinshelwood’s theory is too large by a factor of 3. This discrepancy is nothowever great; choice of a somewhat different collision diameter (and re-membering the experimental uncertainties in the value of the energy ofactivation for this reaction) could easily give agreement with Hinshel-wood’s theory.It should be remarked that Marcus’s formulation agreeswith the experimental value for ozone though the calculated value forhydrogen peroxide is considerably lower than the experimental value.From their examination of the data for the low-pressure rate constants forthe decomposition of 0,, N20, H20,, N,O,, C2H6 (into two methyl radicals),cyclopropane, and ethyl chloride, Gill and Laidler l3 conclude that for N20,H202, and c2H6 Slater’s theory yields rates of energisation which are toolow whereas the values by Hinshelwood’s theory are satisfactory; for O,,N205, cyclopropane, and C,H,Cl Slater-theory values are reasonable butthose by Hinshelwood’s theory are too large unless significantly fewerdegrees of freedom than are actually in the molecule are used.Theseresults are explained on the hypothesis that Slater’s theory is correct as faras break-down of energised molecules A* is concerned, but not necessarilywith regard to their rate of formation. The following scheme is suggested:k1H A +A=A’+ AA* + A+”.’ProductsThe steady-state treatment of these equations gives a complicated expressionof the overall rate of reaction which simplifies at sufficiently high pressures toThus Slater’s expression for the high-pressure rate will apply, even if k,is large. At very low pressuresZJ = (K,’ + k1”)A2which, since kIH is probably always much larger than kls, becomes equal tothe rate according to Hinshelwood’s theory.Reasons are advanced whyl1 E. K. Gill and K. J. Laidler, Proc. Roy. SOL, 1959, A , 251, 66.l 3 E. I<. Gill and I<. J. Laidler, Proc. Roy. SOC., 1959, A , 250, 121.E. K. Gill and K. J. Laidler, Trans. Faraday SOC., 1959, 55, 75330 GENERAT, AND PHYSICAL CHEMISTRY.the intramolecular flow of energy would tend to be more rapid in smallermolecules (on both classical and quantum grounds), though in this respectozone appears to be anomalous. Owing to the complexity of the nitrousoxide reaction,14 too much significance should not be attached to the relateddata in this case.Thiele and Wilson l5 have tested Slater’s theory by comparing theoreticaland experimental values of the pressure at which the rate constant hasfallen off from the high-pressure limit by 5%.Agreement with experimentaldata on cyclobutane, cyclobutene, and nitrogen pentoxide is poor, thoughthe discrepancy in the case of the last compound is probably not serious.has shown that if a molecule has quantised energy and can onlydissociate if it has more than a critical energy, then the only molecular modelgiving the Arrhenius form for the first-order rate constant is that of a systemof degenerate harmonic oscillators, similar to Kassel’s models. If themolecular energies are effectively classical and continuous the Arrheniusequation is much less restricting as regards possible models. Slater’s classi-cal expression for the high-pressure rate of a unimolecular reaction has beenextended to cover the case where reaction occurs owing to the simultaneousextension of two “ critical ” co-ordinates. The results are applied to thedecomposition of cyclobutane with which there is no agreement.l7 Thisextension has also been treated by the method of the transition state.l* Anextension of the Kassel model to one where the energy is required only to belocalised in 2 (2 > 1) oscillators yields the possibility of considerably higherfrequency factors.lg The pressure dependence of the first-order rate con-stant has been examined within the framework of the generalised Lindemannmechanism.2* The effect of inefficient stepwise activation in combinationwith the simple Kassel microscopic decomposition frequency is examined.Inefficient intermolecular energy transfer tends to broaden the transitionrange of k between the high- and the low-pressure limit as does the effect ofanharmonicities in intramolecular energy transfer.Wilson 22 has developeda general method for handling intra- and inter-molecular energy transferand chemical decomposition in unimolecular reactions. The method isapplied to two simple models and it is shown that weak intramolecularcoupling between oscillators representing the reactant molecule leads to atransition region for the rate constant broader than that predicted byKassel’s theory. Kassel’s and Slater’s classical expressions for klk, as afunction of pressure are formally similar and, as pointed out by Slater,l willgives curves of the same slope for FZ = 2s - 1, where PL is the effective num-ber of vibrational modes in Slater’s theory and S the effective number ofoscillators in Kassel’s theory.The major approximation made to obtainthis relation is to replace (b + x) in Kassel’s expression by b, where b =Eo/RT and x = ( E - E,) /RT. The relation is a limiting: one and strictlyMILLS : SPECTROSCOPY AND MOLECULAR STRUCTURE. 45reported the ultraviolet resonance spectrum of the iodine molecule,30 anddeduced very complete vibration-rotation constants for the ground elec-tronic state. Thorough vacuum ultraviolet studies are reported for fluorineand chlorine molecule^.^^Complete progressions of vibrational levels are now known for a numberof diatomic molecules, often in several different electronic states.Whenthe rotational constant B, is also known for the vibrational levels it is inprinciple possible to deduce the form of the internuclear potential function,Recently a number of such calculations have been made by the Rydberg-Klein-Rees method: 32 this is a method based on a W.K.B. phase-integralapproximation, which is relatively easy to apply, and appears to give moreaccurate results than have yet been obtained by fitting any analyticalpotential function to experimental data. Essentially identical curves havebeen calculated for lithium hydride from independent data on lithiumhydride and deuteride.33 The molecules to which this method has beenapplied so far include H,,32 LiH,= HF,M N,, NO, and 0,,35 C0,36 and I,; 3othe work is of interest since it is one more step towards bridging the gapbetween experimental measurements and quantum-mechanical calcul-at ions.Small polyatomic molecules.As mentioned above, the electronic spectraof the methyl and the methylene radical have recently been observed byHerzberg and his co-~orkers,7~37 as the culmination of a long search, inabsorption in the flash-photolysis products of dimethylmercury and diazo-methane, respectively. The methylene radical is particularly interesting,as spectra were observed from both of the expected low-lying electronicstates: 38 32g- in which the molecule is linear and IA, in which it is non-linear, and it was found that the proportion of molecules in the 32 to thosein the IA state-as observed from their spectral intensities-could be variedby adding an inert gas to the diazomethane in the flash tube.The questionas to which is the true ground state was not decided.The NH, radical, previously known from its electronic spectrum,6 hasbeen observed in absorption in the infrared region under low resolution usinga rapid-scan spectrometer to study the flash-photolysis products of hydr-azine.= Also, the infrared spectra of an ammonia-oxygen flame and of apure hydrazine flame have been studied under much higher resolution,4°and although problems of overlapping bands and of numerous radiatingspecies make assignments difficult these authors also believe that they haveobserved NH, bands in the infrared spectrum. There was, however, aR. D. Verma, J. Chem. Phys., 1960, 32, 738.31 R.P. Iczkowski and J. L. Magrave, J. Chem. Phys., 1959,30,403; 1960,83, 1261.3a J. T. Vanderslice, E. A. Mason, W. G. Maisch, and E. R. Lippincott, J. MoE.38 R. J . Fallon, J. T. Vanderslice, and E. A. Mason, J . Chem. Phys., 1960, 32, 1453.84 R. J. Fallon, J. T. Vanderslice, and E. A. Mason, J . Chem. Phys., 1960, 32, 698.*5 J . T. Vanderslice, E. A. Mason, W. G. Maisch, and E. R. Lippincott, J . Chem.86 I. Tobias, R. J. Fallon, and J. T. Vanderslice, J. Chew. Phys., 1960, 33, 1638.G. Herzberg and J. Shoosmith, Canad. J . Phys., 1956, 84, 523.88 A. Padgett and M. Krauss, J. Chem. Phys., 1960, 32, 189.K. N. Tanner and R. L. Kiflg, Nature, 1958, 181, 963.*O R. C. Lord and C. H. Sederholm, Spectrochim. Acta, 1959, 15, 605.Spectroscopy, 1959, 3, 17.Phys., 1960, 33, 61446 GENERAL AND PHYSICAL CHEMISTRY.disappointing lack of similarity between the ammonia and the hydrazineflame spectra.For the water molecule a new and thorough vibrational analysis hasbeen reported,O including first- and second-order anharmonicity constantsand many resonance interactions.The bending vibration of HDO has beenana1ysedF2 the vibration frequencies of D2lsO are reported,& and there havebeen very extensive measurements of the far infrared spectrum of water.44The more symmetrical hydrides have been studied even more extensivelyin the infrared region. The ammonia spectrum has been reported andanalysed in remarkable detail, both in the region of the stretching vibrationsq5and around the longcr-wavelength deformation vibrations ; 46947 ammoniabecomes one of the first molecules for which a Coriolis constant has beenaccurately determined relating to a non-degenerate pair of vibration^.^^For phosphine the bending vibrations have been studied and analysed insimilar and " K type doubling " has been observed for the first timein the K = 4 f- 3 and K = 2 + 3 sub-band lines.Several infraredbands of methane and its deutero-derivatives have been studied 49p50 andanaly~ed,P~~~l and similarly for ethane; 52 in most cases it is the very highresolving power ( 0 . 1 4 . 2 cm.-l) combined with a rather sophisticatedrotational analysis that has led to new and interesting results. There havebeen two careful discussions of the equilibrium bond length re in methane:the values deduced are 1.085, k in the two cases-a somewhat disappointing lack of agreement.The electronic spectra of the 15-valency-electron triatomic moleculesNCO 55 and NNO+ 56 have been recently reported and analysed.They areisoelectronic with the previously known C02+ molecule,G and all threeresemble the parent molecules CO, and N,O in their geometry, showing thatthe missing electron (which comes from a xg molecular orbital in the 211ground state) is essentially non-bonding in character. The 16-electronFCN molecule, isoelectronic with CO, and N20, has recently been preparedfor the first time, and its infrared 57 and microwave 58 spectra reported.and 1.091 & 0.002 k4 1 G. A. Khachkurazov, Optics and Spectroscopy, 1959, 6, 294.4* N.M. Gailar and F. P. Dickey, J . Mol. Spectroscopy, 1960, 4, 1.48 S. Pinchas, M. Halmann, and B. P. Stoicheff, J . Chem. Phys., 1959, 51, 1692.44 N. G. Yaroslavsky, Optics and Spectroscopy, 1959, 7, 380.45 W. S. Benedict, E. K. Plyler, and E. D. Tidwell, J . Chem. Phys., 1960, 32, 32.40 J. S. Garing, H. H. Nielsen, and K. N. Rao, J . Mol. Spectrosco$y, 1959, 3, 496.47 H. M. Mould, W. C. Price, and G. R. Wilkinson, Specfroclaim. Ada, 1959,15, 313.48 J. M. Hoffman, H. K. Nielsen, and K. N. Rao, 2. Electrochem., 1960, 84, 606;J . Chem. Phys., 1960, 32, 1597.4s H. C. Allen and E. K. Plyler, J . Aes. Nut. Bur. Stand., 1959, 63, A , 145.50 E. K. Plyler, E. D. Tidwell, and L. R. Blaine, J . Res. Nut. Bur. Stand., 1960,64, A ,201 ; D.H. Rank, D. P. Eastman, G. Skorinko, and T. A. Wiggins, J . Mol. S#ectroscoPy,1960, 5, 78; L. H. Jones, J . Mol. Spectroscopy, 1960, 4, 84.61 K. T. Hecht, J . Mol. Spectroscopy, 1960, 5, 355, 390.s* H. C. Allen and E. K. Plyler, J . Chem. Phys., 1959, 31, 1062.sa L. S. Bartell. K. Kuchitsu, and R. J. de Neui, J . Chem. Phys.. 1960, 32, 1254.s4 D. P. Stevenson and J. A. Ibers, J . Chem. Phys., 1960, 33, 762.65 R. N. Dixon, Phil. Trans., 1960, A , 252, 165.s6 J. H. Callomon, Proc. Chem. Soc., 1959, 313.67 R. E. Dodd and R. Little, Spactrochim. Acla, 1966, 16, 1.083.68 J. Sheridan, J. K. Tyler, E. E. Aynsley, R. E. Dodd, and R. Lifkle> Nature,1960, 185, 96MILLS : SPECTROSCOPY AND MOLECULAR STRUCTURE. 47The exceptionally short CF bond of 1.26& and the corresponding valueof 1.28A in fluoroacetylene reported in a recent microwave arevariously attributed to hyperconjugation or to rehybridisation and electro-negativity eff ects.60 The infrared spectrum of HB0,-again isoelectronicwith carbon dioxide-has also been observed.61 New infrared work oncarbon disulphide 62 and new vaccum-ultraviolet studies on CO,, COS,CS,, and N,O 63 are reported.Among the 17-valency-electron nonlinearmolecules the electronic spectrum of ONF 64 (no rotational analysis) andthe infrared spectrum of UNCl 65 have been observed.Overend has con-sidered, in a simple theoretical treatment, the cause of negative a rotationalconstants observed in the bending vibrations of hydrogen cyanide andacetylene .67Two novel methods of observing vapour-phase spectra have been de-scribed recently.The first is the study of magnetic rotation spectra,reported for IC1 and IBr 68 and for NO.69 These are observed by applyinga magnetic field to the absorbing gas in the direction of the beam of light,and then observing the spectrum of the gas contained between crossedpolarising elements: if either of the energy levels involved shows an appre-ciable Zeeman splitting a magnetic rotation spectrum will result (it isessentially a Faraday effect observed for the gas). Applications to structureanalysis and the measurement of dissociation limits are discussed. Thesecond is the study of infrared emission spectra excited by means of a radio-frequency discharge.Price and his co-workers 70 have described suchspectra, observed for a number of diatomic and small polyatomic molecules,and Eaton 71 has used the technique in a study of line intensities (discussedfurther below).Rotational analyses are naturally lesscommon for the larger molecules, and particularly for asymmetric tops,although extensive tables of energy levels for slightly asymmetric top mole-cules have appeared this year.72 However, comprehensive microwave studiesand detailed structural analyses are being reported on ever larger and lesssymmetrical molecules, which ten years ago would have frightened away thebest spectroscopist, and even rotational analyses of vibrational and electronicRank and his co-workers are still studying HCN.66Larger +olyafomic molecules.sg J.K. Tyler and J. Sheridan, Proc. Chem. Soc., 1960, 119.6o H. A. Bent, J. Chem. Phys., 1960, 32, 1582; 1960, 33, 304.D. White, D. E. Mann, P. N. Walsh, and A. Sommer, J. Chem. Phys., 1960, 32,62 A. H. Guenther, J . Chem. Phys., 1959, 31, 1095.Y. Tanaka, A. S. Jursa, and F. J. Le Blanc, J. Chem. Phys., 1959, 32, 1199,1025; N. Damany-Astoin, L. Samson, and M. C. Bonnelle, Compt. rend., 1960,250,1824.64 H. S. Johnston and H. J. Bertin, J. Mol. Spectroscopy, 1969, 3, 683.85 L. Landau and W. H. Fletcher, J. Mol. Spectroscopy, 1960, 4, 276.66 D. H. Rank, G. Skorinko, D. P. Eastman, and T. A. Wiggins, J. U p . Soc. Amer.,67 J . Overend, Trans. Faraday SOC., 1960, 56, 310.W. H. Eberhardt, W. Cheng, and H. Renner, J.Mot. Spectroscopy, 1959, 3, 664,69 G. A. Mann and C. D. Hause, J. Chem. Phys., 1960, 33, 1117.70 H. M. Mould, W. C. Price, and G. R. Wilkinson, Spectrochim. Acta, 1960, 16, 4’79.D. R. Eaton, Canad. J. Phys., 1960, 39, 390.72 S. C. Wait and M. P. Barnett, J. Mol. Spectroscopy, 1960, 4, 93; N. Januzzi andS. P. S. Porto, ibid., 1960, 4, 459; J . A. Norris and V. W. Laurie, J. Chem. Phys., 1960.32, 1591.488.1960, 50, 42148 GENERAL AND PHYSICAL CHEMISTRY.spectra are progressing. The vibrational spectra themselves are also ofinterest, particularly in relation to force-constant treatments discussedbelow. Broderson has developed an interesting theory of vibrational shiftsdue to isotopes,73 based on his complete isotope rule, in which frequencyshifts are divided into direct mass effects on the vibrational frequencies,plus interaction effects between the co-ordinates.BUCKINGHAM : ELECTRICAL AND MAGNETIC PROPERTIES OF MOLECULES’ 67Nuclear Quadrupole Coupling.-Nuclear quadrupole coupling constantse2qQ lead to information about the electric field gradient - eq at the nucleus,and hence about the electronic structure of the molecule.Unfortunately,the nuclear quadrupole moments eQ are not accurately known because ofthe difficulty of evaluating the shielding, or anti-shielding, effects of theinner electron shells. For the deuteron this difficulty does not exist, andBersohn 7 has used the known value of Q to determine field-gradients atdeuterons (and hence approximately at protons) in a number of simplemolecules.The values of q obtained provide very sensitive tests of wave-mechanical models for the molecules, and particularly check the accuracy ofelectronic wave functions in the vicinity of the protons [see eqn. (3)J. Theasymmetry in the field-gradient tensor qij, viz., q = (qx2 - qvv)/qzz, can alsobe used as a test of approximate wave functions for asymmetric molecules.7The subject has been well reviewed recently,193 and the only aspect of itto be reported here is the interesting one of the alkali-halide vapours. Theionic nature of these molecules should enable the field-gradients to beaccurately computed, but the electron antishielding leads to serious com-plications. If an isolated ion experiences an electric field-gradient E’, thenthe electron cloud of the ion leads to an additional gradient yoE’ at thenucleus, where yo is the anti-shielding factor and can be of either sign andas large as 100 (see Table I1 in a paper by Bersohn lg4), but only veryapproximate values are known.After allowances for antishielding in ionicmodels have been made, it is found lg5 that the observed coupling constantsat the metal nuclei can be approximately calculated, but those at the halidenuclei are much smaller than the computed values, and can change con-siderably with the vibrational quantum number (e.g., the chlorine-35coupling constant in potassium chloride changes by a factor of ten as vchanges from 0 to 3 lg6). The position is not improved by considering theinduced dipole and higher moments of the ions,195J97 and it has been con-cluded that covalency must be i n ~ o l v e d .~ ~ ~ J ~ ~ However, it may be possibleto retain the ionic model, which is known to be satisfactory in some otherrespects, by introducing another form of shielding constant, arising from thesquare of the electric field E acting on the isolated ion; the gradient at thenucleus of the ion then becomes(11) - e q = (I +yo)E‘+CE2 . . . . .where yo and < are characteristic properties of each ion, and are positive forthe alkalis (except yo for lithium) and for the halides. Hence - q for thepositive ions (for which E’ = 249, and E2 = e2//-p) is comprised of twopositive terms, while for the halides (E’ = - 2 4 9 , E2 = e2/1A) the two193 M. H. Cohen and F.Reif, (‘ Solid State Physics,” Vol. 5, Academic Press, NewYork, 1957, p. 321; T. P. Das and E. L. Hahn, “ Nuclear Quadrupole ResonanceSpectroscopy,’’ Academic Press, New York, 1958; W. J. Orville-Thomas, Quart. Rev.,1957, 11, 162.lg4 R. Bersohn, J . Chem. Phys., 1958, 29, 326.195 T. P. Das and M. Karplus, J . Chem. Phys., 1959, 30, 848.196 C. A. Lee, B. P. Fabricand, R. 0. Carlson, and I. I. Rabi, Phys. Rev., 1953, 91,187 G. Burns, Phys. Rev., 1959. 115, 357.l9* A. G. Makhanek, Optics and Spectroscopy, 1960, 9, 214.139568 GENERAL AND PHYSICAL CHEMISTRY.contributions oppose one another. If they are approximately equal, theresonant frequencies for chlorine, bromine, and iodine nuclei will all be verylow (as found), but the alkali nuclei will not experience this ‘‘ cancellationeffect.” This model, with just two adjustable constants (’yo and <) per ion,can approximately describe the observed coupling constants and theirdependence on the vibrational and rotational quantum numbers. Theconstant < may itself be an observable, for the field-gradients induced in acubic crystal by a strong uniform field E would be proportional to TE2, butunfortunately, the resulting coupling constants would normally be verysmall (see p.352 of the article by Cohen and Reif lg3). The coupling con-stants of nuclei that are in unsymmetrical positions within their moleculesor crystals should have a first-order dependence on E ; presumably therewill be ajrst-order Stark splitting of the pure quadrupole resonance lines incrystals of deuterium, iodine, etc., arising from the distortion of the electronclouds by the field.A.D. B.6. ELECTRON SPIN RESONANCENUMEROUS general reviews have appeared 1-4 since the last report.s Besidesgiving overall coverage of the main publications for the year in question,McConnell emphasises theoretical implications of results for aromaticradicals and radical-ions : Wertz dwells in particular upon transition-metalions in crystals and upon apparatus and techniques; Fraenkel and Segal3give a full account of work on organic radicals; whilst Berhson’s overlyingconcern 4 is with more theoretical aspects, especially the physical meaningof the parameters of spin Hamiltonians obtained from experiments, andrelaxation and exchange phenomena.Here, chemical aspects of recent work will be stressed, and advances inexperimental technique , quan t um-me ch anical computations, solid-state low-noise amplifiers, and antiferromagnetism will not be considered.For thosewishing to construct apparatus, attention is drawn to a helpful account byIngram.6Ions of the Transition-metal, Rare-earth, and Actinide Series in SingleCrystals.-The book by Low and review by Ortons give comprehensivecoverage to 1959. In addition Low discusses theoretical implications as doCarrington and Long~et-Higgins.~ The books by Orgel lo and especiallyby Griffithll are also relevant, as are several papers in a Faraday Society1 H. M. McConnell, Ann. Rev. Phys. Chem., 1957, 8, 105.2 J.E. Wertz, Ann. Rev. Phys. Chem., 1958, 9, 93. * G. K. Fraenkel and B. Segal, Ann. Rev. Phys. Chew., 1959, 10, 435.4 R. Bersohn, Ann. Rev. Phys. Chem., 1960, 11, 369.ti Ann. Reports, 19~5,7, 54, 9.6 D. J. E. Ingram,worth, London, 1958.7 W. Low, “ Paramagnetic Resonance in Solids,” Academic Press, London, 1960.8 J. W. Orton, Reports Progr. Phys., 1959, 22, 204.s A. Carrington and H. C. Longuet-Higgins, Quart. Rev., 1960, 14, 427.10 L. E. Orgel, “ An Introduction to Transition Metal Chemistry,” Methuen, London,11 J. S. Griffith, “ Ions of the Transition Elements,” Cambridge University Press,Free Radicals as Studied by Electron Spin Resonance,” Butter-1960.1961SYMONS : ELECTRON SPIN RESONANCE. 69Discussion.12 Recent work has centred largely on transition-metal ions asdilute impurities in host crystals such as the alkali and alkaline-earthhalides,U-lG and oxides such as those of rnagnesi~m,~~~~* aluminium,ls andtitanium.20 Spectra of fluorides are particularly informative becausehyperfine structure is often further split by the fluorine-19 nucleus to give‘‘ superhyperfine ” structure which can be interpreted directly in terms ofcovalent bonding.Low and his co-workers have studied calcium fluoridecontaining a range of paramagnetic ions because an inversion of levels isexpected for cubic symmetry compared with the more usual octahedralsymmetry. However, strong axial distortions were found, and attention isnow being given to strontium chloride because the larger ions should accom-modate impurity ions with less distortion.16Results for Co2+ in calcium fluoride, cadmium fluoride, and cadmiumtelluride can be interpreted satisfactorily by using the value 4,200 cm.-1 forlODq, estimated from the optical spectrum of Co2+ in cadmium fluoride.13Helmholtz 21*22 has analysed the resonance spectrum of FeFG3- in K,NaGaF,,and a re-examination l5 of the “ superhyperfine ” structure from Mn2+ inzinc fluoride has led to a modification of Tinkham’s analysi~.~3 The newresults agree well with nuclear resonance data for manganous fluoride.The tetrahedral oxyions Mn042-, Mn043-, and Fe042- have been studied,=and a detailed theoretical interpretation includes an account of weak satellitelines in the spectrum of Mn0,2- from which a value of the quadrupolemoment of manganese has been derived.25 It has been shown that theunpaired electrons in these ions are in a doubly degenerate level rather than atriplet as originally suggested by Wolfsberg and Helmholz.26 The resultsof a study of vanadium(1v) in titanium dioxide 2o are relevant to this workalthough there are six neighbouring oxygen atoms: “ forbidden ” Am = 1or 2 transitions are also clearly observed in this and other spectra.Wertz and his co-workers 27 have explained interesting spectra fromNi2+ and Co+ in magnesium oxide in terms of a double quantum transitionwhich is observed with a high level of microwave power as a very narrowband superimposed upon the ‘ I normal ” broad band.This band is sharpbecause the transition is not subject to anisotropic zero-field splittings, and12 Discuss.Faradar SOL, 1958, 26.13 T. P. P. Hall and W. Hayes, J . Chem. Phys., 1960, 32, 1871.14 W. Low, PYOC. Phys. SOC., 1960, 76, 307.15 A. M. Clogston, J. P. Gordon, V. Jaccarino, M. Peter, and L. R. Walker, Phys.18 W. Low and U. Rosenberger, Phys. Rev., 1959, 116, 621.17 J. Wertz, P. Auzins, J. H. E. Griffiths, and J. W. Orton, Discuss. Faraduy SOC.,18 W. Low and M. Weger, Phys. Rev., 1960, 118, 1130.1s J. Lambe and C. Kikuchi, Phys. Rev., 1960, 118, 71.20 H. J. Gerritson and H. R. Lewis, Phys. Rev., 1960, 119, 1010.21 L. Helmholtz, J . Chem. Phys., 1959, 31, 172.23 A. V. Guzzo and L. Helmholtz, J . Chew. Phys., 1960, 32, 302.23 M. Tinkham, PYOC. Roy. SOC., 1956, A , 236, 649.24 A.Carrington, D. J. E. Ingram, K. A. K. Lott, D. S. Schonland, and M. C. R.25 D. S. Schonland, Proc. Roy. SOC., 1960, A , 254, 111.86 M. Wolfsberg and L. Helmholz, J . Chem. Phys., 1952, 20, 837.2’) J. W. Orton, P. Augins, and J. E. Wertz, Phys. Rev. Letters, 1960, 4, 128; Phys.Rev., 1960, 117, 1222.1958, 26, 66.Symons, Proc. Roy. SOC., 1960, A , 254, 101.Rev., 1960, 119, 169170 GENERAL AND PHYSICAL CHEMISTRY.hyperfine structure from nickel-61 in natural abundance could be detectedas a result. Another unusual result is the observation of " superhyperfine "structure from cadmium nuclei in the spectrum of Mn2+ in cadmium sul-phide 2 8 ~ 29 and cadmium telluride,29 which implies considerable delocalisationof the unpaired electrons.This result is reminiscent of the very important data derived from para-magnetic centres in semiconductors, especially by the application of doubleresonance method^.^^^^Colour Centres in Alkali Halide Crystals.--In contrast to electrons trappedat impurity centres in solids such as silicon, electron spin resonance studieshave established that electrons in anion vacancies in alkali halides arestrongly localised in the vacancy.The formation and chemical propertiesof electron-excess and electron-deficit centres in such crystals have beenbriefly reviewed,32 and an important article on the structure of F-centreshas appeared.= An F-centre is formed in sodium azide exposed to ultra-violet light at 90" K which gives rise to a remarkably well-resolved electronspin resonance spectrum of 19 equally spaced lines with a hyperfine splittingconstant of 9.1 gauss.% This result shows that interaction with the nucleiof the six sodium ions which define the vacancy is very much stronger thanwith any other nuclei, thus confirming the concept that the electron isstrongly localised.A major development in which electron spin resonance played an out-standing part has been the discovery that ions such as Hal,-, Hal3-, andHal?- are important electron-deficit centres.35 The situation is complicatedwhen two or more centres or vacancies interact, but becomes relativelysimple again when colloidal metal particles are formed, with well-definedoptical and electron resonance spectra.Such spectra have now beenstudied for colloidal metals in irradiated lithium hydride 36 and sodiumazide?' as well as alkali halides.When ions having an outer shell of d-electrons are present in dilutesolution in such crystals, the usual reaction on exposure to high-energyradiation t o give F , V , and related centres can be variously modified, theimpurity ion acting as a source or sink of electrons or both.Thus, simpledisproportionations can be effected, such as 2Ag+ Ag2+ + Ago, and ionsin previously unknown valency states have been formed and studied in detailby this techniq~e.~'.~* This type of reaction may prove to be of general usefor the preparation of unstable species by gain or loss of an electron.PRUE: IONS IN SOLUTION. 89at this stage, with the release of attached water molecules.In four papersfollowing an introductory one,134 Laidler and his co-workers discuss thethermodynamic functions for ionisation processes of organic acids and bases,making use of their own measurements of heats of neutralisation.Kinetic Measurements.-An increasing number of examples is beingfound where even in dilute solutions specific interactions between reactingions andlor activated complexes with oppositely charged ions in the solutionare more important than the long-range interactions. Indelli has con-tinued 1% his work on specific salt effects on rates of reaction between fairlysimple ions. Wah1136 finds that the rate of the electron-transfer reactionbetween ferro- and ferri-cyanide ions (both 1 0 + ~ ) in O*OlM-tetraphenyl-arsonium hydroxide is about ten times smaller than in O.O1M-potassiumhydroxide; a decrease of the potassium hydroxide concentration to 0.001 1~causes the rate to fall by a factor of 8.9.A change of anion has no effect.The hydrolysis of organic phosphate anions is markedly accelerated byadded cati~ns.l~~s 138 Ion-association effects in non-aqueous solutions areincreasingly emphasised by organic chemists. Such effects can cause anapparent reversal of the nucleophilic reactivity of the halide ions in acetonewhen tetrabutylammonium halides are replaced as reactants by lithiumhalides.la9 Winstein and his co-workers continue 140 to stress the im-portance of the distinction between ionisation and dissociation in mechan-istic discussions. Highly specific salt effects for the solvolysis and racemis-ation of alkyl sulphonates are reported la by Grunwald et al.Theory.-By accurate numerical integration of the Poisson-Boltzmannequation, Guggenheim 142 has calculated theoretical values of the activitycoefficients and thence osmotic coefficients for 2 : 2-electrolytes in diluteaqueous solution. The values are compared with experimental ones andwith those predicted by the theories of Bjerrum, Gronwall, and Mayer.Divergences from the last when Ka >0.1 may be due to the neglect ofterms of higher order than ( K U ) ~ in Mayer’s theory.In a subsequent paper:&Guggenheim points out that whereas the degree of dissociation accordingto Bjerrum depends on the choice of an association distance, it is possible todefine a related quantity which does not depend on this choice.Thisquantity, which he calls the degree of “ supersociation,” is the integral overall distances of the difference between the fraction of pairs of ions in aspecified position of propinquity, and the fraction there would be if the ionswere distributed throughout according to the potential which becomes134 K. J. Laidler, Trans. Faraday SOC., 1959, 55, 1725.135 A. Indelli and E. S. Amis, J . Amer. Chem. SOL, 1960, 82, 332; A. Indelli, G.136 A. C. Wahl, 2. Elektrochem., 1960, 64, 90.137 G. 0. Dudek and F. H. Westheimer, J . Amer. Chem. SOC., 1959, 81, 2641.138 J. L. Kurz and C. D. Gutsche, J . Amer. Chem. SOC., 1960, 82, 2175.139 S. Winstein, L. G. Savedoff, S. Smith, I.D. R. Stevens, and J. S. Gall, Tetrahedron140 S. Winstein, J. S. Gall, M. Hojo, and S. Smith, J . Amer. Chem. SOC., 1960, 82,141 E. F. J. Duynstee, E. Grunwald, and M. L. Kaplan, J . Amer. Chem. SOC., 1960,14% E. A. Guggenheim, Trans. Faraday SOC., 1960, 56, 1162.143 E. A. Guggenheim, Trans. Furuday Soc., 1960, 56, 1169.Nolan, and E. S. Amis, ibid., p. 3237.Letters, 1960, No. 9, p. 24.1010; S. Winstein, M. Hojo, and S. Smith, Tetrahedron Letters, 1960, No. 22, p. 12.82, 565490 GENERAL AND PHYSICAL CHEMISTRY.valid for that particular electrolyte in the limit of large separation of theions. It remains to be seen whether it will be possible to determine thisquantity experiment ally.Friedman continues his development of Mayer’s theory.The applic-ation to electrolyte mixtures leads to the conclusion that Bronsted’sprinciple of specific interaction is less accurate than has formerly been sup-posed. A second paper 145 develops a system of excess functions for electro-lyte solutions which are said to offer some advantages over other methods ofcomparing Mayer’s theory with experiment, of representing the propertiesof solutions of single or mixed electrolytes, and of making qualitative inter-pretations of the molecular basis of thermodynamic properties. Graphsare given showing the excess free energy, enthalpy, entropy, and volume forseveral aqueous single electrolytes up to 6M. The author points out thatconsideration of such excess curves does not confirm conclusions aboutinteractions drawn from qualitative discussions of trends in plots of activitycoefficients against concentration.In a series of four papers,146 Kelbg has derived expressions for the radialdistribution function and thence the osmotic coefficient of an electrolytesolution both for the Debye-Hiickel model and for a model with an addi-tional square-well attractive potential at close approach.The latter fitsthe results for tetra-alkylammonium salts well, but there remain two adjust-able parameters, viz., the ion-size parameter and one related to the depthof the potential well at close approach.A theoretical paper by Dejaklg7 continues a lengthy series on concen-trated solutions of strong electrolytes. A comprehensive review of theoreti-cal work, including Russian contributions, was published 148 in 1959.J.E. P.8. FAST REACTIONS IN SOLUTIONTHE publication of the papers given at an International Colloquium on fastreactions in solution1 shows the advances which have been made since asimilar previous meeting was held.2 In this report we cover some aspectsof fast processes in solution. Problems dealing specifically with energytransfer3 and with perturbations by high-energy radiation have not beendealt with. The rates of simple acid-base reactions were reviewed last year.4It is often possible to study a fast reaction in the steady state by usingcompetition between the chemical reaction and some other physical processof known rate. The rate constant can then be found in terms of the knownprocess, e.g., mass transfer in continuous flow, diffusion in polarography,144 H. L.Friedman, J . Chem. Phys., 1960, 32, 1132.145 H. L. Friedman, J . Chem. Phys., 1960, 32, 1351.146 G. Kelbg, 2. phys. Chem. (Leipzig), 1960, 214, 8, 26, 141, 153.147 C . Dejak, Ann. Chim. (Italy), 1960, 50, 956.148 H. Falkenhagen and G. Kelbg, “ Modern Aspects of Electrochemistry,” No. 2,ed. J. O’M. Bockris, Butterworths Scientific Publications, London, 1959, p. 1.1 2. EleRtrochem., 1960, 64.2 Discuss. Faraday Soc., 1954, 17.3 E.g., Discuss. Faraday Soc., 1959,27; Th. Forster, 2. Elektrochem., 1960, 64, 157;M. Burton and H. Dreeskamp, ibid., p. 165.4 R. P. Bell, Quart. Rev., 1959, 13, 169BEWICK AND FLEISCHMANN: FAST REACTIONS IN SOLUTION. 01heat loss in the thermal maximum method: ionic migration in Eigen’sstationary-field method, and competition with the nuclear spin transitionin the nuclear magnetic resonance technique. In enzyme systems the com-petitive process may be purely chemical.The substrate is present in excesswhile the enzyme is regenerated. It has been shown that lower boundsfor the bimolecular rate constants, E + S, can be obtained from the maxi-mum velocities and these approach diffusion control ’ in some cases.Considerable effort has been devoted to the development of very sensitivedetection methods (e-g., spectrophotometric coupled to systems with highextinction coefficients) which allow the use of very small concentrations. Inthis way the range of velocity constants accessible to any method can beextended.There has been great interest in recent years in the techniquesfor studying fast processes which have become known as relaxation methods.A feature of these experiments is that the equilibrium position of a chemicalreaction is rapidly perturbed by physical means.Flow Techniques.-Rapid mixing was first developed by Hartridge andRoughton using a flow system,8 which they applied to biochemical reactions.Roughton has reviewed flow techniques9 The low flow rates required bythe slower reactions produce inefficient mixing. The capacity flow method locovers this range and provides an extended region of steady concentrationsuitable for spectrophotometric measurements of transient species-ll Agreat economy in the volume of reactants is achieved by employing theflow technique merely for mixing, then using rapid recording of the non-steady state in the stopped fluid.12 The time-resolution of flow methods islimited to about sec.by inhomogeneous mixing and cavitation effectsat high flow rates; however, see ref. 13.Many ingenious recording techniques have been deve10ped.l~ Sensitivespectrophotometric methods can detect millimicromolar quantities inhzmoprotein reactions, allowing the measurement of second-order rateconstants up to los 1. mole-l sec.-l.13 Microphotospectrometric and micro-fluorometric methods have been developed with sensitivities of 10-20 molesof cytochrome or reduced pyridine nucleotide, allowing the measurement ofdiffusion-controlled reactions but using a time scale of seconds.14 Anothernew technique for detection is provided by the application of the Rankine-balance measurement of volume magnetic susceptibility to flow systems.155 R.P. Bell and J. C. Clunie, Proc. Roy. Suc., 1952, A , 212, 16.6 L. Peller and R. A. Alberty, J . Amer. Chem. SOC., 1959, 81, 5907.7 (a) L. Onsager, J . Chem. Phys., 1934,2,599; (b) P. Debye, Trans. Electrochem. SOC.,1942, 82, 265.8 H. Hartridge and F. J. W. Roughton, Proc. Roy. SOC., 1923, A, 104,376; F. J. W.Roughton, “ Technique of Organic Chemistry,” ed. Weissberger, Interscience, NewYork, 1953, Vol. 8, Ch. 10.9 F. J. W. Roughton, 2. Elektrochem., 1960, 64, 3.10 K. G. Denbigh. Trans. Faraday SOC., 1944, 40, 352; K. G. Denbigh and F. M.11 F. M. Page, Trans.Faraday SOC., 1953, 49, 635; Idem, Spectrochim. Acta, 1957,12 Q. H. Gibson, Discuss. Faraday SOC., 1954, 17, 137.1s B. Chance, 2. Elektrochem., 1960, 64, 8.14 B. Chance, R. Perry, L. Ackerman, and B. Thorell, Rev. Sci. Instr., 1959,30, 735;16 A. S. Brill, Ph.D. Diss. Pennsylvania, 1956, quoted in ref. 13.Page, Discuss. Faraday Soc., 1954, 17, 145.Suppl., 594.B. Chance and V. Legallais, ibid., p. 73292 GENERAL AND PHYSICAL CHEMISTRY.The complete visible and ultraviolet spectrum of transient species can nowbe recorded every sec.16Baldwin and Taube have combined the isotopic-dilution method with aflow system.17 The hydration numbers for the cations Fe3+, N3+, andNi2+, and an estimate of the half lives for the exchange of hydrated water,were obtained.Thermal measurement with continuous flow has beenapplied to the hydrolysis of chlorine.ls The most likely mechanism involvesreaction with water molecules rather than hydroxyl ions.Conductivity and pH measurements, in a stopped-flow system have beendeveloped and applied to the reactions : lQOH- + CO, HCOS-H+ + HCOS- H2CO3 Ha0 + CO,and to the hydrolysis of organometallic halides.20 Low temperatures canbe used to reduce the rate of fast reactions. A low-temperature (down to- 120" c) stopped-flow technique has been applied to the reactions of ethoxideion with ZJ4,6-trinitrotoluene and p-nitrobenzyl cyanide, and of acetic acidwith et hoxide-trinitrobenzene .21Biochemical reactions are still extensively studied by flow techniques.g.13The four stages in the reaction of haemoglobin with oxygen and carbonmonoxide, etc., are well characterised.The very large rate constant,7 x 107 1. mole-l secrl, for the haematin-globin reaction indicates a diffusion-controlled reaction 22 between the haem groups and the surface of the globinmolecule .=Radicals in flow systems have been studied by electron spin resonance.The oxidations of quinol,% ascorbic acid, and dihydroxyfumaric acid werereported.25In relaxation measurements ,physical methods are used to perturb the equilibrium position of a chemicalreaction e.g.,Relaxation Methods-Small perturbations.k',, k**ksi k,aA + B =+= AB AB'Chemical relaxation has been considered from the viewpoint of the thermo-dynamics of the steady ~ t a t e .~ ~ ~ ~ ~ The system can be kinetically specifiedas follows: 2 8 ~ 2 ~ if the perturbation is small the usual kinetic equations can16 G. V. Biinau, L. de Maeyer, and P. Matthies, 2. EZeRtrochem., 1960, 64, 14; W.17 H. W. Baldwin and H. Taube, J. Chem. Phys., 1960,33,206.18 A. Lifshitz and B. Perlmutter-Hayman, J . Phys. Chem., 1960, 84, 1663.19 J. A. Sirs, Trans. Faraday Soc., 1958, 54, 201, 207.20 R. H. Prince, 2. Elektrochem., 1960, 64, 13; Idem, Trans. Faraday Soc., 1958,21 c . R. Allen, A. J. W. Brook, and E. F. Caldin, Trans. Faraday SOC., 1960, 5.6, 788.22 R. A. Alberty and G. G. Hammes, J. Phys. Chem., 1958, 62, 154.2s Q. H. Gibson, A. R. Fanelli, and E. Antonini, 2. Elektrochem., 1960, 64. 4.24 B. Venkataraman and G.K. Fraenkel, J . Amer. Chem. Soc., 1955, 77, 2707.25 I. Yamazaki and H. S. Mason, Biophys. Res. Comnzn., 1959, 1, 336.26 J, Meixner, Kolloid. Z., 1953, 134, 3.27 J. G. Kirkwood and B. Crawford, J . Phys. Chem., 1952, 56, 1048.28 M. Eigen, Discuss. Faraday SOC., 1954, 17, 194.29 M. Eigen, Discuss. Faruday SOC., 1957, 24, 26.Niesel, D. Lubbers, and G. Thews, ibid., p. 15.84, 838; Idem, J., 1959, 1783BEWICK AND FLEISCHMANN: FAST REACTIONS I N SOLUTION. 93be linearised (ie., the contribution of the second-order step) and if xl, x2, x3are the deviations of the concentrations of A and B, AB, and AB' from theinitial values, xl'(t), x2'(t), x3'(i) are the corresponding forcing functions,which are all of the same form:and similarly for the other variables.The solution of a sequence of first-order equations has been considered frequently in chemical kinetics andmany special results are k n ~ w n . ~ ~ ~ ~ ~ s ~ ~ The problem also arises in relatedquestions such as the effect of time-dependent activation processes on thereaction 32 or in the conditions for a steady state.33 The formal similarity ofchemical relaxation to the normal vibration of molecules has been pointed0 ~ t . ~ ~ 9 ~ ~ ~ ~ If D denotes the differential operator and x and x' the columnvectors of the concentration variations and forcing functions, then(DI + A)x = AX'where A is the matrix of the rate constants.the basis can be changed so thatBy a similarity transformation(DI + B)y = By'where B is the diagonal matrix.The vector y gives the normal co-ordinatesof the system, and the invariant relaxation times & can be found from thesecular de t ennin an tIt is instructive also to consider the rate equations in operational form 35IA - XI1 = Oetc., wherevalue of xl.The time variations of the components are given bydenotes the Laplace transformation and xl0 is the initialIn the general case the right-hand side is a function of p .AA where A is the adjoint matrix, x is the vector of the forcing terms (the right-hand sides of the equations) and I A I is the determinant of the coefficients ofthe left-hand side. The reciprocals of the relaxation times are given 27 bythe poles of I A 1 = 0, which are the same for all the components. For thesimple system illustrated above one of the relaxation times is infinite.Thishas been attributed to the concentration balance 29 but it can be seen to bedue to the symmetry of the matrix which reflects the symmetry of the80 E.g., A. Rokowski, 2. phys. Chem., 1907, 57, 321; J. A. Christiansen, ibid., 1935,28, B, 303; 1936,33, B, 145; Idem, Acta Chem. Scawd., 1949,3,493; R. Lumry, Discuss.Faraday Soc., 1955, 20, 257.31 F. A. Matsen and J. L. Franklin, J . Amer. Chew. SOL, 1960, '92, 3337.82 B. J. Zwolinski and H. Eyring, J . Amer. Chem. Soc., 1947, 69, 2702.33 K. G. Denbigh, M. Hicks, and F. M. Page, Trans. Furaday Soc., 1948, 44, 479.34 M. Eigen, 2. Ebktrochem., 1960, 64, 115.35 H. M. Bateman, Proc. Camb. Phil. Soc., 1910, IS, 42394 GENERAL AND PHYSICAL CHEMISTRY.reaction scheme.The position of these roots must in general be deter-mined by this symmetry. The formal solution of the matrix equation hasalso been cast 36 into an interesting form which involves only a finite numberof matrix multiplications, apparently by using Sylvester's theorem or itsequivalent. The general solution of the forced problem could be obtainedby the same method. In enzyme reactions, a great excess of substratebeing used, one of the relaxation times becomes that of the stationary stateand this value has been measured 37 for the fumarase-catalysed hydration offumarat e to L-malat e.A variety of physical methods has been used to perturb chemicalequilibria. The dissociation of weak acids induced by high fields'" hasbeen f o l l ~ w e d , ~ , ~ ~ temperature jumps have been produced in conductingsystems by means of large and oscillating temperatures innon-aqueous systems by means of ultrasonic vibration^:^ while pressureperturbations alone apply to aqueous solutions.The forcing termshave had a limited number of forms : step functions,38~40*45~46 highly damped0scillations,3~ and continuous os~illations.~s~ Measurements have beenmade by following spectrophotometrically 39-41 the transient variations ofthe concentration of a single species in response to a step function, usuallyby coupling to a second equilibrium, or by measuring the response of aphysical parameter of the system as a whole (electrical cond~ctivity,~*3~,45s~~sound absorption 44> to a step function 38340*G~46 or to the forcing term.39~~~The experimental techniques have been re~iewed.~~,~' The measurementof dielectric absorption has also been suggested.aPressure- and temperature-jump methods have been found suitable fortimes > 10-5 sec.while the ultrasonic and field dissociation methods applyfor shorter times. It has usually been assumed that in the liquid phasethe relaxation time of the solvent structure is small compared to that of thesystem investigated. This is largely confirmed by the fact that some fastprocesses can be analysed in terms of a single relaxation time.49 Thedependence of the relaxation time on the nature of the perturbation is,26 atpresent, not accessible to measurement.The results for metal-complex formation,= protolytic equilibria,% androtational isomerism and molecular association have been reviewed.313 R.A. Alberty and G. G. Hammes, 2. Elektrochem., 1960, 64, 124.37 R. A. Alberty and G. G. Hammes, J. Amer. Chem. Soc., 1960, 82, 1564.a* M. Eigen and L. de Maeyer, 2. Elektrochem., 1955, 59, 986.as M. Eigen and J . Schoen, 2. Elektrochem., 1955, 59, 483.40 G. Czerlinski, H. Diebler, and M. Eigen, 2. phys. Chem., 1959, 19, 246.41 G. Czerlinski and M. Eigen, 2. Elektrochem., 1959, 63, 652; I d e m , Angew. Clzem.,42 H. Diebler and M. Eigen, 2. phys. Chem., 1959, 20, 299.43 J . H. Andreae, E. L. Heasell, and J. Lamb, Proc. Phys. Soc., 1956, B, 69, 625.44 M. Eigen, G. Kurtze, and K. Tamm, 2. Elektvochem., 1953, 57, 103.45 S. Ljunggren and 0.Lamm, Acta Chem. Scand., 1958, 12, 1834.46 H. Strehlow and M. Becker, 2. Elektrochem., 1959, 63, 457; H. Wendt and H.47 L. deMaeyer, 2. Elektrochem., 1960, 64, 65; K. Tamm, ibid., 1960, 64, 73.48 R. G. Pearson, Discuss. Faraduy Soc., 1954, 1'4, 187.49 R. 0. Davies and J. Lamb, Quart. Rev., 1957, 11, 134.50 J. Lamb, 2. Elektroclzem., 1960, 84, 135.61 W. Maier, 2. Elektrochem., 1960, 64, 132.1958, 70, 629.Strehlow, ibid., 1960, 64, 131BEWICK AND FLEISCHMANN FAST REACTIONS IN SOLUTION. 95In the case of weak association 28,44 in 2 : 2-vdent electrolytes two discretesteps are observed and another due to the ionic atmosphere is noted. One ofthese steps is independent of the nature of the ions and has been attributedto the removal of a first solvent layer:MliO<H *<" A2- MS+O/H AS- MS+A2-H H \HThe second step at lower frequencies depends on the nature of the cationonly since similar rate constants are observed with strong complexingagents 42 (e t h ylenediamine t et ra- ace t ic acid, ph t halein-complexone) .AnSNl mechanism has been differences being confined to thedissociation steps, some of which can be measured also by exchangemeth0ds.6~ The reaction rates also show a parallelismM to those forH27O exchange as measured by nuclear magnetic resonance.% It hasbeen found that Be2+ also shows further hydrolysis equilibria at lowerfrequencies.The recombination of hydrogen and hydroxyl ions38 and the rates ofseveral acid-base reactions coupled by this equilibrium 38939954 have beenmeasured: H+ + CH,*CO,- =$= CH3*C02H;NH,+ + OH- C NH,-OH; Hf + F- G+ HF.It is found that the bimolecular recombination step is frequently diffusioncontrolled, and it has been suggestedM that the subsequent movement ofthe proton and re-orientation of the water molecules55 in an extendedwater structure is still faster.Proton transfer has also been studied be-tween imidazole and water; imidazole and Chlorophenol Red as a protondonor-acceptor system; 56 A.D.P. and Chlorophenol Red and Phenol Redand between A.D.P. and Chlorophenol Red in the presence of Mg2+ andCa2+ Most of the rate constants have been obtained from the con-centration dependence; some of the steps are again diffusion controlled.Ultrasonic measurements have been used in the investigation of rotationalisomerism in solution.58 Recent measurements 59 with ethyl formate haveshown that an increase in the dielectric constant of the solvent increases therelative stability of the isomer of higher dipole moment.Two relaxationregions have been found for solutions of acetic acid, one of which has beenattributed to the monomer-dimes reaction.m The association of benzoicacid in carbon tetrachloride and in toluene has also been measured.61 OneH+ + SOZ- =+ HSO,-;H+ + HS- + H,S;52 C. 1%. Cook and F. A. Long, J . Amer. Chem. SOC., 1958, 80, 33.63 R. E. Connick and R. E. Poulson, J . CAem. Phys,, 1959, 30, 759.64 M. Eigen, 2. phys. Chem., 1954, 1, 176; M. Eigen and K. Kustin, J . Amer. Chew.55 M. Eigen and L. de Maeyer, PYOC.ROY. SOC., 1958, A , 247, 505.56 M. Eigen, G. G. Hammes, and K. Kustin, J . Amer. Chem. Soc., 1960, 82, 3482.57 M. Eigen and G. G. Hammes, J . Amer. Chem. Soc., 1960, 82, 5951.58 M. S. de Groot and J. Lamb, Proc. Roy. Soc., 1957, A , 242, 36; J. H. Chen andA. A. Petrauskas, J . Chein. Phys., 1959, 30, 304; E. L. Heasell and J. Lamb, Proc. Boy.SOC., 1956, A , 237, 233.59 D. N. Hall and J. Lamb, Trans. Faraday SOC., 1959, 55, $84.80 J. E. Piercy and J. Lamb, Trans. Faraday Soc., 1956,52,930; see also D. Tabuchi,61 W. Maier, L. Baruchi, B. Dischler, P. Manogg, and H. Riesenberg, 2. phys. Chem.,SOC., 1960, 82, 5952.2. Ebktrochem., 1960, 64, 141.1960, 26, 27; W. Maier, K. H. Krebs, and J. Stange, ibid., 1960, 23, 21096 GENERAL AND PHYSICAL CHEMISTRY.relaxation region is found in carbon tetrachloride; the value of the recom-bination rate constant is close to that for diffusion control. Pressure-impulse methods have also been used45146 to measure the kinetics of form-ation of the binuclear complex FeOFe4+, and the reaction of water withcarbon dioxide.The photostationary state of acontinuously perturbed equilibrium has been investigated frequently.62163Additional kinetic information can be obtained by combining the reactionwith a second scavenging process.64, 65 A considerable advance results fromthe use of intermittent illumination to change the reaction rates or pro-d u c t ~ , ~ ~ - ~ ~ a technique closely related to flash photolysis in which thesystem is perturbed by light and the relaxation follovved.68~ 69 The dark back-reaction succeeding illumination is followed and, for example, in the thionine-ferrous ion reaction, the high extinction coefficient permits the measurementof relatively large rate constants even though a time scale of several secondsis used.70Recent technical improvements include considerable development ofshorter-duration and higher-energy flash larnps,?l and repetitive flashte~hniques.7~ Increase in the sensitivity permits the detection of 0.1%change of concentration in s ~ c .~ ~ A conductimetric detection methodhas also been des~ribed.~~ The application of flash photolysis to fastreactions in solution has been discussed.71Interest in the recombination of iodine atoms in a variety of inert sol-vents has continued74 (cf.62, 64, 67). Agreement between the variousmethods is good and the rates have been shown to be consistent with diffusioncontrol.67 However, a recent investigation of the complex formation be-tween iodine and benzene75 yielded a rate for the recombination via thecomplex eighteen times greater than that for free iodine atoms in carbontetrachloride. The apparent contradiction has not been explained. Fourprocesses have been found in the primary steps of photo~ynthesis,~~ of whichthree are normally observed.?’ The fastest is due to the excitation of chloro-phyll a 7 7 linked to the substrate, and two slower processes 77966 are due tothe reactions involved in the splitting of water and a redox stage a t theLarge perturbations.-Flash photolysis.62 E.Rabinowitch and W. C. Wood, Trans. Faraduy Soc., 1936, 32, 547.63 E. Rabinowitch, J . Chem. Phys., 1940, 8, 551.64 F. W. Lampe and R. N. Noyes, J . A r e r . Chem. Sac., 1954,76, 2140.65 H. W. Melville and G. M. Burnett,66 R. Emerson and W. Arnold, J . Gan. Physiol., 1932, 15, 391; 1932, 16, 191.67 H. Rosman and R. N. Noyes, J . Amer. Chem. Sac., 1958, 80, 2410.68 G. Porter, Pvoc. Roy. SOL, 1950, A , 200, 284.60 G. Porter, Proc. Chern. Sac., 1959, 291.70 J. Schlag, 2. phys. Chem., 1959, 20, 53.7 1 G. Porter, 2. EZeRtrochem., 1960, 64, 59.72 H. T. Witt, R. Moraw, and A. Muller, 2. phys. Chem., 1959, 20, 193.73 H. Ruppel and H. T. Witt, 2. phys. Chem., 1958, 15, 321.74 S. Aditsa and J. E. Willard, J .Amer. Chem. SOC., 1957, 79, 2680; R. L. Strongand J. E. Willard, 7. Amer, Chem. Sac., 1957, 79, 2098; R. Marshall and N. Davidson,J . Chem. Phys., 1953, 21, 2086.75 S. J. Rand and R. L. Strong, J . Amer. Chem. Sac., 1960, 82, 5.76 H. T. Witt, R. Moraw, A. Miiller, B. Rumberg, and G. Zieger, 2. phys. Chem.,1960, 23, 133.77 H. T. Witt and R. Moraw, 2. phys. Chem., 1959, 20, 253, 283.Techniques Org. Chem.,” 1953, ed. Weiss-berger, Interscience, New York, Vol. 8, ch. 3BEWICK AND FLEISCHMANN: FAST REACTIONS IN SOLUTION. 97end of the primary process.’’ For comprehensive references on photo-synthetic processes see ref. 78.There will generally be different equilibrium positions for a system inthe ground state and the excited state. If the equilibrium of the excitedstate is achieved before deactivation takes place, then the ground-stateconcentration will be perturbed and its relaxation may be observed.Arom-atic hydroxy-compounds are usually much stronger acids in the excited stateand have been investigated by this technique 79ROH RO- + H+* *hv+ t lhv’ROH -+ RO-+ H+Fluorescence measzcrements. The usual application of the reactionscheme already illustrated has been in the measurement of associations0and proton transfer in excited systems. The ionisation in the excitedstate takes place in competition with fluorescence and radiationless transi-tion of the undissociated excited molecule to the ground state. The rateconstants can be obtained by measuring the relative intensities of fluor-escence of the two excited species, for example as a function of pH.83 Protontransfer to the p-naphthoxide ion s2 and from p-naphthol to a number ofbases has been m e a ~ u r e d .~ * ~ ~ The recombination rates are again close tothe diffusion limit. The basicity of acridine is greater in the excited thanin the ground state 8 5 ~ ~ and by suitably buffering the solution with ammoniait is possible to measure both the reactions.* *Acridine,H,O Acridine H+ + OH-Acridine + NH,+ __t Acridine H+ + NH,* *It has been reported that hydrated cations can also act as proton donors.Nzlclear magnetic resonance. The mean lifetime in a given state, 7, of anucleus in an exchange reaction is related to the separation of the spin-spindoublet corresponding to the two chemical environments. A fast exchangerate, small value of T, produces instead of the doublet, a broad singlet witha half-width related to T.The effect can be represented:Increasing rate of exchange.Sharp multiplet __f Line broadening and overlap Broad singlet~~78 Discuss.Faraday Soc., 1959, 27, 144, 149, 161.79 K. Breitschwerdt, Th. Forster, and A. Weller, Naturwiss., 1966, 43, 443; K.80 Th. Forster and K. Kasper, 2. phys. Chem., 1954, 1, 275; Idem, 2. Ebklrochem.,Breitschwerdt and A. Weller, 2. phys. Chem., 1969, 20, 353.1955, 59, 976.Th. Forster, 2. Elektrochem., 1950, 54, 42, 531.A. Weller, 2. phys. Chem., 1958, 17, 224.88 A. Weller, 2. phys. Chem., 1957, 13, 335; 1958, 15, 438.84 A. Weller, 2. Elektrochem., 1954, 58, 849.A.Weller, 2. Elektrochem., 1960, 64, 55.*6 A. Weller, 2. Elektrochem., 1957, 61, 956.REP.-VOL. LVII 98 GENERAL AND PHYSICAL CHEMISTRY.These effects are the result of competition between the exchange rate andthe nuclear transition rate. The origin and development of the rathercomplex theory relating rate constants to the observed spectra can befollowed in ref. 87. A unique advantage of nuclear magnetic resonancelies in its applicability to the study 88 of symmetrical processes, e.g.,NH,+ + NH, e, NH, + NH,+Several proton-transfer processes in solutions of ammonium salts havebeen studied 89*90 over a wide range of pH and concentration. The rate ofreaction between ammonia molecules and the hydrated proton is consistentwith diffusion control and a hydrated proton of size, H,O,+, provided thatmolecular rotation is fast.g0 The three methylamines have been studiedlikewise.g1 The protolysis and hydrolysis of N-methylacetamide andN-methylformamide have been investigated g2, 93 and activation energiesobtained.g3 Proton exchange as a function of pH has been measured inethanol,% aqueous hydrogen peroxide,95 and aqueous methanol.w A recentreview on nuclear magnetic resonance and molecular structure includes thetopics molecular association, keto-enol tautomerism, hindered rotation, andrate of inversion of hydrogen about the pyramidal nitrogen of substitutede t hyleneimines .97The effect of paramagnetic ions in solution upon the line shape of thenuclear magnetic resonance signal from solvent protons, can be used toobtain the exchange rate between co-ordinated molecules and the bulk~ o l v e n t .~ * ~ ~ ~ A recent analysis gg derives an expression for the line widthfrom a proton undergoing exchange between paramagnetic and diamagneticenvironments in terns of the exchange rate constant and the relaxation87 H. S. Gutowsky, D. W. McColl, and C. P. Slichter, J . Chem. Phys., 1953, 21, 279;H. S. Gutowsky and A. Saika, ibid., 1953, 21, 1688; H. S. Gutowsky and H. S. Holm,ibid., 1956, 25, 1228; E. Grunwald, A. Loewenstein, and S. Meiboom, ibid., 1957, 27,630; A. Loewenstein and S. Meiboom, ibid., 1957, 27, 1067; H. M. McConnell, ibid..1958, 28, 430; J. I. Kaplan, ibid., 1958, 28, 278; R. A. Sack, Mol. Phys., 1958, 1, 163;L.H. Piette and W. A. Anderson, J . Chem. Phys., 1959, 30, 899; H. Eyring, T. Ree,D. M. Grant, and R. C. Hirst, 2. EEektrochem., 1960, 64, 146.88 R. A. Ogg, J . Chem. Phys., 1954, 22, 660; Idem, Discuss. Faraday SOC., 1954,17,215; R. A. Ogg and J. D. Ray, J . Chem. Phys., 1957,26, 1339, 1340.89 S. Meiboom, A. Loewenstein, and S. Alexander, J . Chem. Phys., 1958, 29, 969.90 M. T. Emerson, E. Grunwald, and R. A. Krornhout, J . Chem. Phys., 1960,83, 547.91 E. Grunwald, A. Loewenstein, and S. Meiboom, J . Chem. Phys., 1956, 25, 382;1957, 27, 630; A. Loewenstein and S. Meiboom, ibid., 1957, 27, 1067; E. Grunwald,P. J. Karabatsos, R. A. Kromhout, and E. L. Purlee, ibid., 1960, 33, 556.98 A. Berger, A. Loewenstein, and S. Meiboom, J . Amer. Chem.SOL, 1959, 81, 62;M. Takeda and E. 0. Stejskal, ibid., 1960, 82, 25; G. Fraenkel and C. Franconi, ibid.,p. 4478.@a A. Saika, J. Amev. Chem. Soc., 1960, 82, 3540.94 J. T. Arnold, Phys. Rev., 1956, 102, 136.95 M. Anbar, A. Loewenstein, and S. Meiboom, J . Amer. Chem. SOC., 1958, 80,96 2. Luz, D. Gill, and S. Meiboom, J . Chem. Phys., 1959, 30, 1640.97 A. T. Bottini and J. D. Roberts, J . Amer. Chem. SOC., 1956, 78, 6126; 1958, 80,98 S. Broesma, J. Chem. Phys., 1956, 24, 153, 659; 1967, 27, 484; A. Bernheim,99 R. G. Pearson, J. Palmer, M. M. Anderson, and A. L. Allred, 2. EZektvochem., 1960,2630.6203.T. H. Brown, H. S . Gutowsky, and D. E. Woesmer, ibid., 1959,30, 950.04, 110BEWICK AND FLEISCHMANN: FAST REACTIONS IN SOLUTION, 99rates in co-ordinated and unco-ordinated molecules.The line width showsa linear dependence on concentration, and tests are developed for decidingwhether the exchange or the relaxation is rate-determining. Ammonia andethylenediamine complexes of chromium(II1) were studied at several pHvalues. In strongly alkaline solution the total line broadening was attri-buted to the base-catalysed proton-exchange for which rate constants wereobtained. These agreed with values obtained at low pH by using con-ventional isotope exchange.1o0 Measurements were made with severalparamagnetic ions in methanol and ethanol containing hydrochloric acid.Several results in methanol yielded values for actual solvent exchange (Meand OH protons showing equal effects) whereas the ethanol results gave noclear values (Me, CH,, and OH rates different).The alcohol-exchange ratewas lower than that obtained for water by oxygen-17 measurements.mEIectrochemicaI Methods.-In electrochemical methods the rate of achemical reaction is measured in competition with a rate of diffusion. It isfrequently found that only one of the reactants concerned in a chemicalequilibrium A + B += C is removed or formed at the electrode surface.The electrochemical reaction changes the concentration at the surface andthe species is then formed by diffusion and chemical reaction in a " reactionlayer " in the solution. In the simplest case the concentration of, say,reactant C, is reduced rapidly to zero at the electrode surface and the con-centrations of A and B are present in excess.In the experiments in whichreactant B is removed at the electrode surface the species A has usually beenmaintained constant by means of a buffer system so that the recombinationis a first-order process (see however below). Measurements have also beenmade by coupling the reaction to a further equilibrium B + X =+ Y , onlythe component Y undergoing an electrode reaction and X and Y againbeing present in excess.Most measurements have been carried out at mercury electrodes andthree different methods have been used: (1) the measurement of thecurrent-time transient by maintaining the electrode at constant poten-tial,101,102 (2) polarographic measurements of the mean current during thelifetime of a d r o ~ , ~ O ~ J ~ (3) measurements of the potential-time transient atconstant current.lm There has also been an investigation on p1atinum,lo6using the theory for a rotating-discThe polarographic case has been treated approximately by assuming avalue for the thickness of the reaction layer and that a stationary state isreached during the lifetime of each drop.lo3J08 There have been also moreexact treatments based on the solution of the differential equations governing100 See ref.6 in previous ref.lol H. Gerischer, 2. Ebktrochem., 1960, 64, 30.loa P. Delahay and S. Oka, J . Amev. Chem. SOC., 1960, 82, 329.lo3 R. BrdiEka and K. Wiesner, Coll. Czech. Chem. Comma., 1947, 12, 39, 138.lo4 J. Kouteck9 and R. Brdieka, Coll. Czech. Chem. Comm., 1947, 12, 337.loci L.Gierst and A. Juliard, J . Phys. Chetn., 1953, 57, 701; P. Delahay and T.lo6 W. Vielstich and D. Jahn, 2. Elektrochem., 1960, 64, 43.Io7 J,.Kouteckp and W. G. Lewitsch, 2hur.fiz. Khim., 1958, 32, 1565; R. R. Dogo-lo* V. HanuS, Chem. Zuesti, 1954, 10, 702.Berzins, J . Amer. Chem. SOL, 1953, '95, 2486, 4205.nadse, zbzd., 1958, 32, 2437100 GENERAL AND PHYSICAL CHEMISTRY.diffusion and reaction.lM,lo9 (For other reaction schemes see ref. 110.)The solution for the current-time transients [case (l)] is contained in thetreatment of the polarographic experiments.Electrochemical methods have been used largely to determine the ratesof formation and dissociation of metal complexes and of weak acids. Anexample in the first group which has been frequently studied is the dissoci-ation of the cyanocadmiate ion in the presence of excess of cyanide:kaCd(CN)d2- Cd(CN),- + CN-krThe tricyanocadmiate ion is the dominant species reduced. Measurementshave been made polarographically,111*112 galvan~statically,~~~ and potentio-statical1y.lo1 Recent results101~112 show a trend of the rate constant k,with potential, increasing negative potential decreasing the rate constant.This has been attributed to repulsion of the negative ion by the negativefield of the electrode when the thickness of the reaction ,layer becomescomparable to that of the diffuse double layer.This effect has been analysedrecently 112,114a and it has been shown that under limiting conditions theapparent rate constant varies exponentially with the diffuse double layerp0tential.114~ This potential can be varied by changing the electrodepotential or solution composition 112 and extrapolation to Yo = 0 gives avalue of k, = 5 x lo* 1.mole-l sec.-l.The rate of dissociation of weak acids has been measured frequently.Three methods have been used: (a) The preferential reduction of the un-dissociated acid has been measured polarographically in the presence ofexcess of the anion, a buffer system being used to maintain the concentrationof hydrogen ion constant .103J15, 116,117~118 (b) The rate of dissociation of theacid has been measured polar~graphically,~~~ potentiostatically,lo2 andgalvanostatically120 by determining the rate of reduction of a base, thereduction being specifically catalysed by hydrogen ions produced in thedissociation.Measurements have been made in (1 : 1) ethanol-water withazobenzene,120 and in water alone with +-nitr0aniline.m (c) A modificationIoD (a) J. KouteckJf, Coll. Czech. Chem. Comm., 1953, 18, 311, 597; 1954, 19, 1093;N. Landquist, Acta Chem. Scand., 1955, 9, 867; (b) J, Ciiek, J. Koryta, and J. Kouteckf,Coll. Czech. Chem. Comm., 1959, 24, 663; (c) Idem, ibid., 1959, 24, 3844.no R. BrdiEka, 2. Ekktrochem., 1960, 64, 17.J. Koryta, 2. Elektrochem., 1957, 61, 423.lls L. Gierst and €3. Hunvitz, 2. Elektrochem., 1960, 64, 36.113 L. Gierst and A. Juliard, J . Phys. Chem., 1953, 57, 701; P. Delahay, J . Amer.Chem. Soc., 1951,73, 1944; H. Gerischer, 2. Elektrochem., 1953,57,609; Idem, 2.phys.Chem., 1954, 2, 79.114 (a) H. Matsuda, J . Phys. Chem., 1960, 64, 336; see also H. Matsuda and P. Dela-hay, ibid., 1960, 64, 332; H. Matsuda, ibid., 1960, 64, 339, for effects on electrodereactions; (b) M. Breiter, M. Kleinermann, and P. Delahay, J . Amer. Chenz. Soc., 1958,80, 5111.116 R. BrdiCka, Coll. Czech. Chem. Comm., 1947, 12, 212.117 K. Wiesner, M. S. Wheatley, and J. M. Los, J . Amer. Chem. Soc., 1954, 76, 4858.118 J. Volke and V. Volkov& Coll. Czech. Chem. Comm., 1956, 20, 1332.119 P. Riietschi, 2. phys. Chem., 1955, 5, 323.180 P. Delahay arid W. Vielstich, J . Amer. Chem. Soc., 1955, 77, 4955.121 J. Giner and W. Vielstich, 2. Elektrochem., 1960, 64, 128.E. G. Clair and K. Wiesner, Nature, 1960, 165, 202BEWICK AND FLEISCHMANN : FAST REACTIONS IN SOLUTION.101of method (b) has been described122 in which the base (e.g., pyridine) isadsorbed on the electrode surface and there catalyses the reduction ofhydrogen ions produced by dissociation. The concentration of hydrogenions can again be reduced to zero at the electrode surface and the dissociationmade rate-determining.Whereas the rates of recombination of the carboxylate anions andhydrogen ions as determined by other methods are usually diffusion con-trolled, the rates measured electrochemically by method (a) are frequentlysmaller 115,116 or larger 118 by orders of magnitude. Of the examples whichgive low rates many are or-keto-carboxylic acids related to pyruvic acid, andit has been suggestedlz3 that the low rate constants may be due to the factthat only the unhydrated form is reduced.In the case of pyruvic acidcorrection for this gives rate constants of the correct order. Rate constantslarger than that for diffusion control are not possible. Acids giving highrate constants are frequently dibasic or contain heterocyclic nitrogenb a s e ~ , ~ ~ 7 J ~ e.g., imidazole which can exist in several forms including zwit-terions. These groupings may well transfer hydrogen ions to the carboxylateanion at an anomalous rate. Other reasons for the discrepancy have beenlisted126 (see further references in refs. 125, 110). Most of these cannotexplain why the rate constants are too large. Possible explanations are:(1) The reaction layer may be too thin for the normal laws of diffusion toapply.(2) In determinations by method (a) the anions may react withacids other than the hydrogen ion;126 that is, there may be general acidcatalysis. Recently solutions have been obtained for the diffusion equationswhich do not depend on the presence of excess of reactants logbsC and thesehave been generalised to include the reaction logb A + B C + D.These solutions should allow measurements in the absence of buffer systemsand have so far been applied to measure the rate of dissociation logb of thecadmium complex with nitrilotriacetic acid and the rate of dissociationcatalysed by hydrogen ions.1o9c (3) Adsorbed molecules may take part inthe reaction. There have been several investigations recently on theeffects of adsorption of inhibitors or of the reactants on the discharge stepitself .l27It must be noted, however, that where direct comparison is possible theresults obtained electrochemically [by method (b)] and by relaxationmeasurements agree reasonably well.102,121 In these cases both techniquesin essence measure the rate of dissociation.The polarographic method has also been used for a wide variety ofreactions in solution amongst which are the acid-base catalysed dehydrationlZ2 H.W. Nurnberg, G. van Riesenbeck, and M. von Stackelberg, 2. Elektrochem.,lZs M. Becker and H. Strehlow, 2. Elektrochem., 1960, 64, 129.la4 E.g., J. KQta and E. KejEi, Coll. Czech. Chem. Comm., 1959, 24, 268; 0. Hrdy,lZs J. Koryta, 2. Elektrochem., 1960, 64, 23; H.Strehlow, ibid., 1960, 64, 45.lZ6 M. Becker and H. Strehlow, 2. Elektrochem., 1960, 64, 42.lZ7 See e.g., J. Weber, J. Koutecky, and J. Koryta, 2. Ebkfrochem., 1959, 8s. 583;J. Weber, J. Kbta, and J. Kouteckp, Coll. Czech. Chem. Cornm., 1960,25,2376; J . Kbtaand I. Smoler, 2. Elekfrochem., 1960, 64, 285; I. M. Kolthoff and J. Okinaka, J . Amer.Chem. Soc., 1959,81,2296; H . Matsuda and P. Delahay, Coll. Czech. Chem. Comm., 1960,25,2977; for other references see A.ran.ual Reports, 1968.1960, 64, 130.ibid., 1959, 24, 1180102 GENERAL AND PHYSICAL CHEMISTRY,of the hydrate of forrnaldehyde,lB the acid-base catalysed conversion ofcyclic acetals into the carbonyl form of sugars,12g the formation of metalcomplexes,lm and the oxidation of ferrous ions 131 and of the complex withethylenediaminetetra-acetic acid 132 by hydrogen peroxide.It can be seen that the variety of methods which have been developedhas extended the accessible time scale by about ten powers of ten.Thestatements “ the reaction is immeasurably fast ” or ‘‘ the reaction is in-stantaneous ’’ can now be qualified or, in the limit, replaced by “ the reactionis diffusion controlled.”The Reporters thank their colleagues for helpful discussions and advice.A. B.M. F.9. PHYSICAL PROPERTIES OF POLYMERSTHE properties of polymer solutions were last reviewed in 1950,l but noprevious report has considered polymers in bulk. We shall deal mainlywith linear organic polymers, inorganic and biological materials and resinswill be excluded.Recent monographs 2 present the principles of the subject, and usefulguides to problems of current interest are found in the published proceedingsof several conferences.3The introduction of stereoregular polymers has opened up a new aspectin polymer science, since it is now clear that the degree of stereospecificityhas an important influence on the properties of macromolecules.Un-fortunately, experimental determination of this parameter presents a majorproblem, although several techniques offer possible solution^.^-^Polymer SolutionsExcellent reviews of polymer solutions have been given recentlyby Casassa8 and St~ckmayer.~ The practical aspects of studies of128 R. BrdiEka, Coll. Czech. Chem. Comm., 1955, 20, 387.la9 J. M. Los and K.Wiesner, J . Amer. Chem. Soc., 1953, 75, 6346; J. M. Los, L. B.130 J. Koryta, Coll. Czech. Chem. Comm., 1959, 24, 3057; J. Biemut and J. Koryta,131 2. Popisil, Coll. Czech. Chem. Comm., 1955, 18, 337.133 B. Matyska, Coll. Czech. Chem. Comm., 1957, 22, 1758.Simpson, and K. Wiesner, ibid., 1956, 78, 1564.ibid., 1960, 24, 38.C. E. H. Bawn, A m . Reports, 1950, 47, 85.P. J. Flory, “ Principles of Polymer Chemistry,” Cornell University Press, Ithaca,N.Y., 1953; A. V. Tobolsky, “ Properti? and Structure of Polymers,” John Wiley &Son Inc., New York, 1960; H. Tompa, Polymer Solutions,” Butterworths, London,1956; L. R. G. Treloar, “ Physics of Rubber Elasticity,” Oxford University Press,1959.3 I.U.P.A.C., 1958, Meeting, J . Polymer Sci., 1959, 34; 1959 Meeting, Makyomol.Chem., 1959-60, 34, 35, 35, A .4 D.W. McCall and F. A. Bovey, J . Polymer Sci., 1960, 45, 530; A. Nishioka andH. Watanabe, ibid., 1960, 45, 232.6 U. Baumann, H. Schreiber, and K. Tessmar, Makromol. Chem., 1960, 38, 81;M. Takeda, K. Imura, and A. Yamada, Bull. Clzem. SOC. Jafian, 1960, 33, 1219; B. 2.Volchek and Zh. N. Robberman, Vysokomol. Soedineniya, 1960, 2, 1157.6 S. Okamura and T. Higashimura, J . Chem. Phys., 1960, 33, 631.7 V. I?. Tsvetkov and N. N. Bietsova, Vysokomol. Soedineniya, 1960, 2, 1176.9 W. H. Stockmayer, Makromol. Chem., l§€iO, 55, 54.E. F. Casassa, Ann. Rev. Phys. Chem., 1960, 11, 477ALLEN AND JONES: PHYSICAL PROPERTIES OF POLYMERS. 103polymer solutions have been treated in a publication edited by P.W.Allen.10Concentrated Polymer Solutions.-The Flory-Huggins lattice theory stillremains the only theory applicable to concentrated polymer solutions,although its deficiencies are now well established. A comprehensive studyof the system polystyrene-cyclohexane has been made by Krigbaum andGeymer," showing that the partial molar heat of dilution is not adequatelyrepresented by a single van Laar term, as expressed in the Flory-Hugginstheory.A non-statistical theory of solutions which should be applicable tosolutions of substances of low molecular weight as well as high polymers hasbeen formulated by Maron.l2 This is equivalent to the Flory-Hugginstheory but takes into consideration the volume change on mixing. Maronand Nakajima l3 have applied the theory successfully to the rubber-benzenesystem,l* and Cerry et aZ.15 have shown that the osmotic pressures of a seriesof polyvinylpyrrolidones in aqueous solution can be adequately representedby Maron's expressions.Conway and Lakhanpal 16 have reported results on the polar polyrner-polar solvent system, polypropylene oxide-methanol, where specific inter-action leads to large departures from random mixing.Gornick and Hughes 1' have considered the statistical thermodynamicsof partially tactic polymers and modified the Flory-Huggins theory to takeinto account the stereoisomeric structure of the polymer chain.The viscosity of moderately concentrated polymer solutions (< 20%)and extremely concentrated solutions (> 20y0) has been investigated byHirai,l* and the osmotic pressures of moderately concentrated polymersolutions have been considered by Fixman.l9Properties of Dilute Solutions.4hai.n conformatiort.The properties ofdilute polymer solutions are greatly influenced by the configuration of thepolymer chains, and consequently the influence of chemical structure andsolvent interaction on chain configuration is of fundamental importance.Such effects are intimately related to the thermodynamic and rheologicalproperties of polyrner solutions, and are made manifest in measurablequantities such as the osmotic-pressure and light-scattering second virialcoefficients and the limiting viscosity number [q].The mean-square end-to-end distance of a polymer chain in solution (T2)departs from its random flight value because of two effects, (a) short-rangeinteractions resulting from hindered rotations of the chain elements andlo P.W. Allen, " The Characterisation of High Polymers," Butterworths, London,l1 W. R. Krigbaum and D. 0. Geymer, J . Amer. Chem. SOC., 1959,81, 1859.la S. H. Maron and N. Nakajima, J. PoZymer Sci., 1959, 40, 59.l4 G. Gee and L. R. G. Treloar, Trans. Faraday SOC., 1942, 38, 147.l5 L. C. Cerry, T. E. Helminiak, and J. F. Meier, J . Polymer Sci., 1960, 44, 539.l6 B. E. Conway and M. Lakhanpal, I.U.P.A.C. Symp. on Macromolecules, Wies-l7 F. Gornick and R. E. Hughes, Amer. Chem. SOC., Cleveland Meeting, 1960, 1,I * N. Hirai, J. Polymer Sci., 1959, 89, 435; 1969, 40, 255.lD M. Fixman, T.U.P.A.C.Symp. on Macromolecules, Wiesbaden, 1969.1959.S. H. Maron, J . Polymer Sci., 1959, 38, 329.baden, 1959.249104 GENERAL AND PHYSICAL CHEMISTRY.(b) long-range effects arising from polymer-solvent interactions which giverise to the excluded volume. Kurata et aL20 have shown that the expansionof the chain, due to the excluded volume effect, does not occur uniformly andas a result the distribution of segments is no longer Gaussian.There are two principal expressions for the molecular expansion factor ain the equation T2 = 6a2, where 3 is the unperturbed mean-square end-to-end distance: a series expansion in terms of the excluded volume and therandom-flight dimensions applicable only near the Flory 8 temperat~re,~ *and expression (1) first derived by Flory.A discussion of the magnitudect5 - a3 = constant x n* . . . . . . (1)of the constant in eqn. (1) has been given by St~ckmayer,~ and a new expres-sion for a in a good solvent system has been derived by Kurata et aL21 onthe basis of an ellipsoidal distribution of chain elements. The results are inagreement with the “ Monte Carlo ” calculations of Wall and Erpenbeck 22and also experimental results for the systems polystyrene-benzene andpoly isobut ene-c y clo hexane .The solvent effect on internal rotations of polymer molecules has beenconsidered by Oppenheim and Lifson,= and methods for the calculation ofunperturbed polymer dimensions have been given by Hoeve.%A review of chain configuration studies has been given by Vol’ken-~ h t e i n .~ ~The influence of chemical structure on the unperturbed molecular dimen-sions of polymer molecules determined by light-scattering measurementshas been investigated. Krigbaum et have shown that the volumepervaded by an isotactic molecule of polystyrene is 25-30% larger thanthat for the atactic molecule. Chinai et aL2’ have studied a series of meth-acrylates in ideal solvents and ideal solvent mixtures and conclude that thependant group -C02R, where R = Me, Et, etc., extends the chain in theorder n-lauryl > n-hexyl > n-octyl > Bun > Et > Me: the reason for thereversal of order from that expected in the case of octyl and hexyl meth-acrylates is unknown. It is clear from Chinai’s work that accurate deter-mination of the 8 temperature is essential to obtain meaningful results.Themeasurements show that the unperturbed dimensions are uninfluenced bythe size and shape of the solvent molecule. In contrast, some doubt isthrown on the use of 0 solvents for the determination of the unperturbed20 M. Kurata, H. Yamakama, and H. Utiyama, Makromol. Chem., 1960, 34, 139.21 M. Kurata, W. H. Stockmayer, and A. Roig, Amer. Chem. SOC., Cleveland Meet-22 F. T. Wall and J. J. Erpenbeck, J . Chem. Phys., 1959, 30, 634.23 I. Oppenheim and S. Lifson, Amer. Chem. SOC., Cleveland Meeting, 1960, 1, 215.24 C. A. J. Hoeve, J . Chem. Phys., 1960, 32, 888.25 M. V. Vol’kenshtein, J . Polymer Sci., 1958, 29, 441.26 W. R. Krigbaum, D. K. Carpenter, and S. Newman, J . Phys.Chem., 1958, 62,1586.27 S. N. Chinai and R. A. Guzzi, J . Polymer Sci., 1959, 41, 475, and earlier paperslisted therein.* Schulz et al. [Z. phys. Chem. (Frankfurt), 1960, 24, 3901 have shown that at theFlory 0 temperature (where u = 1) the solution is not ideal but pseudo-ideal, theenthalpy and entropy of dilution being mutually compensated a t this temperature.ing, 1960 1, 229ALLEN AND JONES: PHYSICAL PROPERTIES OF POLYMERS. 105dimensions of very polar molecules by Ivin's 28 results for hex-l-ene poly-sulphone: here 3 depends on the relative polarities of the polymer and 0solvent.Light-scattering and related studies on polyvinyl et hers,29 polysil~xanes,~~poly-2,5-di~hlorostyrene,~~ p~lyamides,~~ crepe rubber,33 cellulose tri-hexanoate,M p~ly-Z-vinylnaphthalene,~~ high-pressure p~lyethylene,~~ un-fractionated poly (vinyl acetate) :7 poly(ethy1ene terepht halate), and poly-(1, 4-cyclohexylenedimethylene) 38 have also appeared.The osmotic pressure (n) of a polymer solution can be represented by thevirial expressionThe corresponding expression applicable to light-scattering is.. . . . . . . nlc = RT(l/ii?, + A2c .) (2)where H , 7, an, Mw, have their usual significance. A , and A,', the corre-sponding second virial coefficients, are functions of the excluded volume,and take into consideration single contacts between two polymer molecules.Albrecht 39 has shown that if double contacts in bimolecular clusters areincluded in the calculation of A2', the coefficient of the second term in thelight-scattering eqn.(3) involves the product of A,' and a function Q(0) whichbecomes unity at 8 = 0. Thus virial coefficients determined from scatter-ing at 90" only, will decrease too rapidly with molecular weight and bedependent on the wavelength of light used, as has been observed by Chinai2'In general A , = A,' only for homogeneous polymers, and Yamakawa andKurata 40 have calculated their values for heterogeneous polymers withboth Schulz 41 and two delta-peak molecular-weight distributions. Anexpression for the second virial coefficient, account being taken of thepositions of the various chain segments resulting from its connected nature,has been given by Krigbaum et aZ.42Danusso and Moraglio 43 found that the value of the second virial coeffi-cient for isotactic polystyrene in toluene is greater than that for the atacticmaterial of the same molecular weight.This can be explained in terms ofthe larger unperturbed dimensions for the isotactic molecule.2628 J. A. Mason and G. J. Arquette, Makromol. Chem., 1960, 37, 187.3o V. S. Skazka and L. G. Schaltyko, Vysokomol. Soedineniya, 1960, 2, 571.81 V. E. Eskin and J. 2. Gumargaliera, Vysokomol. Soedineniya, 1960, 2, 265.32 H. C. Beachell and D. W. Carison, J . Polymer Sci., 1959, 40, 543; D. W. Carlson,88 Von K. Altgelt and G. V. Schulz, Makromol. Chem., 1960, 36, 209.84 W. R. Krigbaum and L. H. Sperling, J . Phys. Chem., 1960, 64, 99.85 R. A. Mendelson, Amer. Chem. SOC., Cleveland Meeting, 1960, 1, 272.39 A. C.Albrecht, J . Chem. Phys., 1957, 27, 1014.*O H. Yamakawa and M. Kurata, J . Chem. Phys., 1960, 32, 1852.*l G. V. Schulz, 2. Phys. Chem., 1939, B, 43, 25.42 W. R. Krigbaum, D. K. Carpenter, A. Roig, and M. Kaneko, I.U.P.A.C. Symp.43 F. Danusso and G. Moraglio, J . Polymer Sci., 1957, 24, 161.K. J. Ivin, personal communications.Diss. Abs., 1960, 20, 2577.V. E. Eskin and 0. 2. Korotkina, Vysokomol. Soedineniya, 1959, 1, 1580; 1960,R. A. Ahlbeck, I.U.P.A.C. Symp. on Macromolecules, Wiesbaden, 1959.L. D. Moore, jun., Amer. Chem. SOC., Cleveland Meeting, 1960, 1, 234.2, 272.on Macromolecules, Wiesbaden, 1959106 GENERAL AND PHYSICAL CHEMISTRY.The second virial coefficient of a solution of two sharp fractions of thesame polymer in a good solvent as a function of solute composition passesthrough a maximum if the interaction coefficient of the unlike species isgreater than the interaction coefficient of either like species.This maximumhas been confirmed by Casassa for the systems polyisobutene-cyclohexaneand polystyrene-toluene.44The angular distribution of scattered light for polydisperse Gaussiancoils45 and rigid rods,% and the effect of polydispersity on the end-to-enddistribution function for free-rotating chains 47 have been calculated byKolbovskii. New tables of light-scattering functions for use in the determin-ation of molecular dimensions and molecular weights have also appeared.**The determination of the size and shape of macromolecules i.n solutionfrom small-angle X-ray scattering has been considered by K r a t k ~ , ~ ~ andthe scattering function which enables the persistence length of a chain tobe determined by this method has been calculated by Peterlin.50Measurements of molecular interaction from angular distribution ofcritical opalescence have been reported by D e b ~ e .~ lA study of the ultraclarification of aqueous solutions has been made,52and a review of light-scattering methods for chemical characterisation ofpolymers has been given by Peaker.53Rheological +roperties. Study of the rheological properties of polymersolutions furnishes a further insight into the behaviour of polymer moleculesin solution. The existence of an excluded-volume effect resulting in adeparture from a Gaussian distribution of chain elements necessitates themodification of the Kirkwood-Riseman theory for the limiting viscositynumber.A survey of methods of determination of molecular size and shape fromrheological experiments has been given by P e t e r l i ~ ~ , ~ ~ and the non-Gaussiancoil dimensions of a fractionated polystyrene sample in a number of differentsolvents have been determined by Meyerhoff .56It has been reported that the Mark-Houwink constants are identicalfor atactic and isotactic polypropene 57 (cf.polystyrene &) in a thermo-dynamically good solvent even though measurements of the second virialcoefficient indicate that the two geometrical isomers are in different thermo-dynazic environ-ments. Koningsveld and Tuij nman 58 have obtained[+Mn and [q]-MW functions, showing a sensitivity to the width of theSuch effects have been discussed by Kurata et aL2044 E.F. Casassa, Polymer, 1960, 1, 169.45 Yu. Ya. Kolbovskii, Vysokomol. Soedineuaiya, 1960, 2, 85, 825.413 Yu. Ya. Kolbovskii, Vysokomol. Soedineniya, 1960, 2, 1154.47 Yu. Ya. Kolbovskii, Vysokomol. Soedineniya, 1960, 2, 828.48 W. H. Beattie and C. Booth, J . Phys. Chem., 1960,64, 696; J . Polymer Sci., 1960,49 Von 0. Kratky, Angew. Chem., 1960, 72, 467; Makromol. Chem., 1960, 35, A , 12.5O A. Peterlin, Amer. Chem. SOC., Cleveland Meeting, 1960, 1, 208.51 P. Debye, Makromol. Chem., 1960, 35, A , 1.52 M. M. Huque, J. Jaworzyn, and D. A. I. Goring, J . Polymer Sci., 1959, 39, 9.53 F. W. Peaker, Analyst, 1960, 85, 235.54 J. G.Kirkwood and J. Riseman, J . Chem. Phys., 1948, 16, 565.5 5 A. Peterlin, Makromol. Chem., 1959, 34, 89.56 G. Meyerhoff, Makromol. Chem., 1960, 37, 97.5' I. B. Kingsinger and R. E. Hughes, J . Phys. Chem., 1959, 63, 2002.jS R. Koningsveld and C. A. F. Tuijnman, Makvomol. Chem., 1960, 32, 1739.44, 81ALLEN AND JONES: PHYSICAL PROPERTIES OF POLYMERS. 107molecular-weight distribution ; and [q]-molecular-weight data for lowpressure polyethylene and poly(viny1 acetate) have been analysed, molecularheterogeneity being considered.The influence of temperature on the viscosity of solutions of polystyrenein toluene has enabled the thermodynamic parameters of the system to beevaluated by Bianchi and Magnas~o,~~ and the significance of the maximumin the [+T curve for polymers has been further considered by Kawai andUeyama.60Measurements of viscosity and flow birefringence of poly(buty1 meth-acrylate) in propan-2-01 over a range of temperature have shown that,although the molecular dimensions increase considerably with temperatureowing to increase in long-range interactions, the shape asymmetry of themolecular coils in solution is practically unaffected.61A theory has been formulated for the light scattering of rod-like macro-molecules in a liquid subjected to shear.62 This provides a direct method ofstudying the behaviour of particles in a flowing medium.A new method has been suggested for plotting viscometry data forpolymer solutions.=Osmosis. Although the theory of osmotic-pressure measurements iswell established, the influence of membranes on the results is still a problem,and an extensive review of this topic has been given by Patat.a A theoryhas also appeared for osmotic measurements made with solute-permeablemembrane^.^^Ultracentrifugation. Fujita 66 has suggested a new method for thedetermination of average molecular weights and molecular-weight distri-butions of polymers from sedimentgion equilibrium experiments in 8 sol-vents, this allows the calculation of M,.Gupta and Goring 67 have reportedthat for polydisperse alkali lignins the sedimentation coefficient is a functionof the centrifugal field, and suggest that this is due to polydispersity andshould be observed with all widely polydispersed systems where the concen-tration dependence of the sedimentation constant is small.Application of sedimentation-diffusion equilibrium experiments to theevaluation of polymer-solvent interaction in the system polystyrene-cyclohexane at the Flory 8 temperature has been made by Fujita et aZ.68It is apparent that ultracentrifugation studies 69, 70 are rapidly supplementinglight-scattering and osmotic-pressure measurements as a means of investigat-ing thermodynamic properties of polymer solutions.5s U.Bianchi and V. Magnasco, J . Polymer Sci., 1969, 41, 177.60 T. Kawai and T. Ueyama, J . Appl. Polymer Sci., 1960, 3, 227.61 V. N. Tsvetkov and S. Ya. Lyubina, Vysokomol. Soedineniya, 1960, 2, 75.62 K. Okano. E. Wada, and W. Heller, Amer. Chem. SOC., Cleveland Meeting, 1960,63 C.Mussa and V. Tablino, Polymer, 1960, I, 266.64 F. Patat, Makromol. Chem., 1959, 34, 120.65 Ch. A. Kruissink, I.U.P.A.C. Symp. on Macromolecules, Wiesbaden, 1959.68 H. Fujita, J . Chem. Phys., 1960, 32, 1739.6' P. R. Gupta and D. A. I. Goring, J . Chem. Phys., 1960, 32, 1890.H. Fujita, M. Linklater, and J. W. Williams, J . Amer. Chem. SOL, 1960, 82, 379.89 G. Meyerhoff, Angew. Chem., 1960, 72, 699.70 J. W. Williams, K. E. Van Holde, R. L. Baldwin, and H. Fujita, Chem. Rev.,1, 212.1958, 58, 715108 GENERAL AND PHYSICAL CHEMISTRY.Phase separation. A new class of lower critical solution temperatures forpolymer solutions has been reported.71It is well known that phase separation occurs in systems containing twopolymers and a common solvent.Recent measurements attribute thisphenomenon to departures from random mixing arising from a partial segreg-ation of the different polymer chains.72 Phase equilibrium in polymersolutions has been reviewed by V O O ~ ~ . ~ ~Polymers in BulkCrystalline State.-Stereospecific isomers of many amorphous polymershave been prepared, thus expanding the range of crystallizable materials.X-Ray studies suggest that the crystallites are embedded in an amorphousmatrix, the degree of crystallinity being influenced by past history and degreeof stereoregularity of the specimen. Difficulties arising in the determinationof the extent of crystallization are emphasized in recent paper^.^^-'^Chain conjgwation. Crystallographic data have been collected for-50 polymer^.^^-^^ Current reports deal with syndiotactic polypropene,slisotactic poly-m-methylstyrene,s2 nitro styrene^,^^ -oxymethylene,a -pro-pylene oxide,s5 and -epichlorohydrin.86 Additional information has beenobtained from infrared studies on isotactic poly-pr~pene,~~ -styrene,79-propylene oxide, -butadiene monoxide, -styrene oxide,!js and syndiotacticpoly-1,2-b~tadiene.~~ In this connection, Krims9 has shown that, if astructural unit has two mutually perpendicular transition moments, it ispossible to determine uniquely the orientation of the moments relative tothe axis of the polymer chain.The factors determining chain configuration in crystals have been dis-CUSS^^.^^^^^^^^ Planar zig-zag or helical structures are common and the71 P.I. Freeman and J. S. Rowlinson, Polymer, 1960, 1, 20; P. EhrIich and E. B.Graham, J . Polymer Sci., 1960, 45, 246.78 G. Allen, G. Gee, and J. P. Nicholson, Polymer, 1960, 1, 56; G. M. Bristow,J . Appl. Polymer Sci., 1959, 2, 120.73 M. J. Voorn, Fortschr. Hochpo1ym.-Forsch., 1959, 1, 192.74 G. Farrow and I. M. Ward, Brit. J . Appl. Phys., 1960, 11, 543.75 P. R. Swan, J . Polymer Sci., 1960, 42, 625.76 M. Kakudo and R. Ullman, J . Polymer Sci., 1960, 45, 91; P. H. Hermans and77 E. M. Bradbury, A. Elliott, and R. D. B. Frazer, Trans. Furaday Soc., 1960, 56,78 R. L. Miller and L. E. Nielsen, J . Polymer Sci., 1960, 44. 391.79 G. Natta and P. Corradini, Naovo ckm., Suppl., 1960, 15, 3-138.80 C. W. Bunn and D. R. Holmes, Discuss. Furuday Soc., 1958, 25, 95.81 G.Natta, I. Pasquon, and P. Corradini, Atti Accud. nuz. Lincei, Rend. Classe Sci.88 P. Corradini and P. Ganis, J . Polymer Sck., 1960, 43, 311.83 A. S. Matlack and D. S. Breslow, J . Polymer Sci., 1960, 45, 265.84 H. Tadokoro, T. Yasumoto, S. Murashi, and I. Nitta, J . Polymer Sci., 1960, 44,85 E. Stanley and M. Litt, J . Polymer Sci., 1960, 43, 453.86 S. Ishida, Bull. Chem. Soc. Japan., 1960, 33, 727.87 C. Y . Liang and F. G. Pearson, J . Mol. Spectroscopy, 1960, 5, 290; M. C. Tobin,A. Kawasaki, J. Furukawa, and T. Tsuruta, Polymer, 1960, 1, 315.S. Krim, J . Chem. Phys., 1960, 32, 313.S. Sakaguchi, Chem. High Polymers (Japan), 1960, 17, 333.A. Weidinger, Mukromol. Chem.. 1960, 39, 67.1117.jis. mat. nut., 1960, 28, 539.267.J .Phys. Chem., 1960, 64, 216ALLEN AND JONES: PHYSICAL PROPERTIES OF POLYMERS. 109actual conformation usually corresponds to the one representing minimumpotential energy of an isolated chain. In some casesm intermolecularforces and packing considerations appear to influence the ultimate con-figuration.Although stereoregularity is generally accepted as a cause of crystallinityin polymers, Case 91 finds that experiments on the deuteration of hydrogenatoms on tertiary carbons in isotactic polypropene do not support this view.He suggests that stereospecific catalysts may simply produce linear mole-cules and that lack of side branches is primarily responsible for the highdegree of crystallinity. It is difficult to reconcile this observation with thecrystallographic evidence and more work is clearly desirable.Treloar 92 has calculated the elastic moduli of polyethylene, poly(ethy1eneterephthalate) , nylon-66, and cellulose crystals, using published crystallo-graphic data and force constants transferred from small molecules.Thecalculations, which neglect secondary forces, give moduli higher than theexperimental values for the first three polymers. For cellulose the calcu-lated value is lower in spite of the fact that there is no obvious reason whythe secondary forces should be so significant in this case.Single crystals. Precipitation of polymers from super-cooled dilute solu-tion, in the form of lamellar single crystals, has been observed for poly-ethylene,93,94 -pr~pene,~*y~~ -4-methylpent-l-ene,% -styrene,95 -oxy-meth~lene,~' and nyl0n-6.~8 The polyethylene crystal has also been de-scribed as a hollow pyramid.99 In every case the crystals consist of regularlayers -100 thick, with sharply folded chains oriented perpendicularlyto the flat surfaces.Recrystallization occurs by chain refolding 100 whenthe single crystals of polyethylene are annealed at 1 0 4 0 " ~ below themelting point (Tm), increasing the layer thickness to 200-3OOw. Thusthere seems to be a surprising degree of molecular mobility below T , andthis has been confirmed by nuclear magnetic resonance studies.lOl Explan-ations of these folded-chain structures have been based on considerationsof nucleation and growth of the crystals from solution lo2 but Peterlin lo3claims that according to these theories the thickness of the layers shouldincrease indefinitely on annealing.He considers that regular chain folding91 L. C. Case, J . Polymer Sci., 1960, 45, 435.s2 L. R. G. Treloar, Polymer, 1960, 1, 95, 279, 290.A. Keller, Mukromo2. Chern., 1969, 34, 1 ; A. Keller and A. O'Connor, Polymer,94 B. G. Ranby, F. F. Morehead, and N. M. Walter, J . Polymer Sci., 1960,s5 V. A. Kargin, N. F. Bakeev, and Li Li-sten, Vysokomol. Soedineniyu, 1960, 2,s6 F. C. Frank, A. Keller, and A. O'Connor, Phil. Mag., 1959, 4, 200.97 P. H. Geil, N. K. Symons, and R. G. Scott, J. Appl. Phys., 1969, 30, 1516.g8 P. H. Geil, J . Polymer Sci., 1960, 44, 449.W. D. Niegisch and P. R. Swan, J . AppZ. Phys., 1960, 31, 1906; D.H. Renekerloo P. H. Geil and W. 0. Statton, J . Ap9.L Polymer Sci., 1960, 3, 367; W. 0. Statton,lol W. P. Slichter, J . Appl. Phys., 1960, 31, 1866.loa J. I. Lauritzen and J. D. Hoffman, J . Res. Nut. Bur Stand., 1960, 64, A, 73;l0s A. Peterlin, J. Appl. Phys., 1960, 31, 1934.1960, 1, 163.44, 349.1280.and P. H. Geil, ibid., p. 1916.and P. H. Geil, Amer. Chem. SOC., Cleveland Meeting, 1960, 1, 24.F. P. Price, J . Polymer Sci., 1960, 42, 49110 GENERAL AND PHYSICAL CHEMISTRY.is achieved by a balance of the surface free-energy contribution tending toproduce thick layers and the anisotropic molecular force field favouring thincrystals.MeZtiHg phenomena. Fusion in polymers is generally observed as adiffuse first-order transition.lM However, dilatometric techniques give awell-defined temperature at which the last traces of crystallinity disappear,providing that the specimen is previously annealed and a slow rate ofheating is maintained (Mandelkern lO4) a Similar considerations apply tothe use of differential thermal analysis lo5 and calorimetry.lM Chiang andFlory lo6 used a dilatometric method to study linear polyethylene; 80% of acarefully fractionated sample, of i%!fv = 32,000, melted in a range of 2" c.The upper limit for Tm of linear polyethylene of high molecular weightwas estimated as 139.7" c.The effect of chain branching has also beeninvestigated.lo7 Variations in Tm of 5-10" are reported for other polymers,but Coleman lo* attributes some of these discrepancies to different degreesof stereoregularity. Isotactic poly-(4-methylpent-l-ene) is unusual: log it hasa normal melting transition at 250" but at room temperature the crystallinephase has a lower density than the amorphous material.Heats and entropies of fusion for polystyrene and poly(viny1 fluoride)can be added to Dole's compilation.lw The pressure dependence of T, hasbeen measured for poly-(propylene oxide) and -(ethylene oxide) .ll1 Someinterest in the configurational contribution to the entropy of fusion ofpolymer crystals has developed; 112 accordingly experimental estimates ofentropies of fusion at constant volume have been made for polyethylene,natural rubber, gutta percha, polytetrafluoroethylene, polyoxymethylene,lWand polystyrene.ll0 Mandelkern et aZ.113 find that cross-linking betweenoriented chains in polyethylene and in natural rubber depresses T, less thanin the corresponding networks formed from random chains, owing to thelower configurational entropy of the liquid state of the oriented specimen.Specific-heat data have also been collected by Dole,lM and Stockmayerand Hecht's theory has been fitted to the results for poly-ethylene and-tetrafluoroet hylene.l14Amorphous States.-Two states are usually distinguished: the rubberwith molecular mobility similar to that of a liquid, and the glass which ischaracterized by frozen-in disorder.Kinetic theory of elasticity.Appraisals of the theory have been published104 L. Mandelkern, Chew. Rev., 1956,56, 903; M. Dole, Fortschr.Hochpolym.-Forsch.,105 B. Ke, J . Polymer Sci., 1960, 42, 15; N. D. Scott, Polymer, 1960, 1, 114.lo6 R. Chiang and P. J. Flory, Amer. Chem. SOC., New York Meeting, 1960,107 K. Tanaka, Bull. Chem. SOC. Japan, 1960, 53, 1060, 1133.lo* B. D. Coleman, J . Polymer Sci., 1958, 31, 155.109 J. H. Griffith and B. G. Ranby, J . Polymer Sci., 1960, 44, 369.110 F. Danusso and G. Moraglio, Atti Accud. nuz. Lincei, Rend. CZusse Sci. $2. mat.111 L. R. Fortune and G. N. Malcolm, J . Phys. Chem., 1960, 64, 934.G. Gee, Proc. Chem. SOC., 1957, 111; H. W. Starkweather and R. H. Boyd, J .lls L. Mandelkern, D, E. Roberts, and J. C. Halpin, J . A m y . Chem. Spc., 1960, 82,114 H. W. Starkweather, J . Polymer Sci., 1960, 45, 525,1960, 2, 173.1, 181.nut., 1959, 27, 381; D.I. Sapper, J . Polymer Sci., 1960, 43, 383.Phys. Chem., 1960, 64, 410.46; D. E. Roberts and L. Mandelkern, ibid., p. 1091ALLEN AND JONES: PHYSICAL PROPERTIES OF POLYMERS. 111by Treloar 2~116 and Tobolsky.2 The stress f developed in a network de-formed to an extension ratio a is formulated asf = c(a - l/a2) . . . . . . .where c is characteristic- of the network structure. An expression derivedfrom a phenomenological argument is said 115 to give better agreement withexperiment , viz. :f = cl(a - 11.2) + c2(1 - 11~3) . . . .It is now reported 116 that eqn. (5) holds only for extension and not for thesubsequent retraction. Further, cz is independent of the amount of crosslinking and is reduced by swelling or by working at temperatures wellabove the glass transition.Consequently the necessity for the second termmay arise from non-attainment of equilibrium under normal experimentalconditions. Flory’s treatment of network flaws has been reconsidered byS~an1an.l~~ A more rigorous analysis by Case117 suggests that Flory’smethod overestimates the number of active chains. A generalized theory ofthe elasticity of a composite network, formed by introducing a second set ofcrosslinks whilst the network is under strain, has been developed,ll* and itsapplication to stress relaxation occurring under conditions of simultaneousrupture and re-formation of cross-links is discussed.A series of papers 116*119 deals with the analysis of thermo-elastic data.Attention is drawn to the fact that the approximationmay lead to serious errors.Thus, (g) is not necessarily zero for poly-dimethylsiloxane as previously reported. In fact Ciferri 119 infers that themean dimensions of the silicone chain increase with temperature.Static properties. Published data on densities and coefficients of expan-sion are notoriously inconsistent. Lack of care in removing traces ofsolvent and use of excessive rates of heating seem to be two of the responsiblefactors. In general these properties rapidly become independent of mole-cular weight, and the effects of molecular-weight distributions do not appearto be pronounced, although chain branching can be important-notably inp01yethylenes.l~~ Coefficients of expansion have been collected for 12 poly-mers.120 The values range from 5 to 10 x lo4 deg.-l for rubbers and2 to 3 x 10-4 deg.-l for glasses.Specific heats are difficult to measure in theregion of the glass transition because of heat drifts; however Wunderlich 121ll6 L. R. G. Treloar, in Rheology of Elastomers,” Eds. P. Mason and N. Wookey,Pergamon Press, London, 1958.116 A. Ciferri and P. J. Flory, J. Appl. Phys., 1959, 30, 1498.11’ J. Scanlan, J. Polymer Sci., 1960, 43, 501; L. C. Case, ibid., 1960, 45, 397;P. J . Flory, Chem. Rev., 1944, 35, 51.11* P. J. Flory, Trans. Faraday SOC., 1960, 56, 722.11* P. J. Flory, C. A. J. Hoeve, and A. Ciferri, J . Polymer Sci., 1959, 34, 337; P. J .Flory, A. Ciferri, and C. A. J. Hoeve, ibid., 1960, 45, 235; A. Ciferri, ibid., 1960, 45, 528.lPo A.V. Tobolsky, ref. 2, ch. 2, p. 70.121 B. Wunderlich, J. Phys. Chem., 1960, 64, 1052.8, 112 GENERAL AND PHYSICAL CHEMISTRY.has analysed data for several compounds and correlated the increase inspecific heat in this region with structural features of the polymers.Cohesive-energy densities 120 and internal pressures l Z 2 have been estimatedfor the rubbery state of several polymers. For a glass the internal pressureis known to be lower than that of the corresponding rubber.lWJ23Glass transition (Tg) . Willbourn 124 has outlined the problem of definingTs for polymers which display several transition regions when investigatedby dynamic techniques. Gee 125 suggests that the term should be used torefer to the temperature at which the quasi-static properties change fromthose of a rubber to those characteristic of a solid.Recent d i l a t ~ m e t r i c , ~ ~ ~differential thermal analy~is,~O~J~~ and refractive-index studies showthat T, can be estimated with reasonable precision, although for poly-ethylene it is still a controversial issue, values of -1S0,107 -2lo,l2* -55°,129and -120” having been suggested. Variation of T, with deformationhas been studied dilatometrically; 125 the results are not inconsistent with athermodynamic analysis based on the freezing-in of disorder in the glass.An attempt has been made130 to relate Tg to molecular cohesion and thenumber of degrees of rotational freedom frozen in. A more comprehensivestatistical-mechanical treatment,131 based on the lattice theory, defines Tgas the temperature at which the chains become so stiff that the configura-tional entropy vanishes.Extensive use is made of wide-line nuclear magneticresonance spectroscopy,B2Jw allied to mechanical 135 and dielectric 136loss methods, to correlate observed transitions with molecular motion.Dynamic firoperties.lZ2 G.Allen, G. Gee, D. Mangaraj, D. Sims, and G. J. Wilson, Polymer, 1960,1, 456,lg4 A. H. Willbourn, Trans. Faraday SOC., 1958, 54, 717.lZ6 G. Gee, P. N. Hartley, J. B. M. Herbert, and H. A. Lanceley, Polymer, 1960,lZ8 J. J. Keavney and E. C. Eberlin, J . Appl. Polymer Sci., 1960, 3, 47.127 R. B. Beevers and E. F. T. White, Trans. Faraday SOC., 1960, 56, 744,12* F. Danusso, G. Moraglio, and G. Talamini, J . Polymer Sci., 1956, 21, 39.12@ R. Nakane, J . AppZ. Polymer Sci., 1960, 3, 124.lSo R. A. Hayes, Amer. Chem. SOC., New York Meeting, 1960, 1, 86.131 J. H. Gibbs and E. A. DiMarzio, J . Chem. Phys., 1958, 28, 373; E. A. DiMarzioand J. H. Gibbs, J . PoZymer Sci., 1959, 40, 121.132 J. G. Powles, Polymer, 1960, 1, 219; W. P. Slichter, Makromol. Chem., 1959,84, 67.l33 A. E. Woodward, J. A. Sauer, and A. Odajima, Amer. Chem. SOC., New YorkMeeting, 1960, 1, 63; D. Hindman and G. F. Origlio, J . Polymer Sci., 1959, 39, 556;A. E. Woodward, R. E. Glick, J. A. Sauer, and R. P. Gupta, ibid., 1960, 45, 367; A. E.Woodward, J. M. Crissman, and J. A. Sauer, ibid., 1960,44,23; C. M. Huggins, L. E. St.Pierre, and A. M. Bueche, J . Phys. Chem., 1960, 64, 1304; D. Hyndman and G. F.Origlio, J . AppZ. Phys., 1960, 31, 1849; G. Farrow, J. McIntosh, and I. M. Ward,Makromol. Chem., 1960, 38, 147.134 H. Leaderman, A. V. Tobolsky, and J. D. Ferry in “ Rheology, its theory andapplications,’’ Vol. 2, Ed. F. R. Eirich, Academic Press, New York, 1958; H. Leader-man, Amer. Rev. Chem. Phys., 1958, 9, 179.136 N. G. McCrum, Makromol. Chem., 1959, 34, 50; K. Illers and E. Jenckel, J .Polymer Sci., 1959, 41, 528.lS6 G. P. Mikhailov, Makromol. Chem., 1960, 35, 26; G. P. Mikhailov, Vysokomol.Soedineniya, 1960, 2, 287, 302, 619, 1541, 1552; D. W. McCall and E. W. Anderson,J . Ckem. Phys.. 1960, 32, 237; S. Kurosaki and T. Furumaya, J . Polymer Sci., 1960,$3, 137.467.G. Allen, G. Gee, and D. Sims, to be published.1, 365.1529ALLEN AND JONES: PHYSlCAL PROPERTIES OF POLYMERS. 113One review 13' compares mechanical and nuclear magnetic resonmce datafor poly-ethylene, -propene, -but-l-ene, -styrene, -isobutene, -(vinyl chloride),-(methyl methacrylate), -tetrduoroethylene, and nylon-6 and -66. In poly-ethylene, for example, the existence of three transitions is ascribed tocrystal disordering and the motion of (a) large and (b) smaller chain segmentsin amorphous regions. Polymers containing large substituents usuallyshow at least two transitions, one associated with segmental motion of themain ckain and the other with the mobility of the side chains. Stressrelaxation and creep measurements 2~134 also yield information about themotion of the main chains; less widely used techniques include measure-ments of velocity of sound139 and also the application of piezo-electriccrystals.lM A few studies of the effect of pressure on relaxation processeshave been rep0rted.~m~1*1Viscosity measurements are complicated by non-Newtonian behaviourand extreme sensitivity to rate of shear.142 The concept of segmental flowis supported by the fact that activation energies tend to limiting values asthe molecular weight increases, e.g.Eats (kcal.) T ("c) Ref.Pol yet h ylene (linear) ..................... 7.5 150-250 143Polystyrene ................................. 2 1-25 200-250 147Polytetrafluoroethylene .................. 25 < 365 148Pol ydimeth yIsiloxane ..................... 4.0 - 40-60 149,, (branched) .................. 12-15 8 143, 144Polyisobutene .............................. 12-16 0-120 145, 146Pressure coefficients of viscosity have been reported for polymers of lowmolecular ~ e i g h t . l ~ J ~ OChemical structure and polymer properties. As in the case of simplemolecules, molecular cohesion influences physical properties (Gee 112) andevidently obeys similar structural laws.122 In polymers, chain configurationis an additional factor. Dynamic properties depend on the rate of inter-change between various configurations (i.e. chain flexibility), but moleculartheories 151 are handicapped by lack of information relating to internalJ. A. Sauer and A. E. Woodward, Rev. Mod. Phys., 1960, 32, 88.138 E. W. Hoff, D. W. Robinson, and A. H. Willbourn, J . Polymer Sci., 1955, 18,la* M. Baccaredda and E. Butta, J . Polymer Sci., 1960, 44, 421.140 A. J. Barlow and J. Lamb, Proc. Roy. Soc., 1959, A , 253, 62.141 L. A. Igonin, Y u . V. Ovchinnikov, and V. A. Kargin, Doklady Akad. NuukS.S.S.R., 1959, 128, 127; A. W. Nolle and J. J. Billings, J . Chem. Phys., 1959, 30, 84;A. W. Nolle, J . Afifil. Phys., 1960, 31, 1694.142 A. Bondi, T. G. Fox, S. Gratch, and S. Loshack in " Rheology, its theory andapplication," Vol. 1, Ed. F. R. Eirich, Academic Press, New York, 1956.143 L. H. Tung, Amer. Chem. SOC., Cleveland Meeting, 1960, 1, 14,14* S. L. Aggarwal, L. Marker, and M. J. Carrano, J . Appl. PoZymer Sci., 1960, 3, 78;R. S. Porter and J. F. Johnson, ibid., p. 194.145 G. Allen, G. Gee, H. A. Lanceley, D. Mangaraj, J . Polymer Sci., 1959, 34, 349.146 R. S. Porter and J. F. Johnson, Amer. Chem. SOC., Cleveland Meeting, 1960,1, 301.14' J. F. Rudd, J . Polymer Sci., 1960, 44, 459.148 L. C. Case, J . AppZ. Polymer Sci., 1960, 3, 254.149 G. J. Wilson, Ph.D. thesis, Manchester University, 1960.150 H. Singh and A. W. Nolle, J . AppZ. Phys., 1959, 30, 337; Amer. SOC. Mech. Eng.,151 A. V. Tobolsky, ref. 2, ch. 4, p. 16G.161; K. M. Sinnott, ibid., 1960, 42, 3.Pressure-Viscosity Report, 1953114 GENERAL AND PHYSICAL CHEMISTRY.rotation about chemical bonds. Indeed, experimental estimation of chainflexibility poses a difficult problem.l12 Equilibrium properties are deter-mined by free-energy differences between initial and final configurationalstates. The kinetic theory only considers a highly idealized model but amore sophisticated treatment should take into account the structure of themolecular chains.G. A.M. N. J.G. ALLEN.A. BEWICK.A. D. BUCKINGHAM.M. FLEISCHMANN.H. M. FREY.M. N. JONES.J. W. LINNETT.I. M. MILLS.J. E. PRUE.H. A. SKINNER.M. C. R. SYMONS

ISSN:0365-6217    

DOI:10.1039/AR9605700007

出版商:RSC    

年代:1960

数据来源: RSC

摘要:

INORGANIC CHEMISTRY1. INTRODUCTIONTHE year 1960 has been characterised by steady progress rather than byspectacular advances in inorganic chemistry : compounds of boron, silicon,and phosphorus continue to excite particular interest, and a large numberof papers on complexes of transition metals and organic ligands have againbeen published. This Report follows the now well-established pattern ofproviding general coverage rather than a collection of reviews; in the border-land field of organic derivatives of metallic and non-metallic elements,however, it has been possible to mention only some of the many new com-pounds which have been described.Two general textbooks of inorganic chemistry to honours-degree stan-dard l p 2 have made welcome appearances during the year, and a new editionof “ Emelkus and Anderson ” has been published. A third edition of“The Nature of the Chemical Bond ” gives an up-to-date but one-sidedaccount of valence theory and inorganic structures.Several other booksare mentioned in later sections.The publication of Uspekhti Khimii in an English translation shouldhelp greatly in making chemists familiar with Russian work. Amonggeneral reviews which have appeared during the year are those on organo-metallic compounds,6 metal alkoxides,’ inorganic stereochemistry,s theinfrared spectra of inorganic compounds in the caesium bromide regionDgthe uses of non-aqueous solvents in preparative inorganic chemistry,1° andliquid-liquid extraction of inorganic compounds.11 The reasons for, andconsequences of, the adoption of 12C = 12 as the standard for atomic weightshave been summarised.12New clathrate compounds of argon, krypton, or xenon, an organic com-pound (acetone, methylene dichloride, chloroform, or carbon tetrachloride)J.Kleinberg, W. J. Argersinger, jun., and E. Griswold, “ Inorganic Chemistry,”D. C. Heath & Co., Boston, U.S.A., 1960.a R. B. Heslop and P. L. Robinson, “ ]Fporganic Chemistry,” Elsevier, 1960. * H. J. Emeldus and J. S. Anderson, Modern Aspects of Inorganic Chemistry,”Routledge and Kegan Paul, London, 1960.L. C. Pauling, “ The Nature of the Chemical Bond,” Cornell Univ. Press, 3rd edn.,1960.Russian Chemical Reviews, The Chemical Society, London; the translated journala t present begins with the January 1960 issue of the original.* J.Eisch and H. Gilman, Adv. Inorg. Chem. Radiochem., 1960, 2, 61; G. E. Coates,I ‘ Organometallic Compounds,” Methuen, 2nd edn., 1960.D. C. Bradley, Progr. Inorg. Chem., 1960, 2, 303.J. D. Dunitz and L. E. Orgel:[Adv. Inorg. Chem. Radiochem., 1960, 2, 1; L. E.Orgel, J., 1959, 3815; L. E. Orgel, An Introduction to Transition-Metal Chemistry,”Methuen, London, 1960.F. A. Miller, G. L. Carlson, F. F. Bentley, and W. H. Jones, Spectrochim. Acta,1960, 16, 135.lo C. C. Addison, Roy. Inst. Chem. Lectures, Monographs, Reports, 1960, No. 2.l1 F. S. Martin and R. J. W. Holt, Quart. Rev., 1959, 13, 327; R. M. Diamond andT). G. Tuck, Progr. Inorg. Chem., 1960, 2, 109.l2 D. H. Whiffen, Proc. Chem. Soc., 1960, 971 1s INORGANIC CHEMISTRY.and ice, having the composition A,2B,17H20 (where A is the organic com-ponent and B the inert gas), have been prepared.l3 Ammonia and benzeneform clathrates with complex cyanides of formula MNi(CN), (where M = Cu,Cd, or Zn) analogous to the well-known compound formed with nickelcyanide.14 Many hydrates of tetra-t-butyl- and -isopentyl-ammonium saltshave been made; it seems likely that these are clathrates in which ionsoccupy cavities in the structure of ice.l5D.W. A. S.A. G. S.2. TYPICAL ELEMENTSHydrogen.-A valuable book l6 gives a general account of hydrogenbonding and is especially noteworthy for the quantity of physical data whichit contains. A neutron-diffraction study 17 of potassium hydrogen bis-phenylacetate (in which an O-H 0 bond of length 2-55 A has previouslybeen shown to be present) confirms that the hydrogen atom is midwaybetween the oxygen atoms.A short hydrogen bond (length 2.48 A) is foundin rubidium hydrogen citrate.18 The infrared and proton magnetic reson-ance spectra of many substances containing very short hydrogen bondshave been discussed in an important paper by Blinc and Hadii.lg Thesubstances fall into two groups. Members of the first group (which includesmetal hydrogen phosphates, arsenates, periodates, phthalates, and $-nitro-benzoates) have two O-H stretching bands, separated by 300-500 cm.-l,in the region 1900-3000 cm.-l; the proton resonance signals are strong andnarrow at room temperature and slightly broader at -180".Compoundsof the second group (to which belong potassium hydrogen bisphenylacetate,bisbenzoate, and maleate, and sodium sesquicarbonate) are characterisedby the absence of 0-H bond stretching frequencies in the region above1800 cm.-l; the proton resonance signals are narrow and weak or very weakat room temperature, and remain essentially unchanged at low temper-atures. These data are interpreted in terms of a potential function forproton motion having two potential-energy minima separated by a barrierwhich is small enough to allow tunnelling and subsequent splitting of vibra-tional levels in the first group, and is vanishingly small in the second group.In the latter, the hydrogen bond approaches the symmetrical configuration(the extreme case is potassium hydrogen maleate): the O-H stretchingfrequency becomes vanishingly small and the characteristic property of thevibration is lost owing to strong interaction with other modes; as there isno more large proton motion the relaxation time becomes long and theproton resonance signal is very weak.Data for nickel dimethylglyoxime,in which an O-H*..O bond of length 2-48w has been reported, are,18 J. G. Waller, Nutuve, 1960, 186, 429.l4 R. Baur and G. Schwarzenbach, HeZv. Chim. Actu, 1960, 45, 842.15 R. McMullan and G. A. Jeffrey, J . C h f y Phys., 1969, 31, 1231.G. C. Pimental and A. L. McClelland,17 G. E. Bacon and N. A. Curry, Actu Cvysf., 1960,18, 717.C. E. Nordman, A. S. Weldon, and A. L. Patterson, Actu Ctyst., 1960, 13, 414.1s R.Blinc and D. Hadii, SpectrocMm. Actu, 1960, 16, 862.The Hydrogen Bond," W. H. Freeman &Co., San Francisco and London, 1960SHARPE TYPICAL ELEMENTS. 117unfortunately, not adequate to show whether the hydrogen bond in thiscompound is symmetrical.The catalytic activation of hydrogen by metal salts has been furtherexamined: for copper carboxylates, hydrocarbons or acids being used assolvents, the reactions are autocatalytic, showing that cuprous as well ascupric compounds are effective, The influence of the polarity of the solventand the nature of the anion present have also been examined.20Reviews of the role of the proton in chemistry,21 and of the propertiesand structures of metal (especially transition-metal) hydrides, have beenpublished.22Group I.-An electron-diffraction study 23 of lithium chloride vapourshows the presence of planar diamond-shaped dimers with Li-Cl= 2.23,C1-Cl = 3-81 A, and LClLiCl= 108".The presence of rubidium chlorideresults in a substantial lower'ing of the CsCl ---t NaCl structure transitiontemperature for czsium chloride, and even at room temperature up to 30%of caesium chloride may remain in solid solution in rubidium chloride.=The nature of colour centres in alkali-metal halides has been discussed.25No solid polybromides are formed in the systems MBr-Br,-H,O if M = Lior Na.26Potassium and the sodium-potassium eutectic are slightly soluble (upto lo4 g.-atom/l.) in many ethers, giving unstable blue solutions similar tothe well-known blue solutions of alkali metals in ammonia and amines; thedissolving powers of ethers depend on the number of oxygen atoms present,the size of the ring if a chelated solvate of a cation is presumed to be formed,and steric factors near the ethereal oxygen atoms2' The absorption spectraof dilute solutions of sodium and potassium in liquid ammonia have beenstudied as functions of concentration and temperature.The shapes of theabsorption curves were found to be identical for the two metals, and wereindependent of concentrations; increase in temperature shifts the curvestowards lower energies. These results indicate that the absorption processin the near infrared region (6800 cm.-l) involves the excitation of an electronin a cavity to a higher energy level, and that this process is the same for bothmetals.2s Electrolysis of the sodamine-potassamide eutectic yields ammoniaand nitrogen at the anode; evidence has also been obtained for the form-ation of traces of hydra~ine.~~Potassium hydroxide at ordinary temperatures has a monoclinic struc-ture in which each potassium atom is surrounded by a distorted octahedron ofoxygen atoms; the hydroxyl groups form a zizag chain with O-H 0 =2o A. J.Chalk and J. Halpern, J . Amer. Chem. Soc., 1959, 81, 5846, 5862; A. J.Chalk, J. Halpem:, and A. C. Harkness, ibid., p. 6854.The Proton in Chemistry," Methuen, London, 1959.22 G. G. Libowitz, J , Nuclear Materials, 1960, 2, 1.23 S. H. Bauer, T. Ino, and R. F. Porter, J . Chem. Phys., 1960, 33, 685.24 L.J. Wood, C. Sweeney, and M. T. Derbes, J . Amer. Chem. SOL, 1959, 81, 6148.25 M. C. R. Symons and W. T. Doyle, Quart. Rev., 1960, 14, 62.26 G. H. Cheeseman and E. K. Nunn, J., 1960, 3684.J. L. Down, J. Lewis, B. Moore, and G. Wilkinson, J., 1959, 3767; concerningthe nature of these solutions, see also F. S. Dainton, D. M. Wiles, and A. N. Wright,J., 1960, 4283.R. P. Bell,28 R. C. Douthit and J. L. Dye, J . Amer. Chem. Soc., 1960, 82, 4472.M. H. MacDonald and R. D. Hill, J . Inorg. Nuclear Chm., 1960,15, 105118 INORGANIC CHEMISTRY.3-35 A, the bond being linear or very nearly so. The breaking of the hydro-gen bonds results in the formation of the cubic high-temperature form.30Group II.-The reaction Be2+ (melt) + Be ==+ 2Be+ (melt) has beenstudied for beryllium halides in fused alkali-metal halides at various tem-peratures; addition of fluoride ion displaces the equilibrium towards the leftowing to the formation of the stable BeF,2- complex ion.31 Thermal de-composition of ammonium fluoroberyllate takes place in the followingstages : 3,(NH,),BeF, - NH,BeF, ____t NH,Be,F, ~- BeF,There is no exchange of beryllium between diphenylberyllium andberyllium bromide in ethers, showing that the species PhBeBr is not formed(this result is the same as that obtained in the analogous system involvingmagnesium compounds).Formation of Grignard reagents is catalysed byalkoxides of alkali metals, magnesium, or aluminium. Organocalciumhalides have been prepared in ethereal solution from calcium metal andalkyl halides, the calcium being activated by heating it at 150" in argon witha little mercury; their reactions resemble those of the Grignard reagentsMGroup III.--Borort.Recent advances in boron chemistry have been thesubject of a monograph; 35 more specialised articles have dealt with boronhydride~,~~ the allotropy of boron,37 the fluoroboric acids and their deriva-tives,% and bora~oles.~~The use of diborane for the reduction of organic compounds has beenextensively reviewed, and differences between its action and that of theborohydride ion have been noted. These probably originate in the fact thatthe ion attacks as a nucleophilic reagent, but diborane, being a Lewis acid,is an electrophilic entity.40 Diborane reacts with ethylenediamine to forma compound for which the structure H,B*NH,-CH,*CH,*NH,*BH, is sug-gested (though formulation as a borohydride is not excluded) ; this substance,a stable white solid, is a selective reducing agent resembling sodium boro-hydride.41 Some other reactions of diborane have been studied.Methyland ethyl cyanides form compounds of formula RCN,BH3 which dissociatereversibly at low temperatures and decompose at room temperature, formingN'N"N"'-trialkylborazoles. Vinyl and phenyl cyanides form less stableadducts. Diborane also reacts with cyanogen and with hydrogen cyanide,30 J. A. Ibers, J. Kumamoto, and R. G. Snyder, J . Chem. Phys., 1960,53, 1164, 1171.s1 M. V. Smirnov and N. Ya. Chukreev, Zhur. neorg. Khim., 1959, 4, 2536 [1168].*8, 0.N. Breusov, M. N. Vagurtova, A. V. Novoselova, and Y . P. Simanov, Zhur.38 R. E. Dessy, J . Amer. Chem. SOC., 1960, 82, 1680.84 E. J. Blues and D. Bryce-Smith, Chem. and Ind., 1960, 1633; D. Bryce-Smith85 H. G. Heal, Roy. Inst. Chem. Lectures, Monographs, Reeorfs, 1960, No. 1.86 A. B. Burg, Angew. Chem., 1960, 72, 183; F. G. A. Stone, Adv. Inorg. Chem.37 J. L. Hoard and A. E. Newkirk, J . Amer. Chem. SOL, 1960, 82, 70.38 D. W. A. Sharp, Adv. Fluorine Chem., 1960, 1, 68.3s J. C. Sheldon and B. C . Smith, Quart. Rev., 1960, 14, 200.40 H. C . Brown and B. C. Subba Rao, J . Amer. Chem. SOC., 1960, 82, 681.41 H. C. Kelley and J. 0. Edwards, J . Amer. Chem. SOC., 1960, 82, 4842.* Figures in brackets refer to the English translation.neorg.Khim., 1959, 4, 2213 [1008].and A. C. Skinner, ibid., p. 1106.Radiochem., 1960, 2, 279SHARPE : TYPICAL ELEMENTS. 119but the products of these reactions have not been ~haracterised.~~ Tetra-methylhydrazine and tetramethyldiphosphine form compounds M,Me4,2BH3 ;these decompose when heated according to the equation 43M,Me4,2BH, -+ 2Me2M,BH2 + H,Pure diborane reacts only very slowly with olefins, but in the presence oftraces of ethers rapid addition to give trialkylboranes takes place at roomtemperature :6RCH=CH2 + B2H, ___+c 2 (RCH2CH2),BThese compounds, which can be converted into alcohols by the action ofalkaline hydrogen peroxide, can also be obtained from olefins and sodiumborohydride, aluminium chloride and diethylene glycol dimethyl ether andby many variations of this method.44 Aluminium, hydrogen, alkyl halides,and boron trichloride also react giving alkylboranes : 85The reaction between the compound Me,N,BH, and aqueous hydro-chloric acid is of the first order with respect to both reactants, and is visual-ised as a displacement of borane by a proton, followed by rapid decom-position of the borane, or as a direct attack on the B-H bond by the reactionMe,N,BH, + H,O+ - Me,N*BH,+ + H2 4- HZ0followed by a rapid reaction of the ion formed.46 Several alkylamine-boranes, anHnN,BH3, have been made by the interaction of alkali oralkaline-earth metal borohydrides in ethers and alkylammonium salts ; thecompounds are monomeric in polar solvents but polymerise to variousextents in benzene.47 The corresponding B-monohalogeno-compounds areobtained by the action of hydrogen halides, halogens, or boron trihalides onN-alkylboranes, or by the interaction of tertiaxy amines and compounds ofmonochloroborane with ethers.@ The compound (H2N),P,BH3, formed bythe action of ammonia on the unstable phosphorus trifluoride-borane adduct,has been shown 4g to have an approximately tetrahedral configuration roundthe phosphorus atom, with P-N = 1.65 and P-B = 1.89 A.A phase study of the magnesium-boron system reveals the interestingfact that there is no compound Mg3B2, the expected derivative of borane;the only phase found is MgB2.50The mechanism of the interconversion of the boron hydrides has beenH.J. Emelbus and K. Wade, J., 1960, 2614.H.Noth, 2. Naturforsch., 1960, 15b, 327.44 H. C. Brown and B. C. Subba Rao, J. Amer. Chcm. SOL, 1960, 82, 6423, 6428;45 E. L. Muetterties, J. Amer. Chem. SOL, 1960, 82, 4163.46 G. E. Ryschkewitsch, J. Amer. Chem. SOC., 1960, 82, 3290.47 H. Noth and H. Beyer, Ber., 1960, 93, 928, 939.48 H. Noth and H. Beyer, Ber., 1960, 93, 2251.49 C. E. Nordman, Acta Cryst., 1960, 13, 535.5 O L. Y. Markovskii, G. V. Kaputovskaya, and Y. D. Kondrashev, Zhuv. neovg.H. C. Brown, I<. J. Murray, L. J. Murray, J. A. Snover, and G. Zweifel, ibid., p. 4233.Khim., 1959, 4, 1710 [771]120 INORGANIC CHEMISTRY.discussed, and the kinetics of the formation of the pentaborane B,Hl, fromtetraborane in the presence of diborane have been interpreted in terms of thereaction sequenceHBin which the first stage is rate-detem~ining.~~ A mass-spectrographic in-vestigation of the products of the action of an electric discharge on diboraneprovides evidence for the existence of a new hydride of probable formulaB,H12.52 The complex mixture resulting from the interaction of diboraneand ethylene has been shown by vapour-phase chromatography to contain,amongst other things, members of two homologous series , ethyl derivativesof B5H9 and B10H14; direct alkylation of these two hydrides has also beenstudied.63The structure of the compound formerly regarded as the diammoniateof diborane is now well established as [(H,N),NH,]+BH4-; the analogousderivative of tetraborane has the structure [(H,N],NH,]+B,H,-, the anionhaving the structure (1) :ester, of formula (MeO),B*CH,*CH,*B(OMe),,is produced.The sodium derivative of decarborane reactswith iodine in ethereal solution, forming ethoxy-51 R.Schaeffer, J . Inorg. Nuclear Chem., 1960, 15, 190; J. A. Dupont and R.52 S. G. Gibbins and I. Shapiro, J . Amer. Chem. SOC., 1960, 82, 2968.53 N. J. Blay, J. Williams, and R. L. Williams, J., 1960, 424; N. J, BIay, I. Dunstan,64 C. R. Peters and C. E. Nordman, J . Amer. Chem. SOC., 1960, 82, 5758.55 B. C. Harrison, I. J. Solomon, R. D. Hites, and M. J. Klein, J - Inorg. Nuclear56 M. F. Hawthorne and J. J. Miller, J . Amer. Chem. Sac., 1960, 82, 600.57 M, Hillman, J . Amer. Chem. SOC., 1960, 82, 1096; J . Inorg. Nuclear Chem., 1960,Schaeffer, ibid., p. 310.and R.L. Williams, J., 1960, 430.Chem., 1960, 14, 195.12, 383SHARPE TYPICAL ELEMENTS. 121BloH13- ion have been made from decaborane and tetra-alkylammoniumhydroxides in diethylene glycol dimethyl ether.68 Triethylamine and 2-iodo-decaborane in dry benzene at room temperature yield (Et,NH) +2B10H102-and a little (Et,NH) +2B12H122-; the latter compound is converted by potass-ium hydroxide into the salt K2B12Hl,. The infrared and nuclear magneticresonance spectra of the Bl2H12- ion are compatible with the predictedicosahedral stru~ture,5~ and further evidence for this structure has beenprovided by X-ray analysis.60Trimethylboron and potassium in liquid ammonia form potassium amino-trimethylboronate, K[H2NBMe,], which when heated loses methane, givinga polyanionic salt which yields hydrogen and methane on hydrolysis. Thesolid compound does not react with trimethylboron or diborane, but withdiborane in the presence of ether it gives a solid of composition KNH,B2H6which is actually a mixture of potassium borohydride and a polymericaminoborane-an example of the unsymmetrical fission of diborane.'jlOther recent papers describe the properties and reactions of alkylboranes,62their application in the preparation of alkylated mercury and lead com-pounds,@ dealkylations effected by carboxylic acids,64 and the reactions oftrimethylamine alkylboranes with olefins and thio1s.GNuclear magnetic resonance spectra of mixtures of boron halidesestablish the existence of the compound BBrClF.66 Boron trifluoridereacts with the compound Me,SnCF, in carbon tetrachloride, yielding thesalt Me,Sn+ CF,-BF,-, which is converted into the corresponding potassiumsalt by the action of aqueous potassium fluoride.67 Complex formationbetween boron trifluoride and ethers has been re-investigated, and the earlierresults of H.C. Brown and his collaborators have, in general, been con-firmed.68 In accordance with the previously established order of stabilitiesfor boron trihalide complexes, it has been shown that boron trichloride dis-places the trifluoride from its trimethylamine complex.69 Other complexesof boron halides which have been studied during the year include those withpyridine and ~iperidine,~~ nit rile^,^^ primary and tertiary aromatic arnine~,'~SOC., 1960, 82, 1825.M.F. Hawthorne, A. R. Pitochelli, R. D. Strahm, and J. J. Miller, J . Amer. Chem.69 A. R. Pitochelli and M. F. Hawthorne, J . Amer. Chem. SOC., 1960, 82, 3228.6o J. A. Wunderlich and W. N. Lipscomb, J . Amer. Chem. SOC., 1960, 82, 4427.6L A. K. Holliday and N. R. Thompson, J., 1960, 2695.62 R. Koster, Angew. Chem., 1960, 72, 626; L. Rosenblum, J. Org. Chew, 1960,64 J. Crighton, A. K. Holliday, A. G. Massey, and N. R. Thompson, Clzem. and Ind.,65 M. I;. Hawthorne, J . Amer. Chem. SOC., 1960, 82, 748.66 T. D. Coyle and F. G. A. Stone, J. Chem. Phys., 1960, 32, 1892.67 R. D. Chambers, H. C . Clark, and C . J. Willis, Proc. Chem. SOC., 1960, 114;D. E. McLaughlin and M. Jamres, J. Amer. Chem. Soc., 1960, 82, 5618; D. E.W.Dutton, W. G. Paterson, and M. Onyszchuk, Proc. Chem. SOL, 1960, 149.70 N. N. Greenwood and K. Wade, J., 1960, 1130; N. N. Greenwood and P. G.71 W. Gerrard, M. F. Lappert, and J. W. Wallis, J., 1960, 2178; W. Gerrard, M. F.7* W. Gerrard and E. F. Mooney, J., 1960, 4028; R. D. W. Kemmitt, R. H. Nuttall,25, 1652.J. B. Honeycott and J. M. Riddle, J . Amer. Chem. SOL, 1960, 82, 3051.1960, 347.J . Amer. Chem. SOC., 1960, 82, 5298.McLaughlin, M. Jamres, and S. Searles, ibid., p. 5621.Perkins, J., 1960, 1141, 1145.Lappert, H. F'yszora, and J. W. Wallis, J., 1960, 2182.and D. W. A. Sharp, J., 1960, 46122 INORGANIC CHEMISTRYand phosphorus o~ychloride.~~ The last group of compounds have struc-tures of the type Cl,PO -+ BX,. Contrary to earlier reports, '' alkoxy-difluoroboranes" of composition ROBF, are found to be complexes oftrialkyl borates and boron trifl~oride,'~ and tetramethylammonium halidesare shown to yield only tetrafluoroborates when treated with hydroxy- ormethoxy-trifluoroboric acid.75Boron trichloride reacts with triphenyl phosphite, even at --80", accord-ing to the scheme 76Tetrachloroborates of potassium, czesium, and ammonium have been madeby cold milling of the alkali-metal chloride and boron trichloride at roomtemperature ; tetrabromo- and tetraiodo-borates of large organic cationshave been obtained from the constituent halides in liquid hydrogen halidesas solvents.77 Further work on the chemistry of diboron tetrachloride hasbeen rep~rted.'~ The compound adds across olefinic double bonds; theproduct which is obtained from ethylene, Cl,B*CH,*CH,*BCl,, decomposesat 500" yielding hydrogen, methane, ethane, boron trichloride, and a poly-meric monochloride.It forms a 1 : 2 adduct with trimethylamine whichreacts with hydrogen chloride to form a salt :(PhO),P + BCI, - (PhO),PCI + PhOBCI,Me,N* BCI ,*CH ,-CH ,* BC I ,*N Me, + 2H C I - (M e,N H) ,+ (CI,BCH ,*C H,*BC1J2-Hydrolysis of the ethylene " adduct " yields the compound B,(OH),,C,H,which loses water when heated, forming a glass of composition B,0,,C2H4.When diboron tetrachloride reacts with dimethylaminodimethylborine thepredominant reaction is attachment of two molecules of the latter compoundfollowed by elimination of dimethylboron chloride and formation of a non-volatile, presumably polymeric, dimethylamino-derivative : 79ClzB- BCI,___t 2Me2BCI + "'$-r' t t MezN NMe,Me,B*NMe, NMe,-BMe,This process would involve donation from the lone pairs of the nitrogenatoms to each boron atom; possible evidence for x-donation as a side reactionis provided by the isolation of some dimethylaminoboron dichloride and thepolymeric monochloride :C1,B-BCI,-fMe, B=N Me, - Me,BCI + BCI + Me,N*BCI,73 T.C. Waddington and F. Klanberg, J., 1960, 2339.74 P. A. McCusker and S. M. L. Kilzer, J . Amer. Chem. Soc., 1960, 82, 372.75 K. C . Moss and D. W. A. Sharp, J . Inorg. Nuclear Chem., 1960, 13, 328.713 W. Gerrard and M. Lindsay, Chem. and Ind., 1960, 152.77 W. Kynaston, B. E. Larcombe, and H. S.Turner, J., 1960, 1772; T. C. Wadding-ton and J. A. White, Proc. Chem. SOC., 1960, 85, 315.r8 P. Ceron, A. Finch, J. Frey, J. Kerrigan, T. Parsons, G. Urry, and H. I. Schlesin-ger, J . Amer. Chem. SOC., 1959, 81, 6368; A. K. Holliday and A. G. Massey, J.,43, 2075.79 A. K. Holliday, A. G. Massey, and F. B. Taylor, Proc. Chem. Sot., 1960, 369SHARPE : TYPICAL ELEMENTS. 123Several substituted boron isocyanates and isothiocyanates have beenmade from the appropriate halogen compounds and alkali metal, silver, orlead salts.80 A polymer of formula (PhB). (n = 9 or 10) is obtained bythe action of sodium on phenylboron dichloride in toluene; the productcombines with ammonia, forming a polymer of composition PhB,NH,, andis decomposed by water : 81PhB + 2H2O ___jc PhB(OH), + HzA new preparation of borazole, from sodium borohydride and ammoniumchloride in triethylene glycol dimethyl ether, has been described; N-tri-substituted borazoles may be made by analogous reactions, or by the actionof sodium borohydride on the N-substituted tri-B-chloroborazoles whichresult from the interaction of boron trichloride and primary amines inchlorobenzene.82 Solid borazole has been shown by X-ray powder photo-graphy to be isomorphous with solid benzene.83 Tri-B-organosilyl- andtri-B-organosiloxy-N-alkylborazoles have been made from the B-chloro-compounds and appropriate alkali-metal derivatives of silanes or silanols.84The compounds (R,P*BH,), where R = Me,Et, or R, = -[CH&- have beenprepared: the methyl compound, for example, results from the interactionof Me,POCl and NaBH, in diethylene glycol dimethyl ether or by thermaldecomposition of the compound Me,NPMe,,BH,.=At high temperatures the volatility of boric oxide is much increased bythe presence of water vapour; the principal species in the vapour is HBO,,in which the boron and both oxygen atoms are collinear.86 Dimethyl-borinic acid reacts with potassium hydroxide and ammonia to form thecompounds K [Me,B (OH) and Me,BOH,NH,, respectively ; with potassiumin liquid ammonia it gives trimethylboron and potassium methylboronate,the latter compound being stabilised by addition of two molecules of di-methylborinic acid.87 When dkali-metal borates are dissolved in methanol,salts containing the B(OMe),- ion are formed.88 The B,O,- anion in KB,O,has an interesting structure in which each oxygen atom of a centralBO, tetrahedron is shared with a planar BO, triangle; the B-O bond lengthsin the tetrahedron and triangle are 1.45 and 1.34A, respecti~ely.8~ Whatmay prove to be a new lower oxyacid of boron, a white solid of empiricalformula BOH, is formed (together with nitrogen, hydrogen, and higherhydrides) in the reaction between diborane and oxygen atoms produced bythe photosensitised decomposition of nitrous8o J.Goubeau and H. Grabner, Ber., 1960, 93, 1379; M. F. Lappert and H. Pyszora,Proc. Chem. SOG., 1960, 350.81 W. Kuchen and R. D. Brinkmann, Angew. Chem., 1960, 72, 564.8z D. T. Haworth and L. F. Hohnstedt, Chem. and Ind., 1960, 559; J .Amer. Chem.SOC., 1960, 82, 89, 3860.83 M. T. Falqui, M. A. Rollier, and M. Secci, Ann. Chim. (IiaZy), 1960, 50, 190.84 A. H. Cowley, H. H. Sisler, and G. E. Ryschkewitsch, J . Amer. Chem. Suc., 1960,82, 501 ; D. Seyferth and H. P. Kogler, J . Inorg. NucZear Chem., 1960,15, 99.85 A. B. Burg and P. J. Slota, J . Amer. Chem. Soc., 1960, 82, 2145, 2148.86 D. White, D. E. Mann, P. M. Walsh, and A. Sommer, J . Chem. Phys., 1960, 32,488. *' J. Goubeau and J. W. Ewers, 2. anorg. Chem., 1960, 304, 230.88 H.-A. Lehmsnn and D. Tiess, 2. anorg. Chem., 1960, 304, 89.8s J. Krogh-Moe, Arkiv Kemi, 1959, 14, 439.eo F. P. Fehlner and R. L. Strong, J . Phys. Chem., 1960, 64, 1522124 INORGANIC CHEMISTRY.The main product of the action of boron on silicon at 1370" is B,Si, whichis extremely resistant to oxidation owing to formation of a protective B-O-Sicoating; 91 the cubic phosphide BP and arsenide BAS, made from the elementsat 1OOO", are also extremely inert.g2Alzcminhm. A preformed aluminium foil undergoes only a surfacereaction with atomic hydrogen, but a hydride of undetermined formula isproduced if the metal is evaporated in atomic hydrogen.93 The NNN'N-tetramethylethylenedamine adduct of aluminium hydride may be obtainedby the action of the diamine dihydrochloride on lithium aluminium hydridein excess of the amine as solvent, or by displacement of trimethylamine fromthe compound Me,N,AlH,.It is stable at 133" during 24 hr. and is dimeric;the structure (3) is suggested: 94Me Me Me M eMe Me Me M eMany other tertiary amine complexes have been made by analogous methods ;under similar conditions dialkylammonium halides give products of empiri-cal formula R2N*A1H2 which are associated and probably contain six-membered rings in which nitrogen and aluminium atoms occupy alternatepositions.95 A detailed study has been made of the optimum conditions €orthe preparation of lithium aluminium h ~ d r i d e , ~ ~ , and it has been shownthat this compound reacts with diphenylamine to form a substitutedhydride of formula Li[Al(NPh,),H] ,Et20.97Aluminium chloride reacts with the sulphide in a sealed tube at 350" togive the thiochloride AlSC1, which is converted by ammonia into the com-pound AlSN H2,2NH3 .98 In the system AlCl,-HCl-t oluene, compoundshaving molar ratios 2 : 1 : 6, 2 : 1 : 4, 1 : 1 : 2, and 1 : 1 : 3 exist; thepressure of hydrogen chloride above the system is a minimum whenthe AlCl, : HC1 ratio is 2 : 1; conductivity data for the analogoussystem with mesitylene suggest that Al,Cl,- is the stable anion inthese systems.gg When an aluminium chloride solution is treated with2.5 equivalents of sodium hydroxide and sodium selenate is added, aprecipitate of composition N%O, 13A120,,8Se0,,xH,0 (x is about 74} isformed; a preliminary X-ray study shows this to contain the polymericcation [All3O4(0H),(H20),j7f, in which a NO, tetrahedron is surrounded91 E.Colton, J . Amer. Ckem. SOC., 1960, 82, 1002.Q2 F. V. Williams and R. A. Ruehrwen, J . Amer. Chem. SOC., 1960, 82, 1330.93 B.Siegel, J. Amer. Chem. SOC., 1960, 82, 1536.94 J . M. Davidson and T. Wartik, J. Amer. Chem. SOC., 1960, 82, 5506.95 J. K. Ruff and M. F. Hawthorne, J. Amer. Chem. SOC., 1960, 82, 2141.96 V. I. Mikheeva, M. S. Selivokhina, and V. V. Leonova, Zhur. neorg. Khim., 1959,97 P. Longi, G. Mazzanti, and F. Bernardini, GuzzeZla, 1960, 90, 180.98 P. Hagenmuller and J . Rouxel, Com$t. r#nd., 1960, 250, 1859.B9 K. H. Leiser and C. E. Pfiuger, Ber., 1960, 98, 176, 181.4, 2436, 2705 L1119, 12603SHARPE : TYPICAL ELEMENTS. 125by twelve NO, octahedra sharing edges.100 The compound AlPS, has achain structure like that of silicon disulphide.lo1Much further work on aluminium alkyls has been published. Thetrialkyls react with aluminium and hydrogen according to the scheme lo22R3AI + Al + ;Ha ____) 3R,AIHSince the products add olefins to form trialkyls this is, in effect, a catalyticmethod for the preparation of these substances.Many complexes of thealkyls with alkali-metal halides or cyanides have been described,lW andreactions of the alkyls with organic compounds have been discussed indetail.lM Aluminium and boron alkyls rapidly exchange alkyl groups atroom temperature.105Gallium, indium, artd thallium. The preparation and properties ofacetone, pyridine, and piperidine complexes of gallium halides have beendescribed.lo6 p-Ga,O, has been found to contain both tetrahedrally andoctahedrdly co-ordinated gallium, Ga-0 distances being 1-83 and 2.00 A,respectively .Io7Indium chloride, bromide, and iodide combine with ethers, usually form-ing 1 : 2 complexes ; the slowness of dissolution of the trichloride is attributedto a substantial activation energy for the conversion of the essentially ioniclayer lattice into a molecular complex.lo8 Trimethylindium reacts withphosphine at low temperatures to form a 1 : 1 adduct which decomposes at-78" into the reactants and a compound [-InMe*PH,-1,; the latter com-pound is also formed when phosphine is passed into a solution of trimethyl-indium in benzene.logThe Me,Tl+ ion in aqueous solution contains a linear C-T1-C skeleton; 110the compounds of formula MIT10, have been shown to be mixed oxides, likethe " ferrites." 111Group IV.-Carbon.The intercalation compounds of graphite have beenreviewed.l12 Contrary to earlier reports, solid hydrogen cyanide is tetra-meric and consists of diaminomaleonitrile molecules.113 Sodium cyanate isloo G.Johansson, Ada Chem. Sand., 1960, 14, 771.lol A. Weiss and H. Schafer, Naturwiss., 1960, 47, 496.loa K. Ziegler, H.-G. Gellert, H. Lehmkuhl, W. Pfohl, and K. Zosel, AnnuZen,1960, 629, 1.lo3 K. Ziegler, R. Koster, H. Lehmkuhl, and K. Reinert, Annalen, 1960, 629, 33.lo4 K. Ziegler, H.-G. Gellert, K. Zosel, E. Holzkamp, J. Schneider, M. Soll, andW.-R. Kroll, AnnuZen, 1960, 629, 121; K. Ziegler, H. G. Gellert, E. Holzkamp, G. Wilke,E. W. Duck, and W.-R. Kroll, ibid., p. 172; G. Wilke and H. Miiller, ibid., p. 222;K. Ziegler, F. Krupp, and K. Zosel, ibid., p . 241; K . Ziegler, F.Krupp, K. Weyer,and W. Larbig, ibid., p. 261.loS R. Kijster and B. Giinter, Annalen, 1960, 629, 89.lo8 N. N. Greenwood and I. J. Worrall, J., 1960, 353; N. N. Greenwood and P. G.Perkins, J., 1960, 356.lo7 S. Geller, J . Chem. Phys., 1960, 33, 676.lo* F. Fairbrother, N. Flitcroft, and H. Prophet, J . Less-Common Metals, 1960, 2, 49.lo@ R. Didchenko, J. E. Alix, and R. H. Toeniskoetter, J . Inorg. Nuclew Chem.,111 R. Hoppe and G. Werding, Naturwiss., 1960, 47, 203.llS R. C. Croft, Quart. Rev., 1960, 14, 1.1960, 14, 35.P. L. Goggin and L. A. Woodward, Trans. Faruday Soc., 1960, 66, 1691.B. R. Penfold and W. M. Lipscomb, Tetrahedron Letters, 1960, No. 6, 17; D. A.Long, W. 0. George, and A. E. Williams, PYOC. Chem. SOL, 1960, 285126 INORGANIC CHEMISTRY,obtained in 90% yield by the action of sodium dispersions on urea.114Cyanogen fluoride has been obtained pure by the pyrolysis of cyanuricfluoride in a stream of nitrogen at 1300'/50 mm.; it can be stored in stainlesssteel if cooled in solid carbon dioxide, but it polymerises rapidly at roomtemperature.l16 Oxygen, carbon monoxide, and fluorine interact slowly at0--50", forming a compound C,F204 (b. p. 16') for which the structureF*CO*O* 0-CO *F is suggested. 116 Dichlorocarbene (carbon dichloride) hasbeen made by the action of active carbon on carbon tetrachloride at 1300";it has m. p. -114', b. p. -20", oxidises to carbonyl chloride in air, and isconverted into hexachloroethane by chlorine.l17 The polymer obtained bysubjecting carbon disulphide to very high pressures has the structureSilicon. Technical details of a preparation of a mixture of silanes frommagnesium silicide and dilute sulphuric acid and new techniques for themanipulation of these substances outside a closed apparatus (e.g., by theuse of injection syringes) have been described.llg The product formed bythe action of silyl iodide on silver cyanide is the normal cyanide, though theisothiocyanate is formed from silver thiocyanate ; silyl and trimethylsilylcyanides react with boron halides to form silyl halides and solid polymers ofempirical formula BX2CN.120 Silyl iodide can be prepared by a routeavoiding silane if chlorophenylsilane is allowed to react in a sealed tubewith hydrogen iodide; silylene di-iodide can be made similarly from di-phenylsilane or by the action of liquid hydrogen iodide on iodophenylsilane ;the monoiodide forms a weak complex with ether and a strong one withtetrahydrofuran, but does not react with furan, thiophen, or dimethylsulphide.121 Disilane is converted into an iodide by hydrogen iodide andaluminium iodide at ordinary temperatures ; the compound is rapidlyhydrolysed to the ether (SiH3-SiH2),0 and hydrogen iodide.122 Silyltrifluoromethyl sulphide, SiH,*S*CF3, is obtained by interaction of silyliodide and the compound Hg(S*CF,),; it decomposes readily, forming silylfluoride and a product which appears to be the previously unknown thio-carbonyl fluoride, CSF,.123Tris(trimethylsily1)-amine and -phosphine have been prepared by thereactions[-c(:s) *S-],.118HN(SiMe,), + CISiMe, - N(SiMe,), + HCIand NaPH, + 3MesSiCI - P(SiMe& + NaCl + 2HCI114 D.0. McPree, E. B. Oldenburg, and J. A. Burns, jun., J . Inorg. NucZear Chem.,115 F. S . Fawcett and R. D. Lipscomb, J . Amer. Chem. SOL, 1960, 82, 1609.116 A. J. Arvia, P. J. Aymonino, C. H. Waldow, and H. J. Schumacher, Angew.117 M. Schmeisser and H. Schrbter, Angew. Chem., 1960, 72, 349.11* E. WhaIley, Canad. J . Chem., 1960, 38, 2105.11s F. FehCr, G. Kuhlbbrsch, and H. Luhleich, 2. anurg. Chem., 1960, 303, 283, 294.120 J. Sheridan and A. C. Turner, Proc. Cham. Soc., 1960, 21; N. Muller and R. C.Bracken, J . Chem. Phys., 1960,32, 1577; D. R. Jenkins, R. Kewley, and T. M. Sugden,Proc. Chem. Soc., 1960, 220; E.C. Evers, W. 0. Freitag, W. A. Kriner, A. G.MacDiarmid, and S. Sujishi, J . Inorg. Nuclear Chem., 1960,13, 239.121 B. J. Aylett and I. A. Ellis, J., 1960, 3415; G. Fritz and D. Kummer, 2. anorg.Chem., 1960, 306, 191; B. J. Aylett, J . Inorg. Nuclear Chem., 1960,15, 87.12z L. G. L. Ward and A. G. MacDiarmid, J . Amer. Chem. Soc., 1960, 83, 2151.1*3 A. J. Downs and E. A. V. Ebsworth, J., 1960, 3516.1960, 15, 287.Chem., 1960, 72, 169SHARPE : TYPICAL ELEMENTS. 127respectively; the Raman and infrared spectra of the former suggest that thenitrogen and silicon atoms are not completely coplanar.124 Tetrasilyl-hydrazine, which, like trisilylamine, has no donor properties, has a staggeredconfiguration.125 The shifts in the 0-H stretching frequencies of silanolsand alcohols on admixture with ether and mesitylene have been compared,and it is concluded that silanols are, in terms of hydrogen-bond formation,much the more strongly acidic; this provides further evidence for theexistence of x-bonding between silicon and oxygen.lZ6In the presence of trimethylamine, hexachlorodisilane disproportionates :5Si,CI, ___t 4SiC1, + Si,CIIIThe new chloride sublimes at, 125°/10-5 mm.and dissolves in ether but notin benzene or carbon tetrachloride.127 Silicon tetrabromide and tetraiodideboth form unstable complexes with diphenyl sulphoxide ; these decompose atroom temperature into silica and diphenylsulphur dihalides ; the corre-sponding reaction with silicon tetrachloride also gives oxychlorides ; thetetrafluoride does not react .12*A valuable book on organosilicon compounds has appeared; 129 recentadvances in this field include the preparation of organosilicon perchloratesand chromates,130 methylsilicon isocyanates,131 fully chlorinated s i l ~ x a n e s , ~ ~ and polfluoroalkyl polysiloxanes.l% The polymers [-CH,*SiCl,-], and(Ph,Si)4 have been isolated.l=A new silicon boride SiB, is formed from the elements or by fusingthe hexaboride with silicon; its structure resembles that of carbont etraboride .I35Dipyridinegermanium tetrachloride has atrans-octahedral structure.136 The hydrate of germanium monoxide is thehydroxide Ge(OH),.13' Dimethylgermanium oxide, Me2Ge0, is obtainedas a tetramer by hydrolysis of the dichloride followed by extraction withpetroleum.In aqueous solution it is present as the diol, and polymericand trimeric forms also exist. Diphenylgermanium oxide shows similarGermanium, tin, and lead.la4 J. Goubeau and J. Jimgniz-Barber&, 2. anorg. Chem., 1960, 303, 217; A. J.lS6 B. J. Aylett, J. R. Hall, D. C. McKean, R. Taylor, and L. A. Woodward, Specfro-Leffler and E. G. Teach, J . Amer. Chem. Soc., 1960, 82, 2710.chim. Acta, 1960, 16, 747.R. West and R. H. Baney, J . Amer. Chem. Soc., 1959, 81, 6145.A. Kaczmarczyk and G. Urry, J . Amer. Chem. Soc., 1960,82, 751.la* K. Issleib and M. Tzschach, 2. anorg. ChAm., 1960, 305, 198.leB C. Eaborn, " Organosilicon Compounds,lSo U. Wannagat, F. Brandmair, W. Liehr, and H. Niederpriim, 2. anorg. Chern.,1959, 502, 185; M.Schmidt and H. Schmidbauer, Ber., 1960, 93, 878; E. W. Abel,2. Naturfovsch., 1960, 15b, 57.131 J. Goubeau and D. Paulin, Ber., 1960, 93, 1111; J. Goubeau and E. Heubach,ibid., p. 1117.Is* G. D. Cooper and A. R. Gilbert, J . Amer. Chem. Soc., 1960, 82, 5042.133 R. N. Haszeldine, M. J. Newlands, and J. B. Plumb, Proc. Chem. Soc., 1960, 147.lSp G. Fritz, D. Habel, D. Kumrner, and G. Teichmann, 2. anorg. Chem., 1959,302, 60; H. Gilman, D. J. Peterson, A. W. Jarvie, and H. J. S. Winkler, J . Amer.Chem. Soc., 1960, 82, 2076.136 C. F. Cline and D. E. Sands, J . Amer. Chem. SOC., 1960, 82, 1002; C. Brossetand B. Magnusson, Nature, 1960,187, 54.136 R. Hulme, G. J. Leigh, and I. R. Beattie, J., 1960, 366.lS7 T. Dupuis, Rec. Trav. chim., 1960, 79, 518.Butterworths, London, 1960128 INORGANXC CHEMISTRYallotropy.138 A trifluoromethyl derivative, CF,GeI,, has been made from tri-fluoroiodomethane and germanous iodide.139 The mechanism of hydrolysisof phen ylgermanium and phenylsilicon halides in aqueous acetone andacetone-ether has been discussed; the germanium compound is hydrolysedmore slowly; if a quinquecovalent intermediate is formed in these reactionsit reaches its steady-state concentration well within 10" sec.140 Whereastrimethylgermanium iodide gives a mixture of cyanide and isocyanide ontreatment with silver cyanide, trimethyltin iodide appears to give only thenormal cyanide.141More perfluoroalkyl, and some perfluorovinyl, derivatives of tin havebeen prepared,142 and the organic chemistry of tin has been reviewed.143 Di-and tri-phenylstannanes react with vinyl and ally1 derivatives of silicon,germanium, tin, and lead to form organometallic compounds containing two orthree metal atoms.lU The unstable chlorostannane SnH,Cl is obtained fromstannane and hydrogen chloride under carefully controlled conditions.16 Thedi- and tri-methyltin cations in solid carboxylates have been shown by infra-red spectroscopy to be linear and planar, respectively; solid stannous chloridedihydrate contains pyramidal molecules of SnC1,H20 and lattice water.146The compounds K,HSnF, and K,HPbF8 have been shown to be latticeaggregates of K+, HF,-, and SnF62- or PbF,2- ions.147 Di- and tri-methyl-plumbanes have been obtained from the corresponding chlorides and lithiumaluminium hydride in ether at -100"; at room temperature they dis-proportionate to lead, tetramethyl-lead, and hydrogen.l& A detailed studyhas been made of the non-stoicheiometric oxides of lead.1d9Group V.-Nitrogen.Dinitrogen tetrafluoride is formed when fluorinereacts with ammonia in a copper tube, and can be made in good yield by theaction of the pure trifluoride on mercury at 320". Dinitrogen difluoride isalso formed in the first reaction and, as a minor product, in the electrolysisof molten ammonium hydrogen fluoride; it exists as two isomers, formerlybelieved to be cis- and the tmzs-form, but recently shown to be the trans-compound and F2N=N.1M Difluoramine results from the reduction of di-188 M.P. Brown and E. G. Rochow, J . Amer. Chem. Soc., 1960, 82, 4166; W. Met-lesics and H. Ziess, ibid., p. 3324.189 H. C. Clark and C. J. Willis, Proc. Chem. SOC., 1960, 282.140 J. R. Chipperfield and R. H. Prince, Proc. Chem. SOC., 1960, 385.141 D. Seyferth and N. Kahlen, J . Org. Chem., 1960, 25, 809.148 R. D. Chambers, H. C. Clark, and C. J. Willis, Chem. and Ind., 1960, 76; H. C.Clark and C. J. Willis, J . Amer. Chem. Soc., 1960, 82, 1888; H. D. Kaesz, S. L. Stafford,and F. G. A. Stone, ibid., 1959, 81, 6336; F. G. A. Stone and P. M. Treichel, Chem. andInd., 1960, 837.+ -145 R. K. Ingham, S. D. Rosenberg, and H. Gilrnan, Clzem. Rev., 1960, 60,469.144 M. C. Henry and J. G. Noltes, J . Amer. Chem. Soc., 1960, 82, 668.145 E. Amberger, Angew.Chem., 1960, 72, 78.146 R. Okawara and E. G. Rochow, J . Amer. Chem. Soc., 1960, 82, 3286; R. Oka-wara, D. E. Webster, and E. G. Rochow, ibid., p. 3287; D. GrdeniC and B. Kamenar,Proc. Chem. SOC., 1960, 312.147 M. F. A. Dove, J., 1959, 3722.148 E. Amberger, Angew. Chem., 1960, 14, 494.149 J. S. Anderson and M. Sterns, J . Inovg. Nuclear Chem., 1959, 11, 272.150 S. I. Morrow, D. D. Perry, and M. S. Cohen, J . Amer. Chem. SOL, 1959, 81, 6338;C. B. Colburn, F. A. Johnson, A. Kennedy, K. McCalIum, L. C. Metzger, and C. 0.Parker, ibid., p. 6397; S. I. Morrow, D. D. Perry, M. S. Cohen, and C. Schoenfelder,ibid., 1960, 82, 5301; R. D. Dresdner, F. N. Tulmac, and J. A. Young, J . Inorg. NuclearChem., 1960, 14, 299; R. H. Sanborn, J . Chem. Phys., 1960, 33, 1855SHARPE: TYPICAL ELEMENTS.129nitrogen tetrafluoride with thiophenol or arsine, and chlorodifluoraminefrom the action of difluoramine on boron trich10ride.l~~The structures of some ammoniates of the ammonium halides have beeninvestigated. Compounds of formula NH,X,3NH3 (X = C1, Br, or I) con-tain the halide ion and the three molecules of ammonia distributed tetra-hedrally around the NH,+ ion; in NH,I,4NH3 the four ammonia moleculessurround the cati0n.1~2 Phase studies reported include NH,-H,02-H20 153and NH3-N13.1aThe interaction of nitric oxide and diethylamine yields the diamagneticcompound Et2NH2+ Et2N-N202-, from which the corresponding sodiumsalt can be prepared by the action of the calculated quantity of sodiume t h 0 ~ i d e .l ~ ~ A study of the temperature dependence of the infrared spectraof the solid dinitrogen tri- and tetra-oxides has been interpreted as indi-cating the existence of one unstable isomer of the former (of structureON*O*NO-the stable form contains a N-N bond) and two unstable isomersof the latter (a twisted form still containing a N-N bond and a form ofstructure ON*O*NO,) .156 Refinements of the structures of nitronium per-chlorate and dinitrogen pentoxide lead to N-0 distances of 1.10 and 1-15(&0.01 A) in the respective nitronium ions; this is very puzzling, since thesymmetrical stretching frequencies (1396 and 1394 cm.-l) are almostidentical.15' A review has been given of the physicochemical properties ofpure nitric acid.15*Phosphorus.A study of the vibrational spectra of trimethylphosphinedihalides suggests that in the solid state these have structures Me,PX+ X-.159Alkylsilylphosphines are obtained by the interaction of lithium derivativesof phosphine or substituted phosphines and alkylchlorosilanes, e.g.,I6OLi,P + 3Me,SiCI ___+c (Me,Si),P + 3LiCITrisdimethylaminophosphine, P(NMe,),, displaces trimethylamine from thecompound Me3N,BH3, and the product is inert towards aqueous acids andalkyl halides and can even be steam-distilled without decomposition ; tri-alkyl phosphites effect similar displacements.161Compounds of formula R,P, (where R = C,H5 or C6Hll) have beenmade from RPH, and RPC1,; the phenyl compound has been shown to addselenium, forming R,P,Se,; and the compound having R = CF, has beenmade by action of trifluoromethyl radicals (generated from fluoroform and151 R.C. Petry, J . Amer. Chem. SOG., 1960, 83, 2400; J. P. Freeman, A. Kennedy,152 I. Olovsson, Acta Chem. Scand., 1960, 14, 1463, 1466.153 P. A. Giguhre and D. Chin, Canad. J . Chem., 1959, 37, 2064.154 G, W. Watt and D. R. Foerster, J . Inorg. Nuclear Chem., 1960, 13, 313, J.155 R. S. Drago and F. E. Paulik, J . Amer. Chem. SOC., 1960, 82, 96.156 I. C, Hisatsune, J. P. Devlin, and Y . Wada., J. Chem. Phys., 1960, 33, 714.157 M. R. Truter, D. J. Cruickshank, and G. A. Jeffrey, Acta Cryst., 1960, 13, 855.158 S. A. Stern, J. T. Mullhaupt, and W. B. Kay, Chem. Rev., 1960, 60, 185.159 J. Goubeau and R. Baumgartner, 2. Elektrochem., 1960, 64, 698.l60 G.W. Parshall and R. V. Lindsey, J . Amer. Chem. SOG., 1959, 81, 6273.161 T. Reetz and B. Katlefsky, J . Amer. Chem. SOC., 1960, 82, 5036; T. Reetz, ibid.,and C. B. Colburn, ibid., 5304.Jander and E. Schmid, 2. anorg. Chem., 1960, 304, 307.p. 5039.REP.-VOL. LvrI 130 INORGANIC CHEMISTRY.benzoyl peroxide at 100') on white ph~sphorus.162 Silver carbonate con-verts the compound (CF,),PI into the anhydride (CF,),P*O*P(CF,),, which issplit by hydrogen chloride :(CF3)2PO*P(CF&, + HCI - (CFJ,PCI + (CFJaP.OHPhosphorus dibromofluoride adds bromine at -75", yielding the corn-pound PBr,F in the molecular form; this slovirly changes into PBr4+F-,which is the stable form at room temperature.lM Complexes of the phos-phorus trihalides which have been described include some with boron tri-bromide, trimethylamine, and triinethylarsine; the trichloride reacts withexcess of methylamine to form a white crystalline solid for which a structureanalogous to that of P406, with NMe groups replacing the oxygen atoms, issuggested.165 Further work on the phosphorus oxychloride solvent systemhas been reported, and it has been shown that the compounds of the oxy-chloride with aluminium or gallium trichloride or titanium tetrachlorideall have oxygen-metal bonds between donor and acceptor.166Details of the structure of trimeric phosphonitrilic chloride have nowbeen given: the molecule consists of an almost flat ring with P-C1 = 1.98,P-N = 1.57-1.61 A, LNPN = 119-121", and LClPCl = 102".Theslight deviation from planarity is attributed to crystal forces, and it is sug-gested that in the vapour phase the molecule would be ~ 1 a n a r .l ~ ~ In solid(PNF,), the ring is planar, with P-N = 1-49-1.52, P-F = 1.50-1.53 A,LPNP = 147O, LNPN = 122-123", and LFPF = 99-100"; in thiscase the Raman and infrared spectra of the gaseous molecule are held tosuggest that it is non-planar.168 Details for the preparations of both chloridesand fluorides have been given,159 and the reactions of the chlorides withammonia, azides, and amines,170 sodium benzoate,171 and ammonium thio-cyanate172 have been described. A diphenyl derivative of the trimer,having both phenyl groups on the same phosphorus atom, is obtained by162 K. Issleib and W. Seidel, 2. anorg.Chem., 1960, 303, 155; I<. Issleib and B.Mitcherling, 2. Naturforsch., 1960, 15b, 267; H.-L. Krauss and H. Jung, ibid., p. 545;W. H. Watson, Texas J . Science, 1959, 11, 471.163 J. E. Griffiths and A. B. Burg, J . Anier. Chem. SOC., 1960, 82, 1507.164 L. Kolditz and K. Bauer, 2. anorg. Chem., 1959, 302, 241.165 R. R. Holmes, J . Inoyg. Nuclear Chem., 1960, 12, 266; J . Phys. Chem.,1960, 64,1295; J. Amer. Chem. Soc., 1960, 82, 5285; R. R. Holmes and J. A. Forstner, ibid.,p. 5509.166 V. Gutmann and F. Mairinger, Monatsh., 1950, 91, 529; M. Baaz, V. Gutmann,and L. Hiibner, ibid., pp. 537, 694; M. Baaz, V. Gutmann, and M. Y . A. Talaat, ibid.,p. 548; R. H. Herber, J . Amer. Chem. Sac., 1960, 82, 792; C.-I. BrandsCn and I. Lind-qvist, Acta Chem.Scand., 1960, 14, 726.167 A. Wilson and D. F. Carroll, J., 1960, 2548.168 H. McD. McGeachin and F. R. Tromans, Chem. avld Ind., 1960, 1131; J. H.Becher and F. Seel, 2. anorg. Chem., 1960,305, 148.165 L. G. Lund, N. L. Paddock, J. E. Proctor, and H. T. Searle, J., 1960, 2542;A. C. Chapman, N. L. Paddock, D. H. Paine, H. T. Searle, and D. R. Smith, J., 1960,3608.170 M. Becke-Goehring, K. John, and E. Fluck, 2. anorg. Chem., 1959, 302, 103;K. John, T. Moeller, and L. F. Audrieth, J . Amer. Chem. Soc., 1960, 82, 5616; M. S.Chang and A. J. Matuszko, ibid., p. 5756.171 I. I. Bezman and W. R. Reed, J . Amer. Chem. SOC., 1960, 82, 2167.172 G. Tesi, R. J. A. Otto, F. G. Sherif, and L. F. Audrieth, J . Amer. Chem. Sac.,1960, 82, 528SHARPE : TYPICAL ELEMENTS.131the action of aluminium chloride and benzene on the chloride; a fullyphenylated polymer has been synthesised by the action of sodium azide onciiphenylchlorophosphine at 160-170°.173 Tri- and tetra-meric bromidesare obtained by the interaction of phosphorus tribromide, bromine, andammonium bromide in sywz.-tetrachloro- or -tetrabr~mo-ethane.l~~ A poly-meric bromide has been made from phosphorus tribromide and sodiumazideJl7, and a fluorinated polymer [(CF,),PN], from the compound (CF,),PCland lithium a~ide.1'~ It has been shown that solvolysis of compounds con-taining A1-H bonds, e.g., complexes of aluminium hydride, in dimethyl-phosphine leads to the formation of compounds containing Me,P-A1 links,but details have not yet been given.176The exchange of tritium between water and hypophosphorous acid hasthe same rate law as the oxidation of the acid by a variety of reagents; thissuggests that both take place by the same mechanism, which is believed toinvolve the formation of a tautomer of structure HP(OH),.177 Whenpotassium monophosphates are treated with acetic acid-acetic anhydrideat go", the pure trimetaphosphate K,P,O, is formed in a new modificationwhich has the same structure as p-(KAsO,), and the corresponding arseno-phosphates.178 Phosphoryl trihydrazide, PO(NH-NH,),, can be made fromphosphoryl chloride and hydrazine in ethanolic suspension at - 12°.179Phosphorus thiochloride and phosphorus pentoxide react to form com-pounds of formulz P,O,SCl, and P405S2Cl,, for which the structuresCl,P(O) *P (S) C1, and Cl,P(S) *O*PCl(O) *O-PCl(O)*O*P(S) C1, are suggested.lsORaman and infrared spectroscopic studies of the peroxydiphosphates showthat the P,OS4- ion has the same structure as the peroxydisulphate ion.181When imidophosphates are hydrolysed by dilute acid, appreciable quantitiesof P-0-P linked compounds are formed via ammonia-eliminating con-densations of the amides which are intermediates; hydrolysis of trimeta-phosphimate at pH 3.5, for example, gives a di-imidotrimetaphosphate.la2The existence of a new phosphorus sulphide, obtained from melts of com-positions within the range P,S~-P&,.SJ has been reported.lS3 The struc-ture of P4S3 as a tetrahedron of phosphorus atoms with sulphur atoms offthree of the edges has been confirmed, and the reactions between P4S3 orP4S5 and liquid ammonia at -33" have been shown to give the compounds(NH,) , [P4S3( NH,) ,] and (NH,) [P4S5 ( NH,),], re~pective1y.l~~173 D.L. Herring, Clzem. and Ind., 1960, 717; M. Becke-Goehring and I<. John,K. John and T. Moeller, J . Amer. Chem. Soc., 1960, 82, 2647; N. E. Bean andG. Tesi, C. P. Haber, and C . M. Douglas, Proc. Chem. Soc., 1960, 219.176 A. B. Burg and K. Modritzer, J . Ipzorg. Nuclear Chem., 1960, 13, 318.W. A. Jenkins and D. M. Yost, J . Inorg. Nuclear Chem., 1959, 11, 297 (cf. A. D.I. Grunze, K. Dostal, and E. Thilo, 2. anorg. Chem., 1959, 302, 221.170 R. Klement and K. 0. Knollmiiller, Ber., 1960, 93, 834.180 E. Rother, Ber., 1960, 93, 2217.-4. Simon and H.Richter, 2. anorg. Chem., 1960, 304, 1.lS2 0. Y . Quimby, A. Narath, and F. H. Lohman, J . Amer. Chem. Soc., 1960, 82,183 G. A. Rodley and C. J. Wilkins, J . I9zovg. Nuclear Chem., 1960, 13, 231.P. -2. Akishin, N. G. Rambidi, and Y . S. Ezhov, Zhur. neorg. Ii?zim., 1960, 5,2. anorg. Ckent., 1960, 304, 126.R. A. Shaw, Chem. and I n d . , 1960, 1189.Mitchell, J., 1923, 123, 629).1099.747 [358]; H. Behrens and L. Huber, Ber., 1960, 93, 921132 INORGANIC CHEMISTRY.Arsenic, antimony, and bismtxth. A nuclear magnetic resonance studyof the compound 2AsF,,3S03 suggests that it has structure (4) .lS5The preparation and properties of mixed alkyl and aryl perfluoroalkylarsenicals have been described.ls6 The compound (Ph,SiO),As has beenmade by the interaction of sodium triphenylsilyloxideF and arsenic trichloride ; interaction of diphenyldi-chlorosilane and potassium dihydrogen arsenate F, AsO&O0 0 I \ gives the compoundo*;-o-~:* (4) (HO) ,As (0) [O.SiPh,*O*As (0) (OH) ],*OHwhich slowly decomposes to form a polymer of F'b F\ / composition [O*SiPh,*O*As(O) (OH)],.The com-As pound As* [O*SiPh,-O],*As is made by co-hydrolysisof arsenic trichloride and diphenyldichlorosilane or IFby interaction of arsenic trichloride and diphenyl-silanediol in the presence of trimet hylamine or ammonia.lS7Stibine is formed in 25% yield by the action of potassium borohydrideon antimony trichloride in aqueous solution.lss The system SbC15-HF hasbeen restudied: a t -75", HSbC1,F is formed: above -40°, substitution offluorine for chlorine begins, three substitutions being fast, the fourth takingplace only above Oo, and the last one being very slow indeed.lsg Antimonytrichloride combines with acetone to form a compound SbC13,2Me,C0 andwith trimethylphosphine oxide to form SbCl,,Me,PO.It has been shownthat although the trimethylphosphine oxide complexes of the tri- and penta-chlorides show about the same shift of the P-0 stretching frequency theirenthalpies of formation from the constituent molecules are widely different ;the use of Av as an indication oi electron acceptor strength is permissibleonly if the changes in structure of the acceptor molecules are very similar.lgOContrary to earlier reports, antimony tri-iodide is decomposed by ammonia,first to Sb(NH,),I, then to the nitride (arsenic tri-iodide gives only thenitride).lgl The iodide Sb214 appears to be present in solutions of antimonyin the molten tri-iodide.lg2 Antimony pentachloride and sodium ethoxideyield antimony ethoxides which conduct in polar solvents, having, in theseonly, structures of the type [SbCl,(OEt),,] [SbClb(OEt)6-b].In non-polarsolvents molecules [SbCl,(OEt),j predominate.lg3 In stibnite, Sb,S6, halfof the antimony atoms in the ribbon-like polymer are five-co-ordinated,being 0.12 A below the basal plane of the SbS, square pyramid; this type ofstructure appears to be general for five-co-ordinated antimony(II1) .lg4Cryoscopic investigations of solutions of bismuth in the molten tri-chloride, and vice veysa, suggest that subchlorides, BiCl and Bi,Cl,, are present1e5 R.J. Gillespie and J. V. Oubridge, Proc. Chem. SOC., 1960, 308.la6 W. R. Cullen, Canad. J . Chem., 1960, 38, 439, 445, 472.187 B. L. Chamberland and A. G. MacDiarmid, J . Amer. Chem. SOC., 1960, 82, 4542.188 L. Berka, T. Briggs, M. Millard, and W. Jolly, J . Inorg. Nuclear Chem., 1960,189 L. Kolditz and H. Daunicht, 2. anorg. Chem., 1959, 302, 230.190 M. Zachrisson and K. I. Aldh, Acta Chem. Scand., 1960, 14, 994.I9l H. Remy and G. Tiedemann, Nuturwiss., 1960, 47, 178.192 J. D. Corbett and F. C. Albers, J . Amer. Chem. SOC., 1960, 82, 533.Ig3 L. Kolditz and S. Engels, 2. anorg. Chem., 1959, 302, 88.194 D. GrdeniC and S. SCavniCar, Proc. Chem. SOC., 1960, 147; S.SCavniEar, 2. Krist.,14, 190.1960, 114, 85SHARPE: TYPICAL ELEMENTS. 133in metal-rich and halide-rich solutions, respe~tive1y.l~~ Bismuth penta-fluoride melts at 161" and has the a-uranium pentafluoride structure, in whichMF, octahedra share two opposite corners to give a chain of compositionMF, ; it fluorinates bromine, uranium dioxide, and uranium tetrafluoride at150-180°.196 The hydrolysis of the Bi3+ ion in water results in the form-ation of species Bi,0G6+ (in nkutral solution) and Bi,0,(OH)33+ (at high pH) ;the six bismuth atoms in the cation are in octahedral arrangement.lg7Group V1.-Recent reviews have dealt with halides and oxyhalides ofGroup VI elements,lg8 dimethyl sulphoxide as a solvent and complexingagent,lW amides and imides of oxyacids of sulphur,200 and the structures ofcompounds containing chains of sulphur atoms.201Claims to have prepared a superoxide of formula H20? by the action ofhydrogen atoms on ozone at -196" appear to be unjustified: only water,hydrogen peroxide, and ozone have been found by infrared spectroscopicexamination of the residue from the reaction.202 The structure of hydrogenperoxide &hydrate has been shown to consist of planar chains of watermolecules connected by hydrogen bonds and cross-linked by hydrogen bond-ing with peroxide molecules into a three-dimensional netw0rk.~O3Much new work on sulphur fluorides has been published, and a review hasbeen given.204 A convenient synthesis of the tetrafluoride is by the action ofsulphur dichloride on sodium fluoride suspended in acetonitrile ; the sameagent is also useful for the replacement of chlorine in oxyhalides or organiccompounds of sulphur by fluorine.205 Sulphur tetrafluoride fluorinates manyinorganic compounds (e.g., compounds of tungsten, molybdenum, and uran-ium) and appears to be a very useful reagent for the preparation of organicfluorine compounds.206 Sulphur chloride pentafluoride, SF,Cl, is obtainedby the fluorination of sulphur dichloride; it is a colourless gas, liquefying at--21", which is inert to acids but is rapidly and completely hydrolysed byalkalis, and which on irradiation with ultraviolet light in the presence ofoxygen is converted into the compounds (SF,),O and SF5*0*0*SF5.207 Theoxide tetrafluoride SOF, is made by the action of oxygen on the tetra-fluoride in the presence of catalytic amounts of nitrogen dioxide, or by theoxidation of the same compound with chromium trioxide or cerium dioxide ;the former method is preferable.It reacts with ammonia to give ammonium195 S. W. Mayer, S. J. Yosim, and L. E. Topol, J . Phys. Chem., 1960, 64, 238.196 J. Fischer and E. Rudzitis, J . Amer. Chem. SOC., 1959, 81, 6375.197 H. A. Levy, M. D. Danford, and P. A. Agron, J . Chem. Phys., 1959, 31, 1848;l D 8 J. W. George, Prog. Inorg. Chem., 1960, 2, 33.lSs H. L. Schlafer and W. Schaffernicht, Angew. Chem., 1960, 72, 618.200 M. Becke-Goehring, Adv. Inorg. Chem. Radiochem., 1960, 2, 159.201 0. Foss, Adv. Inorg. Chem. Radiochem., 1960, 2, 237.202 P.A. Giguere and D. Chin, J . Chem. Phys., 1959, 31, 1685.208 I. Olovsson and D. H. Templeton, Acta Chem. Scand., 1960, 14, 1325.204 G. H. Cady, Adv. Inorg. Chem. Radiochem., 1960, 2, 105.205 C. W. Tullock, F. S. Fawcett, W. C. Smith, and D. D. Coffman, J , Amer. Chem.Soc., 1960, 82, 539; C. W. Tullock and D. D. Coffman, J . Ovg. Chem., 1960, 25, 2016.206 A. L. Oppegard, W. C. Smith, E. L. Muetterties, and V. A. Engelhardt, J . Amer.Chem. SOC., 1960, 82, 3835; W. R. Hasek, W. C. Smith, and V. A. Engelhardt, ibid.,p. 543; W. C. Smith, C. W. Tullock, R. D. Smith, and V. A. Engelhardt, ibid., p. 551;C. W. Tullock, R. A. Carboni, R. J. Harder, W. C. Smith, and D. D. Coffman, ibid.,p. 5107.SO7 H. L. Roberts and N. H. Ray, J., 1960, 665; H. L. Roberts, J., 1960, 2774.R.S. Tobias, J . Amer. Clzem. Soc., 1960, 82, 1070134 INORGANIC CHEMISTRYfluoride and the ammonium salt of the hitherto unknown imide F,S(O)NH;when the mixture is heated a colourless polymeric residue of composition[SF(0)=Nln is formed.208 Phenylsulphur trifluoride is obtained by theaction of argentic fluoride on a solution of diphenyl sulphide in a " Freon,"and is converted by the further action of argentic fluoride into phenyl-sulphur pentaflu~ride.~~~ Among new sulphur compounds containing thetrifluoromethyl group are CF,*S*NH,, (CF,*S),NH, (CF,*S),PH, and(CF,*S),P ; these result from the action of trifluoromethanesulphenylchloride on ammonia or phosphine ; bis(trifluoromethy1thio)mercury reactswith phosphorus and arsenic chlorides to yield compounds of the types R,M,R,MCl, and RMCl,, where R = CF3*S.210Trimethylsulphonium borohydride has been made from the fluoride andsodium borohydride in ethanol.211 It decomposes at go", forming methaneand the borane adduct of dimethyl sulphide.In the compound S,N,,SbCl, the antimony atom is octahedrally co-ordinated by five chlorine and one nitrogen atoms; the N-S bonds formedby the donor atom are noticeably longer (1.74, 1.69 A) than others in thering (1.53-1.61 A) .,12 Hexasulphur di-imide, S,(NH),, has a puckeredeight-membered ring, the NH groups occupying the 1,5 po~itions.~~3 Thecompound NSF is prepared by boiling a mixture of sulphur nitride andargentic fluoride in a carbon tetrachloride suspension; it is a colourless gascondensing to a yellow liquid (f.p. -89"), and is readily h y d r o l y ~ e d . ~ ~ ~Fluorosulphonates of bromine and iodine, the compounds BrO*SO,F (adark red liquid), Br(O*SO,F), (m. p. 59"), and I(O-SO,F), (m. p. 32"), havebeen made by treating peroxydisulphuryl fluoride (S206F2) with the appro-priate halogen; by the action of the compound FO*SO,F on iodine an un-stable liquid of formula IF,(O*SO,F), is obtained.,15 Bromosulphonic acidhas been prepared from hydrogen bromide and sulphur trioxide in liquidsulphur dioxide at -35"; it is a pale yellow solid, m. p. -8", which decom-poses at its melting point into bromine, sulphur dioxide, and sulphuric acid.216Chlorosulphonic acid reacts with silver thiocyanate at -50" in the presenceof ether to yield a solution of the unstable acid NCS*S0,*OH.217A study of the ultraviolet absorption spectra of bisulphite solutions ofvarious concentrations shows that the principal anions present are HO*S02-(at low concentrations) and H*SO,- and S,O,,- (at high concentrations).The compounds RbHSO, and CsHSO, have been isolated from the liquidsobtained by the action of sulphur dioxide on 50% solutions of the carbonatesor hydroxides; their vibrational spectra indicate that they contain tetra-208 W.C. Smith and V. A. Engelhardt, J. Amer. Chem. SOC., 1960, 82, 3838; I;. See1and G. Simon, Angew. Chem., 1960, 72, 709.209 W. A. Sheppard, J. Amer. Chem. SOC., 1960, 82, 4751.210 H. J. EmelCus and S. N. Nabi, J., 1960, 1103; H. J. EmelCus and H.Pugh,J., 1960, 1108.211 H. G. Heal, J . Inorg. Nuclear Chem., 1960, 12, 255.212 D. Neubauer and J. Weiss, 2. anorg. Chem., 1960, 303, 28.21s J. Weiss, 2. a.pzorg. Chem., 1960, 305, 190.214 0. Glemser, H. Richert, and F. Rogowski, Nuturwiss., 1960, 47, 94.215 J. E. Roberts and G. H. Cady, J . Amer. Chem. SOC., 1960, 82, 352, 353,216 M. Schmidt and G. Talsky, 2. anorg. Chem., 1960, 303, 210.217 M. Schmidt and G. Talsky, Ber., 1960, 93, 719.354SHARPE TYPICAL ELEMENTS. 136hedral HS0,- ions.21* When potassium thiosulphate is suspended in acetoneat -78" and treated with disulphur dichloride and hydrogen chloride,hexathionic acid is formed in good yield.219 By the interaction of dihydrogenhexasulphide and sulphur trioxide in a " Freon," the unstable acid H2S,0,is obtained; sulphur trioxide converts this into another acid, H,S,O,, andiodine oxidises it to a very unstable compound of formula H2S1406.220 Saltsof the unknown peroxytetrasulphuric acid, H2S4OI4, have been obtained bythe action of sulphur trioxide on alkali metal peroxides, superoxides, orperoxydisulphates at low temperature in the presence of sulphur dioxide.Z21The Raman spectra of oleums provide no evidence for the presence of tri-or higher sulphuric acids.222 Electrolytes in 65% oleum behave analogouslyto those in sulphuric acid, and the HS,O,- ion is the main carrier of current.Boron trichloride and oleum give the compound B(HS,O,), which adds ananion forming B(HS,O,),-.No ions are present in the blue solution formedby dissolving sulphur in 01eum.~~~When selenium oxychloride combines with stannic chloride to form thecompound (Cl,SeO),SnCl,, oxygen is the donor atom and the oxychloridemolecules occupy cis-positions in the octahedron round the tin atom.224The Raman spectra of the compounds RSeO*OH,HCl (where R = Me or Et)show these compounds to possess structures [RSe(OH)2]C1.225 In solidpyroselenites, M,Se,O,, the structure of the anion appears 226 to be0,Se*O*Se022-; in aqueous solution the species is HO-SeO,-.A polymericselenium nitride of empirical formula SeN is obtained by the action ofselenium dioxide, tetrachloride, or tetrabromide on liquid ammonia; theproduct is identical with that formed from ethyl selenite and ammonia inbenzene.227Tracer work has indicated the existence of a volatile fluoride ofpolonium.228Group VII.-A new review periodical 229 devoted to fluorine chemistryhas appeared, and two lectures on recent developments in fluorine chemistryhave been published.=O A large number of double and complex fluorideshave been made by mixing methanolic solutions of alkali-metal fluoridesand bromides of other metals (e.g., Bi, Cd, Co, Cu, Mn, Ni, Zn, Fey Zr); theoccurrence of hydrogen bonding in some of these compounds is discussed.231The formula of chlorine hydrate has been redetermined as C1,,7.3H20,which corresponds to the filling of all the medium-sized and 20% of the small918 R.M. Golding, J., 1960, 3711; A. Simon and W. Schmidt, 2. EIek,frochem.219 M. Schmidt and B.Wirwohl, 2. anorg. Chem., 1960, 303, 177.230 M. Schmidt and H. Dersin, 2. Naturforsch., 1959, 14b, 735.221 M. Schmidt and H. Bipp, Z. anorg. Chem., 1960, 303, 201.228 G. E. Walrafen and T. F. Young, Trans. Faraday SOC.. 1960, 56, 1419.223 J. Arotsky and M. C . R. Symons, Trans. Faraday SOC., 1960, 56, 1426.224 Y. Hermodsson, Acta Cryst., 1960, 13, 656.228 R. Paetzold, H.-D. Schumann, and A. Simon, 2. anorg. Chem., 1960, 305, 98.226 A. Simon and R. Paetzold, 2. anorg. Chem., 1960, 303, 39, 46.227 J. Jander and V. Doetsch, Ber., 1960, 93, 561.228 B. Weinstock and C. L. Chernick, J . Amer. Chem. SOC., 1960, 82, 4116.229 Adv. Fluovine Chern., 1960, 1 (Butterworths, London).230 G. H. Cady, Proc. Chem. SOC., 1960, 133; H. J. EmelCus, ibid., p. 234.231 D.S. Crocket and H. M. Haendler, J . Amer. Chew. SOL., 1960, 82, 4168.1960, 64, 737136 INORGANIC CHEMISTRY.holes in the structure of Chlorine complexes with dioxan and withbenzene are isostructural with the well-known bromine complexes.233Hydrogen chloride as an ionising solvent has received further study, andconductivity data and neutralisation reactions are reported.= The absorp-tion spectra of the solution obtained by interaction of chlorine and mercuricacetate in anhydrous acetic acid (" chlorine acetate," C1*O*COCH3) and ofsimilar solutions containing 0.5% of water show that in the latter hydrolysisto hypochlorous and acetic acids is practically complete.235Ammonolysis of perchloryl fluoride, C103F, with liquid ammonia givesammonium fluoride and a compound NH,(HNClO,), the reaction beinggreatly accelerated by the presence of sodamide.A similar reaction takesplace with aqueous ammonia, and from the resulting solution rubidium orczsium salts precipitate explosive compounds M2NC103, isomorphous withthe corresponding sulphates, and MHNClO,, almost isomorphous with theperchlorates .236Bromine reacts with hydrogen sulphide in chloroform or methylenechloride under rigidly controlled conditions according to the schemeBr, + H,S ___t HBr + HSBrand at low temperatures the salt NH,SBr can be isolated.%'In the compound Me,N,ICl the N-I-C1 skeleton is linear, with I-CI = 2.52and N-I = 2.30 A.238 In the dithian-iodine complex it is interesting tonote that although the ligand appears to be unchanged by complex form-ation the 1-1 distance in the acceptor molecule is increased by 0.11 k 2 3 9The electrolysis of a solution of the compound Ipy2F in acetonitrile yieldsthe compound IPYF,.~,O When fluorine, diluted with nitrogen, reacts withiodine in a '' Freon '' a t -78O, iodine trifluoride is obtained as a yellowpowder; it combines with pyridine, yielding the compound Ipy2F3, anddecomposes slowly above -35" to iodine and iodine pentafluoride.Itreacts with iodine to give chocolate-brown iodine monofluoride; this alsoreacts with pyridine (forming IpyF) and disproportionates above OO.241Tetrafluoroiodates(IIr), MIF,, where M = K, Rb, or Cs, are produced bythe action of iodine pentafluoride on the iodides ; the solvated compoundsCs12Fg and Me,N12F, have also been obtained.All are white powderswhich are decomposed by moisture.242 A re-examination of the electron-diffraction photographs suggests that although the main features of thepentagonal bipyramidal structure of iodine heptafluoride are correct , thefive girdle fluorine atoms probably form a puckered ring rather than a planarone; this interpretation would be in agreement with the previously reported232 K. W. Allen, J., 1959, 4131.233 0. Hassel and K. Stramme, Acta Chem. Scand., 1959, 13, 1775, 1781.234 T. C. Waddington and F. Klanberg, J., 1960, 2329, 2333.235 P. B. de la Mare, I. C. Hilton, and C. A. Vernon, J., 1960, 4039.238 H. C. Mandell and G. Barth-Wehrenalp, J . Inorg. Nuclear Chem., 1959, 12, 90.237 M. Schmidt and I.Lowe, Angew. Chem., 1960, 72, 79.238 0. Hassel and H. Hope, Acta Chem. Scand., 1960, 14, 391.239 G. Y . Chao and J. D. McCullough, Aeta Cryst., 1960, 13, 727.240 H. Schmidt and H. Meinert, Angew. Chem., 1960, 72, 109.241 M. Schmeisser and E. Scharf, Angew. Chem., 1960, 72, 324.2*2 G. B. Hargreaves and R. D. Peacock, J., 1960, 2373SHARP: TIIE TRANSITION ELEMENTS 137disorder in the solid state and the unusually broad nuclear magneticresonance spectrum of the liquid.243A study of the infrared and visible spectra of iodosyl sulphate andselenate, iodine dioxide, and ‘‘ iodosobenzene dinitrate ” [now shown tohave the structure Ph-L (O-NO,)*O*I (O*NO,)*Ph] leads to the conclusion thatthe iodosyl cation present in the first three compounds is polymeric andcontains 1-0-1 bridges.244 The infrared spectra of sodium periodate tri-hydrate and its aqueous solution suggest that both contain the H410,-ion.245Astatine iodide, AtI, has been shown to crystallise with iodine fromchloroform,246 and the existence of a dipyridine-stabilised cation of astatinehas been demonstrated by showing that astatine accompanies iodine whensuch salts are isolated.247A.G. S.3. THE TRANSITION ELEMENTSTHE transition elements will be considered in an order similar to that adoptedlast year. An extra section on hydrides has been included in which coni-pounds containing a G metal-hydrogen bond are discussed; cyanides arenow considered under the heading of the appropriate element. Generalreviews on transition-metal chemistry published during the year includearticles on the interstitial hydrides and transition-metal fluorides andcomplex fluorides.2The physical methods most used in the studyof complex compounds have been discussed in an important new book?General reviews include articles on the stereochemistry of ionic solids withparticular attention being paid to the effect of d electrons on stereo-chemistry; 4 intensities of spectral bands in transition-metal complexes ; 5the redox potentials of metal complexes; and the study of metal complexesby distribution methods.’ There has also been the report of a symposiumon chelation phenomena with many papers describing the reactions oftransition-metal complexes.8Theoretical studies have been made on the effect of partial covalency onthe results of ligand-field theory; particular interest was shown in the243 R.E. LaVilla and S. H. Bauer, J . Chem. Phys., 1960, 33, 182.244 W. E. Dasent and T. C. Waddington, Proc. Chem. Soc., 1960, 71; J., 1960, 3350.245 N. Keen and M. C. R. Symons, Proc. Chem. SOG., 1960, 383.IL46 A. H. W. Aten, J. G. van Raaphorst, G. Nooteboom, and G. Blasse, J . Inorg.247 J. J. C..Schats and A. H. W. Aten, J . Inorg. Nuclear Chem., 1960, 15, 197.Complexes.-(a) GefieraE.Nuclear Chem., 1960, 15, 198.G. G. Libowitz, J . Nuclear Materials, 1960, 2, 1.2 A. G. Sharpe, Adv. Fluorine Chem., 1960, 1, 29; R. D. Peacock, Progr. Inorg.3 J. Lewis and R. G. Wilkins (Eds.), “ Modern Co-ordination Chemistry,” Inter-Chem., 1960, 2, 193.science Publishers Inc., New York, 1960.J.D. Dunitz and L. E. Orgel, Adv. Inorg. Chem. Radiochem., 1960, 2, 1.C. J. Ballhausen, Progr. Inorg. Chem., 1960, 2, 251.D. D. Perrin, Rev. Pure Apfil. Chem. (Australia), 1959, 9, 257.A. P. Zozulya and V. M. Peshkova, Uspekhi Khim., 1960, 234 [loll.*Ann. New York Acad. Sci., 1960, 88, 283.* The figures in square brackets refer to the page numbers of the English translation138 INORGANIC CHEMISTRY.application of the results of these theories to second- and third-row transitionmetal^.^ The theoretical aspects of eight-co-ordinate compounds with the[Mo(CN)J4-, dodecahedral, structure have also been considered and it isconcluded that four of the sites are especially available to n-bonding ligands,an observation in accord with the ready formation of mixed complex ionssuch as p(CN),(OH),]4- and [Re(diarsine),Cl,]+ ; lo however, the Ramanspectrum of K4Mo(CN),,2H,0 in aqueous solution suggests that the freeanion has the Archimedean antiprism structure,ll and a further investigationof the structures of some other 8-co-ordinate molybdenum complexesappears necessary.A preliminary study of oxygen-17 nuclear magneticresonance spectra of aqueous solutions shows that it is possible to distinguishsolvent water from hydration-sphere water; this should permit the exactdetermination of co-ordination number in aqueous solutions.12 The spectraand differences in reactivity of transition-metal ions when dissolved in waterand deuterium oxide have been studied.The differences are limited toions with water in the hydration sphere and are due to the different dipoles,zero-point energies, vibrational quantum numbers , and extents of hydrogenbonding of the two solvents.l3 Detailed studies of the heats and entropiesof reaction of transition-metal ions with ethylenediamine show that , aftercorrection for the ligand-field stabilisation energies, the corrected heats donot vary linearly with atomic number but that the variation is similar tothat observed in the formation of metal hydrates.14 The enthalpy andentropy terms for the reaction of diacetyl di(benzoylhydrazino)nickel(xI)with primary alkylamines show that the donor ability of the amine increaseswith the length of the alkyl group and is proportional to the inductiveeffect of substituents. Steric effects are only important for branched-chainalkyl groups and for trialkylamines.The greater stability of trialkyl-phosphine complexes is attributed to weaker steric effects and the bond-ing is considered as essentially Q in character, even in the phosphinec0mp1exes.l~Further work has been published on the chemical reactions of diketoneschelated to transition-metal ions. Copper complexes react with nitro-benzoyl chlorides to give triketones which can be deacylated to P-diketones.The central carbon atom of the chelate ring undergoes ready electrophilicsubstitution by the halogens and by copper nitrate dissolved in acetic an-hydride.16 The formation of metalloporphyrins M2+ + RH, + 2H,O *RM + 2H30+ (R = porphyrin residue) has been shown to occur through anintermediate, and a sitting-atop type complex [see (1) for the reaction inter-mediate in the case of the formation of the ferric complex] has been postul-9 A.D. Liehr, J . Phys. Chem., 1960, 64, 43.10 L. E. Orgel, J . Inorg. Nuclear Chem., 1960, 14, 136.11 H. Stammreich and 0. Sala, 2. Elektrochem., 1960, 64, 741.12 J. A. Jackson, J. F. Lemons, and H. Taube, J . Chem. Phys., 1960, 32, 553.13 J. Bigeleisen, J . Chem. Phys., 1960, 32, 1583; cf. J. Halpern and A. C. Harkness,ibid., 1959, 31, 1147.14 M. Ciampolini, P. Paoletti, and L. Sacconi, J., 1960, 4553.15 L. Sacconi, G. Lombardo, and R. Ciofalo, J . Amer. Chem. SOL, 1960, 82, 4182;L. Sacconi, G. Lombardo, and P.Paoletti, ibid.. p. 4185.16 W. J. Barry, J., 1960, 670; J. P. Collman, R. A. Moss, S. D. Goldby, and W. S.Trahanovsky, Chem. and Ind., 1960, 1213; R. W. Kluiber, J . Amer. Chem. Soc., 1960,82, 4839SHARP : THE TRANSITION ELEMENTS. 139ated l7 Tetracyanoethylene forms metal complexes ; these are formulated(2) to be similar to the phthalocyanines.l8 The behaviour of metal tetra-fluorides with a variety of organic donor molecules shows that most donorsform 2 : 1 cis-complexes with the metal fluorides. It has previously beenHI I c=cpostulated that zirconium and tin tetrachlorides form complexes,MC14,2R*C0,H, in which the orientation is cis, and this appears to be a generalrule in octahedral halide complexes of this type. Amide complexes withmetal tetrafluorides are considered to be co-ordinated to the metal throughthe oxygen at0rn.1~ There has been a great deal of interest in the use oforganic solvents for dissolving inorganic compounds ; in many cases solvatesare formed on crystallisation.Solvents studied include dimethyl sulph-and dimethyl- and diphenyl-formamide.21 Co-ordination can bethrough the oxygen or the other donor atom in the ligand and infraredspectra can be used to distinguish between these possibilities. The two ions[Rh(NH,),(ON0)]2+ and [Ir(NH,),(ON0)]2+ have been synthesised; bothare readily converted into the corresponding nitro-complexes. These are thefirst new nitrito-complexes to be made since the pentamminecobalt (111) salts,although nuclear magnetic resonance studies on sodium cobaltinitrite solu-tions show the presence of two complex anions and it has been suggestedthat a nitrito-species is in equilibrium with a nitro-species.22 A novel typeof isomerism (3 and 4) which depends on the position of the bridging thiolgroups has been observed for thiol-bridged complexes of platinum(I1) -23Complex formation often induces an unusual conformation into an organicl7 E.B. Fleischer and J. H. Wang, J . Amer. Chem. SOL, 1960, 82, 3498.18 A. A. Berlin, N. G. Mateeva, and A. I. Sherle, Izvest. Akad. Nauk S.S.S.R.,Oldel. klzim. Nauk, 1959, 2261 [2164].19 E. L. Muetterties, J . Amer. Chem. SOC., 1960, 82, 1082; cf. 0. A. Osipov and V. B.Kretenik, J . Gen. Chem. (U.S.S.R.), 1957, 27, 2953; 0. A. Osipov, G.S. Samofalova,and E. I. Glushko, ibid., p. 1502.20 F. A. Cotton and R. Francis, J . Amer. Chew. SOC., 1960, 82, 2986; I?. A. Cotton,R. Francis, and W. D. Horrocks, jun., J . Phys. Chem., 1960, 64, 1534; H. L. Schlaferand W. Schaffernicht, Angew. Chenz., 1960, 72, 618; D. W. Meek, D. K. Straub, andR. S. Drago, J . Amer. Chem. SOC., 1960, 82, 6013; J. Kenttamaa, Suomen Kenz., 1960,33, B, 179.21 J. Archambault and R. Rivest, Canad. J . Chem., 1960, 38, 1331; P. Ehrlich andW. Siebert, 2. anorg. Chem., 1960,303, 96; T . Moeller and V. Galasyn, J . Inorg. NuclearChern., 1960, 12, 259; T. Moeller, V. Galasyn, and J. Xavier, ibid., 1960, 15, 259;S. Buffagni and T. M. Dunn, Nature, 1960, 188, 937.22 F. Basolo and G. S. Hammaker, J . Amer. Chem.Soc., 1960, 82, 1001 ; R. P. H.Gasser and R. E. Richards, Mol. Phys., 1960, 3, 163.23 J. Chatt and F. A. Hart, J., 1960, 2807140 INORGANIC CHEMISTRY.ligand. Piperazine (5) derivatives generally have a chair configuration butin 1,4-dirnethylpiperazinepalla&um(11) chloride the six-membered ring is/Ptk / P t \ (4)CI s CIEtpresent in a boat form.= An X-ray study of trisethylenediaminenickel(11)nitrate shows that the cation is either D-111 or L-add in configuration; theethylenediamine groups have the configuration gaz,jche-gazache-gauche.25Complexes containing phosphorus compounds as ligands have been exten-sively studied. Particular classes of ligands that have received specialattention are the triarylphosphine oxides, sulphides, and selenides,26 di-ethylphosphine, dicyclohexylphosphine, diphenylph~sphine,~' and PPP'P'-tetraethylethylene-1,2-dipho~phine.~ The considerations that must befollowed when designing quadridentate ligands have been fully discussed.2QInfrared spectra of metal complexes continue to be widely studied.Themetal-nitrogen stretching frequencies in metal-hydrazine complexes followthe Irving and Williams order for the stability of The N-Hstretching frequencies of the complexes trarts-(L,R*NH2PtC12) (L = C2H,or PEt,; R = Me, Et, Pri, or But) have been interpreted in terms ofrestricted rotation about the platinum-nitrogen bond , steric repulsionbetween R and the chlorine atoms, intermolecular hydrogen bonds, andhydrogen bonding between the nitrogen and non-bonding d orbitals on themetal. This list factor is similar to the hydrogen bonding found in ferrocene-carboxylic acid.s1In view of the verylarge literature on this subject only a few papers which seem to illustrategeneral principles will be considered. The mechanisms and rates of reactionof complex ions have been fully reviewed during the year 32 and a separatereview has been published on electron-transfer reactions.= Orienting effectsin the aquation of octahedral complexes have been discussed in terms of the(b) Mechanism of reactions of inorganic complexes.24 0.Hassel and B. F. Pedersen, Proc. Chem. SOC., 1959, 394.25 L. N. Swink and M. Atoji, Acta Cryst., 1960, 13, 639.26 F. A. Cotton and E. Bannister, J., 1960, 1873; E. Bannister and F.A. Cotton,27 K. Issleib and G. Doll, 2. anorg. Chem., 1960, 305, 1 ; K. Issleib and E. Wenschuh,28 C. E. Wymore and J. C. Bailar, jun., J. Inorg. Nuclear Chem., 1960, 14, 42.29 H. A. Goodwin and F. Lions, J . Amer. Chem. SOC., 1960, 83, 6013.80 L. Sacconi and A. Sabatini, Nature, 1960, 186, 649.31 L. A. Duncanson and L. M. Venanzi, J., 1960, 3841; D. S. Trifan and R. Bacskai,J . Amer. Chem. SOC., 1960, 82, 5010.32 D. R. Stranks, ref. 3, p. 78.33 A. C . Wahl, 2. Elektrochem., 1960, 64, 90.J , , 1960, 1959.ibid., p. 15SHARP : THE TRANSITION ELEMENTS. 141electronic effects of the ligands.34 For octahedral metal ammines the rate ofproton exchange decreases with decrease in overall charge on the complexion and with increase in the atomic number of the central metal atom.The rates of exchange of square planar ammines change in the oppositeway.% Oxidation and reduction reactions of the actinide ions continue tobe studied.Most of the reactions proceed via activated complexes such as(Pu*Cl,.Sn)2+, (PuC1,Sn) +, or (UOH*Np0,)5+ 36 In acidic aqueous sulphatesolutions the rate-determining step for the oxidation of chromium(II1) withcerium(1v) species appears to be the reaction of a chromium(1v) species withthe ceric ions.37 The hexa-aquochromium (111) and aquopentammine-cobalt (111) ions undergo a second-order photochemically induced sub-stitution with thiocyanate and chloride ions. The mechanism appears tobe by way of a photochemically induced exchange of ligands in an ion-pair.=The relative efficiencies of complex chromous salts as catalysts for exchangereactions of chromium(II1) complexes are the same as the relative stabilitiesof the Cr(I1) complexes; this is interpreted as being due to the effect of thenon-bridging ligands on the chromium(II)-chromium(rII) electron exchange.39Two possible mechanisms have been suggested for the acid- and base-catalysed hydrolysis of cobalt(II1) ammines.Study of the rate of hydrogenexchange suggests a conjugate base (SN~ CB) mechanism for the exchanges,and a study of base-catalysed reactions in non-aqueous solvents, where thereaction product should depend on the mechanism, gives further evidence infavour of this mechanism.4O There are important differences in the effectsof one- and two-electron oxidising agents on cobalt(II1) complexes.Thus,the reaction of the penta-ammineoxalatocobalt (111) ion, [(NH3)5C~(C204)]+,with a one-electron oxidising agent [Ce(rv), CoBfaq, S,0,2--Ag+] gvesCo2+, CO,, and NH,+, but a two-electron oxidising agent [H,02-Mo(v~), Cl,]gives the [(NH,),CoOHJ3+ ion and the oxidation state of the cobalt is notaffected. Similarly, the penta-ammine-fi-formylbenzoatocobalt (111) ion isoxidised by a two-electron oxidising agent to the corresponding terephthalato-cobalt(m) complex but a one-electron oxidising agent leads to reduction ofthe cobalt (1x1) Oxygen tracer studies show complete oxygen transferfrom [(NH3),CoOHJ3+ to Cr2+ when reduction takes place. When cis-[(NH,),CO(OM,),]~+ or ~is-[en,Co(OH,),]~+ (en = ethylenediamine) is re-duced, only one oxygen atom is transferred for each complex ion and thereis no evidence for a double oxygen bridge.42 The aquation of trans-s* C.K. Ingold, R. S. Nyholm, and M. L. Tobe, Nutuye, 1960, U7, 477.85 J. W. Palmer and F. Basolo, J . Phys. Chem., 1960, 64, 778; J . Inovg. NuclearChem., 1960, 15, 279.56 F. B. Baker, T. W. Newton, and M. Kahn, J . Phys. Chetn., 1960, 64, 109; S. W.Rabideau and R. J. Kline, ibid., p. 193; T. W. Newton and H. D. Cowan, ibid., p. 244;S. W. Rabideau, ibid., p. 1491; J. C. Sullivan, A. J. Zielen, and J. C. Hindman, J . Amey.Chem. SOC., 1960, 82, 5288.57 J. Y.-P. Tong and E. L. King, J . Amer. Chem. SOC., 1960, 82, 3806.38 A. W. Adamson, J . Inoyg. NucEeav Chem., 1960, 13, 275.39 J.B. Hunt and J. E. Earley, J . Amer. Chem. SOC., 1960, 82, 5312.40 F. Basolo, J. W. Palmer, and R. G. Pearson, J . Anzer. Chem. Soc., 1960, 82,1073; R. G. Pearson, N. C. Stellwagen, and F. Basolo, ibid., p. 1077; R. G. Pearson,H. H. Schmidtke, and F. Basolo, ibid., p. 4434.41 P, Saffir and H. Taube, J . Amer. Chem. SOC., 1960, 82, 13; R. T. M. Fraser andH. Taube, ibid., p. 4152.42 W. Krnse and H. Taube, J . Amer. Chem. SOC., 1960, 82, 526142 INORGANIC CHEMISTRY.[Coen,(NH,)XI2+ (X = NO,-, C1-, Br-) leads initially to the tram-productwhich slowly isomerises to the cis-derivative in air. Aquation of cis-[Coen,(NCS)XJ+ (X = C1-, Br-) gives the cis-products whilst the trans-isomers give both cis- and trans-products. The great difference between therates of aquation of the cis- and trans-isomers is believed to originate from alone pair being fed in from the isothiocyanate group (+ T effect) in thecis-case, no such mechanism being possible in the trans-case.& Cobalt (111)complexes always contain some cobalt (11) after treatment with activatedcharcoal and it is suggested that reactions such as the racemisation of thetrisethylenediaminecobalt (111) ion which appear to be catalysed by activatedcharcoal are, in fact, catalysed by the cobalt(I1) produced by the activatedcharcoal.44 The rate of chloride-ion exchange with trans-Pt py2C1,] (py =pyridine) in a variety of solvents depends markedly upon the properties ofthe solvent, showing that there is strong interaction between the solvent andthe metal in the rate-determining step.45(c) Carbonyls.The properties of anionic carbonyls have been reviewed.4GA new carbonyl (vanadium hexacarbonyl), V(CO),, results from the reductionof vanadium compounds in a metal-amine system in the presence of carbonmonoxide or by the action of carbon monoxide on ditoluenevanadium(0).It is almost certainly a paramagnetic monomer in the solid state but theremay be dimerisation in solution. It is an air-sensitive, blue-green com-pound, and is easily reduced to the [v(co)G]- anion.47 Chromium hexa-I0Simplified model of Co,(CO),, viewed down threefold axis.Co atom further bonded to 3CO groups.Co atom further bonded to 2CO groups.carbonyl can be synthesised by the action of carbon monoxide on chromicchloride, aluminium, aluminium chloride, and benzene-a mixture which,in the absence of carbon monoxide, would produce diben~enechrornium.~~Tetracobalt dodecacarbonyl has a structure (6) in which the four cobaltatoms are at the corners of a tetrahedron, and one cobalt is further joined tothree carbonyl groups; the other cobalt atoms are linked to each other by43 M.L. Tobe, J., 1959, 3776; M. E. Baldwin and M. L. Tobe, J., 1960, 4275.44 F, P. Dwyer and A. M. Sargeson, Nature, 1960, 187, 1022.P5 R. G. Pearson, H. B. Gray, and F. Basolo, J . Amer. Chem. Soc., 1960, 82, 787.46 W. Hieber, W. Beck, and G. Braun, Angew. Chem., 1960, 72, 795.47 R. L. Pruett and J. E. Wyman, Chem. and I d , 1960, 119; G. Natta, R. Ercoli,F. Calderazzo, A.Alberola, P. Corradini, and G. Allegra, Atti Accad. naz. Lincei, Rend.Classe Sci. fis. mat. nut., 1959, 27, 107; R. Ercoli, F. Calderazzo, and A. Alberola,J . Amer. Ckcenz. Soc., 1960, 82, 2966; I;. Calderazzo, R. Cini, P. Corradini, R. Ercoli,and G. Natta, Cheun. and I d . , 1960, 500:.48 E. 0. Fischer, W. Hafner, and K. Ofele, Chent. Ber., 1959, 92, 3050SHARP : THE TRANSITION ELEMENTS. 143carbonyl bridges and are further each joined to two free carbonyl groups.49Iron pentacarbonyl and dicobalt octacarbonyl interact in acetone to giveC~~I(acetone)~ [FeCo,(CO),,], a salt in which the anion probably has astructure similar to that of CO,(CO),,.~~Hydrocarbon-metal carbonyls have been excellently reviewedin a lecture.51 Substituted carbonyls can be prepared by dissolvingphosphine and arsine complexes of metal halides in ethanolic alkali.[Ru,Cl,(PEt,Ph),]Cl gives [RuHCl(CO) (PEt,Ph),] which can be convertedinto [RuCl,(CO) (PEt,Ph),] with hydrogen chloride; [RhCl,(PEt,),] gives[RhCl(CO)(PEt,),]. Ally1 alcohol does not require the presence of a baseand [RhCl,(PEt,Ph),] can be converted into [RhCl(CO) (PEt,Ph),] .52 Al-though trans-[RhCl(CO) (PArJ,] complexes are very stable and inert,carbonyl and chloride exchanges with these complexes are very rapid.53Metal carbonyl fluorides, PtF,(CO), and RhF,(CO),, have been prepared bythe action of carbon monoxide on the appropriate metal tetrafluorides.These are the first metal carbonyl fluorides and are notable for the highoxidation states of the metals as compared with other carbonyl halides.=Photochemical initiation is a good method for preparing substitutedmetal carbonyls.Examples of complexes prepared by this method andalso by more normal substitution methods are : Cr(CO),py, Cr(CO),aniline,x-CpMn(CO),py (Cp = C5H,), Ifiln,(CO),[C,H,*PPh], [Re(CO),PPh,],,[Co(CO),(PR,) J +, and [CO(CO),(PR,)],.~~ Diethylene glycol dimethyl ether(diglyme) reacts with molybdenum hexacarbonyl to give diglyme-Mo(CO),.The ether is displaced by most other ligands and it is possible that thiscomplex is an intermediate when diethylene glycol dimethyl ether is usedas a solvent in the preparation of substituted ~arbonyls.~~ Metal hexa-carbonyls react with o-phenylenebisdimethylarsine (D) to give MD(CO),and MD,(CO), derivatives.The molybdenum complexes are oxidised byhalogens to give derivatives of the types MoD(CO),X,, [MoD,(CO),X] +X-,and MoDBr,, some of which are formulated to contain seven-co-ordinatem~lybdenurn.~~ Sulphur-containing ligands such as Me,S, [CH&> S,and (H,N),C=S can displace cycloheptatriene from C,H,Mo(CO), to givesulphur complexes.58 Na,[Cr-II(CO),] reacts with aqueous sodium cyanideto give Na[CrO(CO),CN] and N~,[CI!(CO)~(CN),] .59 Various salts of the[M*(CO),I]- anions may be prepared by heating the appropriate iodide withhexacarbonyls in diglyme. Pyrolysis of N-methylpyridiniurn iodopen ta-carbonylchromate(0) gives the arene complex tricarbonyl-C-methylpyridine-Cr(C0)5(RCN), Mo(C0)5py, Mo(C0)4py2, 1v(c0)5Py, kvfC0)4py2~49 P.Corradini, J . Chem. Phys., 1959, 31, 1676.P. Chini, L. Colli, and M. Peraldo, Gazzetta, 1960, 90, 1005.51 P. L. Pauson, Proc. Chem. Soc., 1960, 297.52 J. Chatt and B. L. Shaw, Chem. and I n d . , 1960, 931.53 EI. B. Gray and A. TVojcicki, Proc. Chem. Soc., 1960, 358.54 D. W. A. Sharp, Proc. Chem. Soc., 1960, 317.55 W. Strohmeier and K. Gerlach, Z. Naturforsch., 1960, 15b, 413, 622, 675; W.Strohmeier, K. Gerlach, and G. Matthias, ibid., p. 621 ; W. Strohmeier and K. Gerlach,Chem. Rev., 1960, 93, 2087; W. Hieber and W. Freyer, ibid., p. 462.56 K. P. M. Werner and T. H. Coffield, Chem. and I*zd., 1960, 936.57 H. 1;. Nigam, R. S. Nyholm, and Bl. H. B. Stiddard, J . , 1960, 1803, 1806.s x F. A. Cotton and F. Zingales, Chem. and Ind., 1960, 1210.js H.Behrens and J. Kohler, 2. anorg. Chem., 1960, 306, 94144 INORGANIC CHEMISTRY.chromium(0) .60 Manganese carbonyl reacts with pyridine to giveiMn1Ipy6 [Mn-I (CO),] , ; o-phenanthr oline gives (OC),Mn*Mn (CO),phen whichis broken down to phenMn(CO), by ultraviolet radiation.61 The phosphinecomplexes Mn(CO),PR, are reduced by sodium in tetrahydrofuran togive Na[Mn-I(CO),PR,] salts; these form the organometallic derivative,MeMn(C0)4PR, , with methyl iodide.62 Rhenium complexes , Re(PR,),(CO),X ,react with P-tolyl isocyanide (L) to give mixed carbonyl isocyanidesRe( PR3),(C0) LX and Re(PR,),(CO)L,X. Carbonyls of dipositive rhenium,Re(PR,)(CO)X,, can be prepared by the action of carbon monoxide onRe(PR,),X,; the action of isocyanide on this last complex gives salts con-taining the [Re(PR,),LX]+ cations.63 Other isocyanide complexes,RFe(CO),, have been prepared by the direct reaction between iron penta-carbonyl and the isocyanides Me,SiNC and Me,GeNC.@J p-Di-iminodi-iron-hexacarbonyl is formed by the action of sodium nitrite on tri-irondodecacarbonyl; the reaction appears to proceed by the interaction ofthe [Fe3(C0)ll]2- ion and hydr~xylamine.~~ The compounds [Fe(CO),X],[X = S, Se, SEt, SeEt] are dimers with chalcogen bridgesM Further substi-tution into the iridium carbonyl halides can be effected by reaction of amines,phosphines, and arsines with the complexes KIr(CO),X4, K21r,(CO),X,, and .Ir(CO),X.6' The product of the reaction between o-phenanthroline andnickel carbonyl has been reformulated as NiI'phen,[Ni,-'(CO),] ; pyridinereacts similarly and, after being made first alkaline and then re-acidified withacetic acid, salts of the [Ni,(CO),H]- and [Ni,(CO),I2- anions can be pre-pared. Na,[Ni,(CO)$ results from the direct reduction of nickel carbonylwith sodium in liquid ammonia.Another complex nickel carbonyl anion,[Ni3(CO)s]2-, has been postulated as the source of carbon monoxide in thereaction in which diphenylacetylene is carbonylated to trans-lxpdiphenyl-acrylic acid under alkaline conditions.68(d) Nitrosyls. Trinitrosylcarbonylmanganese, Mn(NO),CO, a memberof the series Ni(CO),, Co(CO),NO, Fe(CO),(NO)z, can be prepared as greencrystals by the action of nitric oxide on manganese carbonyl iodide at90-100".Treatment of (Ph,P)Mn(CO),I with nitric oxide gives(PkP) Mn (NO) , whilst ( Ph,P) Mn (CO) , gives (Ph,P) Mn (CO) ,NO ,69 Thefirst nitrosyl compound of rhenium, probably Ag,[Re(CN),NO], was isolatedafter interaction of K,Re(CN), and nitric acid.?* Sodium amalgam reducesan ethanolic or tetrahydrofuran solution of dinitrosyldicarbonyliron to the60 E. W. Abel, MI. A. Bennett, and G. Wilkinson, C h m . and Ind., 1960, 442; E. 0.61 W. Hieber and W. Schropp, jun., 2. Naturforsch., 1960, 15b, 271.82 W. Hieber, G. Faulhaber, and F. Theubert, 2. Naturforsch., 1960, 15b, 326.63 M. Freni and V. Valenti, Gazzetta, 1960, 90, 1430, 1445.64 D. Seyferth and N. Kahlen, J . Amer. Chem. Soc., 1960, 82, 1080.65 W. Hieber and H. Beutner, 2. Naturforsch., 1980, 15b, 324.66 W.Hieber and W. Beck, 2. anorg. Chem., 1960, 805, 265; cf. S. F. A. Kettle andL. E. Orgel, J., 1960, 3890.67 M. Angoletta, Gazzetta, 1959, 89, 2359; 1960, M, 1021.68 W. Hieber, W. Kroder, and E. Zahn, 2. Naturforsch., 1960, lsb, 325; €3. W.Sternberg, R. Markby, and I. Wender, J . Amer. Chem. SOL, 1960, 82, 3638.69 C . G. Barraclough and j. Lewis, J., 1960, 4842; W. Hieber, W. Beck, and H.Tengler, 2. Nutuufovsch., 1960, 15b, 411; R. F. Larnbert and J. D. Johnston, Chem.and Ind., 1960, 1267.7o R. Colton, R. D. Peacock, and G. Wilkinson, J., 1960, 1374.Fischer and K. Ofele, Chem. Bey., 1960, 98, 1156SHARP: THE TRANSITION ELEMENTS. 145[Fe(CO),NO]- anion, and various salts can be isolated from s a l ~ t i o n . ~ ~ Thedimers [Fe(NO),SEt],, [Fe (NO),SeEt],, [Co (NO) 2Cl]2, and [Co(NO),Br], arenon-polar and probably have chalcogen or halogen bridges similar to thosepostulated for the corresponding iron carbonyl derivative^.^, A spectro-scopic study of the red form of nitrosopentamminecobalt (111) salts suggeststhat these unimolecular complexes have the nitrosyl group co-ordinated tothe cobalt through the oxygen atom; this is the first time that this type ofco-ordination has been postulated for the nitrosyl or carbonyl groups.73 Astable nickel nitrosyl, (Ph,P),Ni(NO)Br, can be prepared by the action ofsodium nitrite on (Ph,P),NiBr, in tetrahydr~furan.'~ Palladous chloridereacts with nitric oxide in the presence of water to give Pd(N0)Cl which,like Pd(NO),Cl,, presumably contains palladium(0) .75 Solutions of cuprichalides, including the fluoride, in higher alcohols absorb nitric oxide to givedeep-blue nitrosyl complexes which are stable only in solution.76Further and more precise physical studies havebeen made on olefin complexes; in general, authors are in favour of thebonding being by overlap of the x orbital of the olefin with the d orbitals ofthe metal rather than by 0 bonds from the carbon atoms to the metal.Thestructure of trans-[(C,H,)Pt(NHMe,)CIJ is in agreement with thisThe only new ethylene complex reported is x-CpMn(C,H,) (CO),, an orange-red, light-sensitive compound which results from the action of ethylene onx-cyclopentadienylmanganese tricarb~nyl.~~ Bisacraldehydenickel(0) is simi-lar to bisacrylonitrilenickel(0); the latter complex has now been shown toform 1 : 1 and 1 : 2 adducts with triphenylphosphine.Acrylonitrileirontetracarbonyl has been obtained in low yield by the reaction betweenacrylonitrile and tri-iron dodeca~arbonyl.'~ A brief review has been pub-lished on the carbonylation of norbornadiene with metal carbonyls, a re-action with proceeds by way of diene-metal complexes.80 Many more com-plexes of such dienes as butadiene, cyclohexa-l,3-diene, norbornadiene ,bicyclo [2,2,1] hept a-2,5-diene, cyclo-oct a- 1,5-diene, and spiro [4,4]nona-1,3-diene with vanadium , chromium, molybdenum, manganese, iron,cobalt, palladium, platinum, and mercury have been described.81p82J@(e) OZe& complexes.71 W. Hieber and K.Beutner, 2. Naturforsch., 1960, 15b, 323.72 W. Hieber and W. Beck, Z. anorg. Chem., 1960, 305, 274.53 S. Yamada, H. Nishikawa, and R. Tsuchida, Bull. Chem. Sor. Japan, 1960, 33,74 R. D. Feltham, J . Inorg. Nuclear Chem., 1960, 14, 307.55 J. Smidt and R. Jira, Chem. Ber., 1960, 93, 162.713 R. T. M. Fraser and W. E. Dasent, J . Amer. Chenz. SOC., 1960, 82, 348; R. T. M.Fraser, Nature, 1960, 188, 738.77 D. M. Adams and J. Chatt, Chem. and Ind., 1960, 149; D. B. Powell and N.Sheppard, J., 1960, 2519; P. R. H. Alderman, P. G. Owston, and J. M. Rowe, A d aCryst., 1960, 13, 149.78 H. P. Kogler and E. 0. Fischer, 2. Natztrforsch., 1960, 15b, 676.79 G. N. Schrauzer, J . Amer. Chem. SOL, 1960, 82, 1008; S. F. A. Kettle and L. E.80 C. W. Bird, R.C. Cookson, and J. Hudec, Chew. and Ind., 1960, 20.81 E. 0. Fischer and W. Frohlich, 2. Naturforsch., 1960, 15b, 266; E. 0. Fischer,H. P. Kogler, and P. Kuzel, Chenz. Ber., 1960,93, 3006; G. Winkhaus and G. Wilkinson,Chem. and Iwd., 1960, 1083; R. A. Alexander, N. C . Baenziger, C. Carpenter, and J. R.Doyle, J . Amer. Chem. SOC., 1960, 82, 535.930.Orgel, Chem. and I n d . , 1960, 49.82 A. Nakamura and N. Hagihara, J . Chem, SOC. Japan, 1960, 81, 1072.83 T. A. Manuel and F. G. A. Stone, J . Amer. Chem. SOC., 1960, 82, 366146 ~NORGANIC; CHEMISTRY.Dipentene (7) gives dipenteneiron tricarbonyl when treated with tri-irondodecacarbonyl but reacts with molybdenum and tungsten hexacarbonylsin the form of its isomer 9-cymene (8) to give x-$-cymene-metal tri-carbonyls.s4 The double bonds in a diplefin can be separated by a hetero-atom and still give diolefin complexes. Dimethyldivinylsilane reacts withMe M eCHMetungsten and molybdenum carbonyls to give dimethyldivinylsilylmetaltetracarbonyls.However, iron pentacarbonyl cleaves the vinyl groupsfrom dialkyldivinyltins and [R,SnFe(CO)J, dimers result .849g5Several new cyclopentadiene complexes have been described. Re-duction of arene-x-cyclopentadienyliron iodides with lithium aluminiumhydride gives arenecyclopentadieneiron derivatives. These react with acidto give arene-x-cyclopentadienyliron cations.86 Di-x-cyclopentadienyl-chromium reacts with carbon monoxide and hydrogen under pressure togive tricarbonyl-x-cyclopentadienylchromiurn hydride and cyclopentadiene-chromium(0) dicarb~nyl.~~ The product, C,H,,Fe(CO),, from the reactionof a mixture of cyclo-octatrienes with iron pentacarbonyl is considered to bebicyclo[4,2,0]octa-2,4-dieneiron t r i c a r b ~ n y l .~ ~ * ~ ~ x-Cyclopentadienylcobaltdicarbon yl reacts with c yclo-oc t at et raene to give c yclo-oct atetraene-x-cyclo-pentadienylc~balt.~~ The olefin in this complex has three proton peaks inits nuclear magnetic resonance spectrum and is presumably present in thetub form. Iron pentacarbonyl gives C,H,Fe(CO),, C8H8~e(CO)3]2, andC8H,Fe,(CO), when treated with cyclo-octatraene.82Jm C,H,Fe(CO), isdifficult to hydrogenate and has only one proton peak in its nuclear magneticresonance s p e c t r ~ m . ~ ~ * ~ ~ The structure has been discussed in terms ofx-bonding from a planar conjugated eight-membered ring but it is possiblethat interconversion of non-planar structures would give a single resonanceline for the protons in the complex.g0 Cyclo-octatetraeneiron tricarbonylreacts with triphenylphosphine to give (Ph,P),Fe(CO), but triphenyl-arsineand -stibine give the olefin complexes (Ph3M) (C,H,)Fe(CO),.The olefingroups in C,H,,Fe(CO), and butadieneiron tricarbonyl appear to be bondeddifferently and both react with triphenylphosphine with eliminationof olefin to form (Ph,P)3Fe(C0),.83 Cyclononatetraenemolybdenum tri-carbonyl is formed when bicycIo[4,3,0]nonatriene reacts with molybdenumhexacarbonyl. One of the double bonds in the tetraene complex is easilyhydrogenated and appears not to take part in the bonding to the metaLgl84 T.A. Manuel and F. G. A. Stone, Claem. and Ind., 1960, 231.85 R. B. King and F. G. A. Stone, J . Amer. Chem. SOC., 1960, 82, 3833.86 M. L. H. Green, L. Pratt, and G. Wilkinson, J., 1960, 989.87 E. 0. Fischer and K. Ulm, 2. Nnturforsch., 1960, 15b, 59.88 E. 0. Fischer, C. Palm, and H. P. Fritz, Chem. Ber., 1959, 92, 2645; E. 0. Fischerand C. Palm, 2. Naburforsch., 1959, 14b. 598.89 A. Makamura and N. Hagihara, Bull. Chein. SOC. Japan, 1960, 33, 425.90 F. A. Cotton, J., 1960, 400; A. Nakamura and N. Hagihara, Mem. Inst. Sci. andInd. Res., Osaka Univ., 1960, 17, 187.91 R. B. King and F. G. A. Stone, J . ,4mer. Chem. Soc., 1960,82, 4557SHARP : THE TRANSITION ELEMENTS. 147Cyclohexa-l,3-diene reacts with manganese carbonyl to give x-cyclohexa-dienylmanganese tricarbonyl (9) in which the bonding is similar to thatobserved in cyclopentadiene complexes.This compound may also be pre-pared by reduction of the tricarbonyl-lt-benzenemanganese(1) cation,[C,H,Mn(CO),]+, with sodium borohydride; tricarbonyl-~c-cyclohexadienyl-iron fluoroborate, in which the cation is isoelectronic with the manganesecompound mentioned above, results by hydrogen abstraction from cyclo-hexadieneiron tricarbonyl with triphenylmethyl A~oroborate.~~ There hasbeen considerable interest in the “ sandwich ” compounds formed by con-j ugated aliphatic unsaturated systems. Ally1 bromide reacts with sodiumtetracarbonylcobaltate(-I) to give GH,Co(CO), and with sodium penta-carbonylmanganate(-I) to give C,H5Mn(C0)5.93 A similar palladium deriv-ative, [C,H,PdCl],, has been prepared by the reaction between allyl chlorideor allyl alcohol and palladium chloridcg4 Spectroscopic data have beeninterpreted in favour of structure (lo), the allyl group acting as a discreteunsaturated entity, although a structure involving both a 0 and a x bond isnot completely ruled o ~ t .~ ~ * ~ ~ It is suggested that the two isomeric com-plexes, C,H,O,Co, obtained when buta-l,3-diene reacts with cobalt carbonylhydride, are substituted allyl derivatives (11) and (12) with the methylY HIgroup in the eizdo- and exo-positi~ns.~~ The allyl-metal complex forms afairly stable entity and allylpalladium chloride reacts with sodium cyclo-pentadienide to give allyl-x-cyclopentadienylpalladium(~~) .97( f ) Acetylene complexes and reactions of transition-metal compounds withacetylenes. Perfluorobut-2-yne gives complexes with transition metals ;the structures appear to be similar to those of hydrocarbon acetylene-metalcomple~es.~~ Alkyl- and aryl-chromiums and diethylnickel normally poly-inerise substituted acetylenes to substituted benzene derivatives via acetylene92 G.Winkhaus and G. Wilkinson, Proc. Chem. SOC., 1960, 311; E. 0. Fischer andR. D. Fischer, Atzgew. Chem., 1960, 72, 919.83 R. F. Heck and D. S. Breslow, J . Amer. Chem. Soc., 1960, 82, 750; H. D. Kaesz,R. 13. King, and F. G. A. Stone, 2. Naturforsch., 1960, 15b, 682.94 J. Smidt and W. Hafner, Angew.Chem., 1959, 71, 284; R. Hiittel and J. Kratzer,ibid., p. 456; I. I. Moiseev, E. A. Federovskaya, and Y . K. Syrkin, Zhur. neorg. Khim.,1959, 4, 2461 [1218].95 H. C. Dchm and J . C. W. Chien, J . Amer. Chenz. SOC., 1960, 82, 4429.g6 C. L. Aldridge, H. R. Jonassen, and E. Pulkkinen, Chern. and I n d . , 1960, 374;1). 11‘. Moore, H. B. Jonassen, T. B. Joyner, and A . J. Bertrand, ibid., p. 1304.07 B. I.. Shaw, Pyoc. Client. SOC., 1960, 247.s8 J . I,. Boston, D. \V. A. Sharp, and G. \C’ilkinson, C‘hcm. and Iizd., 1960, 1137148 INORGANIC CHEMISTRY.complexes. However, triethylchromium can contribute a C , fragment tothe polymerisation product (e.g., tolane gives 1,2,3,4-tetraphenylbenzene) ortrimethylchromium can contribute a C, fragment (e.g., tolane gives 1,2,3,4-tetraphenylcyclopentadiene) .99 Acetylene reacts with manganese carbonylto give x-dihydropentalenylmanganese tricarbonyl(l3) which can be reduced(13)to x-tetrahydropentalenylmanganese tricarbonyl (14), a complex which canalso be prepared by the action of cyclo-octatetraene on manganesecarbonyl.In this latter reaction the cyclo-octatetraene is acting as a bi-cyclo[3,3,0]octane derivative.loO Rhenium trichloride and triphenyl-phosphinerhenium( 111) chloride give acetylene complexes by direct reaction ;some rhenium-olefin complexes with dicyclopentadiene have also beendescribed.lol The compounds isolated by Reppe from the reaction betweeniron carbonyl and acetylene have been re-investigated. Acetylene reactswith iron pentacarbonyl in petrol or benzene to give x-cyclopentadienoneirontricarbonyl.The cyclopentadienone portion of the complex is stronglybasic and forms a hydriodide and a hydrogen-bonded adduct with quinol-an adduct which can also be obtained by the reaction between acetylene andiron pentacarbonyl in aqueous ethanol. On oxidation, cyclopentadienone-iron tricarbonyl is converted into the dimer of cyclopentadienoneiron di-carbony1.lO2 The complexes H*Co,(CO),C,HR which result from the actionof acids on acetylenedicobalt hexacarbonylcomplexes can also be prepared by the inter-action of dicobalt octacarbonyl and, e.g.,studies suggest structure (15) for these com- \ I/ (,5) plexes.lo3 Palladous halides react with acetyl-( W 3 enes (ac) to give the complexes Pd(ac),X,,[Pd(ac),X],, and Pd(ac),X.The structures ofthese complexes are not known but a cyclobutadiene ring may be present inthe first.104 Copper and silver alkyl- and aryl-ethynyl compounds areregarded as co-ordination polymers (16). Donor molecules break down thepolymeric structures to dimers (17) or trimers; the copper compounds formphosphine adducts by direct reaction and ammines by preparation in liquidammonia; the silver compounds form phosphine and amine adducts bydirect reaction.lo509 M. Tsutsui and H. Zeiss, J . Amer. Chem. SOL, 1959, 81, 6090; W. Herwig, W.Metlesics, and H. Zeiss, ibid., p. 6203.100 T. H. Coffield, K. G. Ihrman, and W. Burns, J . Amer. Chem. Soc., 1960, 82,4209.101 R. Colton, R. Levitus, and G.Wilkinson, Nature, 1960, 186, 233.108 E. Weiss, R. G. MerCnyi, and W. Hiibel, Chern. and Id., 1960, 407; cf. ref. 86.103 W. Hiibel and C. Hoogzand, Chem. Ber., 1960,93, 103; U. Kriierke and W. HiibeI,104 L. Malatesta, G. Santarella, L. Vallarino, and F. Zingales, Atti Accad. naz. Lincei,105 D. Blake, G. Calvin, and G. E. Coates, Proc. Chem. Soc., 1959, 396; cf. R. NastH ' 0R ($? 1 3(CO),C0 ' .---- ---- c/" t i phenylacetylenecarboxylic acid. DegradativecoChem. and Ind., 1960, 1264.Rend. Classe S c i . 3 ~ . mat. nut., 1959, 27, 230; Angew. Chem., 1960, 72, 34.and W. Pfab, Chem. Bey., 1956, 89, 416SHARP : THE TRANSITION ELEMENTS. 149Crystal-structure determinationshave confirmed the presence of cyclobutadiene ring systems in the com-plexes Fe(CO),(PhCECPh), and NiC12C8H12.10B Tricyclopentadienyltitaniumis a green paramagnetic complex prepared by the action of excess of sodium(g) Complexes with aromatic systems.r! / Ph r-cyclopentadienide on dicyclopentadienyltitanium dichloride ; it gives dicyclo-pentadienyltitanium dicarbonyl with carbon monoxide.lo7 Dicyclopenta-dienyltitanium(II1) derivatives can be prepared by the reaction Cp2TiC1, +LiBH, + Cp2TiBH4.The tetrahydroborate reacts with halogen deriv-atives to give dicyclopentadienyltitanium(II1) halides.1°8 Cyclopentadienyl-titanium trichloride, described last year, can also be prepared by the actionof titanium tetrachloride or chlorine on dicyclopentadienyltitanium dichlor-ide.lm Halogens oxidise cyclopentadienylvanadium tetracarbonyl to CpVC1,(violet) or CpVBr, (green).Blue dicyclopentadienylvanadium(II1) chloride,Cp2VC1, is prepared by the action of sodium cyclopentadienide on vanadiumtrichloride ,110 by the action of hydrogen chloride on phenyldi-lc-cyclopent a-dienylvanadium , or by interaction of dicyclopentadienylvanadium(1v)chloride and dicyclopentadienylvanadium.ll1 Dicyclopentadienylchromiumis oxidised by oxygen to give [CpCrO],, a tetramer which is formulated withan eight-membered ring of alternate chromium and oxygen atoms.ll2 Iodinecleaves the metal-metal bonds in [x-CpMo(CO),], and [x-CpW(CO),], to givethe corresponding iodides. The reaction x-CpMo(CO),Na + x-CpW(CO),I__t ~C-C~MO(CO),=W(CO)~(X--C~) gives a compound with a metal-metal bondbetween two different transition metals.l13 More details have now beengiven of the preparation and properties of metal-azulene complexes.Thereaction between azulenes (az) and metal carbonyls gives complexes of thotypes azFe,(CO),, azFe,(CO),,, azMn,(CO),, and azMo,(CO),. The metalatoms appear to be cis with respect to the planar hydrocarbon and the com-plexes have shown up a novel type of isomerism associated with the positionsof the double bonds in the complexes derived from unsymmetrically sub-stituted a~u1enes.l~~ A three-dimensional X-ray study of dibenzene-chromium shows that, although the rings are planar, the C-C bonds havelo6 R. P. Dodge and V. Schomaker, Nature, 1960, 186, 798; J. D. Dunitz, H. C.Mez, and H. M. M. Shearer, XVIIth Internat. Congr.Pure Appl. Chem., 1959, abs. A164.lo' E. 0. Fischer and A. Lochner, 2. Natwforsch., 1960, 15b, 266.l08 H. Noth and R. Hartwimmer, Chem. Ber., 1960, 93, 2238, 2246.109 R. D. Gorsich. J , Amer. Chem. SOL, 1960, 82, 4211.ll0 E. 0. Fischer, S. Vigoureux, and P. Kuzel, Chem. Ber., 1960, 93, 701.111 €3. J. de Liefde Meijer, M. J. Janssen, and G. J. M. van der Kerk, Chem. and Id.,112 E. 0. Fischer, K. Ulm, and H. P. Fritz, Chem. Ber., 1960, 93, 2167.113 E. W. Abel, Apar Singh, and G. Wilkinson, J., 1960, 1321.114 R. Burton, L. Pratt, and G. Wilkinson, J., 1960, 4290.1960, 119160 INORGANIC CHEMISTRY.lengths 1.45 and 1.36 A alternating around the ring. Previous structuraldeterminations on ferrocene and ruthenocene have indicated some alternationin bond lengths but the differences have only been of the same order ofmagnitude as the expected errors and have not been considered ~ignificant.11~Diphenylbis(tricarbony1chromium) has the two phenyl groups co-planar,the chromium atoms being trans to each other.l16 Dibenzenetungsten is agreen sublimable solid prepared in a manner similar to that used for thepreparation of other diarenemetal complexes.It is oxidised by iodine tothe orange W(C,H,),]+ ~ati0n.l~' Complexes of the chromium tricarbonyland iron tricarbonyl groups with the condensedaromatic hydrocarbons thianaphthen, acenaph-thylene, pyrene, chrysene, and phenant hrene havebeen described. It seems that fusion of an extraring to the naphthalene system in a linear posi-tion leads to a marked reduction in the stabilityof the metal derivative^.^^,^^^ The [m,n]para-( I 8) cyclophanes (18) give tricarbonyl-chromiumadducts' when treated with chromium carbonyl.When m and n < 4 only monoderivatives are formed; bis-derivatives areformed when m = 4, n = 5, and m = n = 6.Bis-arene complexes couldnot be prepared.llgOrganometallic Compounds of the Transition Elements.-Methyl-lithiumreacts with x-cyclopentadienyltitanium trichloride to give x-cyclopenta-dienyltrimethyltitanium, a compound which is stable at -70" but decom-poses slowly at O0.l2O Black, unstable di-x-cyclopentadienylphenyl-vanadium(m), Cp2VPh, is formed by the action of phenyl-lithium on di-x-cyclopentadienylvanadium dichloride.lll Diphenylmercury reacts withvanadium oxytrichloride or tetrachloride to give solutions of phenyl-vanadium oxydichloride and phenylvanadium trichloride, respectively ; theorganometallic compounds were not actually isolated but identification wasbased on the stoicheiometry of the reaction.121 Organorhenium penta-carbonyls, RRe(CO), (R = Ph, CH2Ph, MeCO, and PhCO), are formed bythe action of organic halides on sodium pentacarbonylrhenate(-I) .I22 Manyrelatively stable organometallic derivatives of iron are now being prepared.Iron carbonyls desulphurise thiophen to give C1,H,06Fe, (19) containingFe-C Q bonds1= The compound previously formulated as a perfluoro-olefin complex of iron tricarbonyl is now considered to be (20).Di-cobalt octacarbonyl reacts with tetrafluoroethylene to give orange(OC),Co*CF,-CF,Co(CO), and di-x-cyclopentadienylcobalt reacts to give ap 71-0-J p,I] rn [CHl],115 F.Jellinek, Nature, 1960, 187, 871.116 P. Corradini and G. Allegra, J . Amer. Chem. Soc., 1960, 82, 2075.117 E. 0. Fischer, F. Scherer, and H. 0. Stahl, Chem. Ber., 1960, 93, 2065.118 E. 0. Fischer and N. Kriebitzsch, 2. Natzlrforsch., 1960,15b, 465; E. 0. Fischer,119 D. J. Cram and D. I. Wilkinson, J . Amer. Chem. Soc., 1960, 82, 5721.120 U. Giannini and S. Cesca, Tetrahedron Letters, 1960, No. 14, 19.121 W. L. Carrick, W. T. Reichle, F. Pennella, and J. J. Smith, J . Amer. Chem.122 W. Hieber, G. Braun, and W. Beck, Chem. Ber., 1960, 93, 901.123 H. D. Kaesz, R. B. King, T. A. Manuel, L. D. Nichols, and F. G, A. Stone,N.Kriebitzsch, and R. D. Fischer, Chem. Ber., 1959, 92, 3214.Soc., 1960, 82, 3887.,T. Amer. Chem. SOC., 1960, 82, 4749SHARP : THE TRANSITION ELEMENTS. 151x-cyclopentadienylcyclopentadiene complex, two cyclopentadiene groups in adinuclear molecule being linked by an ertdo-CF,*CF, bridge.124 Furtherderivatives which are related to those which occur as intermediates in the0x0 reaction have been isolated. Organometallic compounds, RCo(CO),(R = Me, Et, and CH,Ph), have been obtained by the reaction betweensodium tetracarbonylcobaltate(-I) and methyl iodide, Et,OBF,, and benzylbromide, respectively. The methyl derivative gives MeCOCo(CO), withcarbon monoxide; this acyl derivative is identical with that obtained fromacetyl bromide and sodium tetracarbonylcobaltate(-I) .125 Allylcobalttetracarbonyl reacts similarly but the acyl derivative is less stable.93 Acylderivatives of the transition metals are greatly stabilised in complexes withother ligands.Both alkyl- and acyl-cobalt carbonyls react with triphenyl-phosphine to give (tripheny1phosphine)acylcobalt tricarbonyls ; in the caseof the alkyl derivatives, carbonyl migration takes place ; carbon monoxideis evolved in the reaction with acyl derivatives. Alkylmanganese penta-carbonyls give similar derivatives, RCOMn(CO),*NHR'R'' in the presenceof secondary amines. Allylcobalt tricarbonyl reacts differently and gives(tripheny1phosphine)all ylcobalt (I) dicarbonyl.126 ' The complexes that resultfrom the reaction between cyclopropane and chloroplatinic acid have beenre-examined and are now formulated as polymers builttrans-isomer and to leave the organometallic group( 2 ' ) pane.127 The kinetics of the formation of methyl- andethyl-copper(1) by the interaction of copper nitrateand lead tetra-alkyls, and the kinetics of the subsequent decomposition ofthe organometallics, have been fully investigated.12* Phosphinegold halidesreact with Grignard reagents or organo-lithiums to give gold@) alkyls,R,PAuR', in which the organometallic is stabilised by the presence of thephosphine.lZ9 Cyclopentadienylethylzinc is unexpectedly formed by thereaction between cyclopentadienemagnesium bromide and zinc chloride inether.130 Two new methods for the synthesis of perfluoroalkylmercurialshave been described.Bispentafluoroethylmercury results from the reactionbetween mercuric fluoride and tetrafluoroethylene, and mercuric oxide andup from the unit (21). Pyridine reacts to form aintact, but tertiary phosphines liberate cyclopro-/TP ,'IHzC\cH/, 'a124 K. F. Watterson and G. Wilkinson, Chem. and Ind., 1960, 1358.125 D. S. Breslow and R. F. Heck, Chem. and Ind., 1960, 467.126 R. F. Heck and D. S. Breslow, J . Amer. Chem. SOC., 1960, 82, 4438; K. A.127 D. M. Adams, J. Chatt, R. G. Guy, and N. Sheppard, Proc. Chem. SOC., 1960,179.128 C. E. H. Bawn and F. J. Whitby, J., 1960,3926; C. E. H. Bawn and R. Johnson,129 G. Calvin, G. E. Coates, and P. S . Dixon, Chem. and Ind., 1959, 1628.130 W. Strohmeier and H. Landsfeld, 2. Nalwforsch., 1960, lfib, 332.Keblys and A.H. Filbey, ibid., p. 4204.J., 1960, 4162152 INORGANIC CHEMISTRY.tristrifluoromethylphosphine react to give bistrifluoromethylmercury.~31Bis(trifluoromethy1thio)mercury reacts with halide ions to give anionic com-plexes; this behaviour is similar to that observed with the perfluoroalkyl-mercurial^.^^^Molecular Hydrides of the Transition Elements.-The hydrides of thetransition elements have been reviewed during the year1= and it is nowapparent that metal-hydrogen linkages are much more common than waspreviously thought. A characteristic of compounds containing metal-hydrogen bonds is the high-field shift observed for the protons by nuclearmagnetic resonance spectroscopy. This technique has shown that borontrifluoride monohydrate protonates the metal atoms in metallocenes andthat many carbonyls and phosphinemetal carbonyls are protonated whendissolved in sulphuric or trifluoroacetic acids or in boron trifluoride mono-h~drate.1~4 Hydride species have now been established for the metals oftransition Groups V to IX.Sodium borohydride reduces a tetrahydrofuransolution of di-x-cyclopentadienyltantalum trichloride to the correspondingtrihydride ; the previously reported di-Tc-cyclopentadienylmetal dihydridesof molybdenum and tungsten can also be prepared by the action of a largeexcess of sodium cyclopentadienide on the highest chlorides. The cyclo-pentadienyl rings in these compounds are assumed to be at an angle to eachother; this arrangement leaves three orbitals available for bonding tohydrogen or for occupation by lone pairs of electrons.As expected, thetantalum hydride is non-basic but the molybdenum and tungsten com-pounds can be protonated to give the cations [Cp2MH3]+. Protonation ofCp,ReH and Cp,Fe does not completely utilise the available lone pairs be-cause of electrostatic consideration^.^^^ A mixture of a transition-metalhalide, a substituted phosphine or arsine, alkali, and ethanol gives hydridesor carbonyl hydrides. Typical reactions are : Pt(PEt3),C1, -+ trans-[Pt (PEt,) ,H*Cl] ; Thelatter compound gives Ru(PEt,Ph),Cl,(CO) with hydrogen chloride; ethan-olic potassium hydroxide reconverts this into the carbonyl hydride.52Another reaction which has now been recognised to result in the preparationof hydride species is the reduction of rhodium trichloride with hypo-phosphorous acid in the presence of methyldiphenylarsine. The products,[RhX2-H(AsPh2Me),], were previously formulated as dimeric complexes ofrhodium(11) .I36 Some new iron hydrides, trans-[FeH*X(diphosphine),]-(X = H or Cl) have been described.The dihydride is obtained by dissolvingiron in the diphosphine under an atmosphere of hydrogen; it can also beobtained, as can the hydrido-chlorides, by reduction of the appropriatechlorides with lithium aluminium hydride. tra~zs-(OsH*C1[C,H,(PEt2)&)[Ru,(PE t ,Ph),C13] C1 __t [Ru (PEt,Ph) ,H*Cl (CO)] .131 C. G. Krespan, J . Org. Chem., 1960, 25, 105; J. E. Griffiths and A. B. Burg,132 F. Jellinek and J. J.Lagowski, J., 1960, 810.133 M. L. H. Green, Angew. Chem., 1960, 72, 719.134 A. Davison and G. Wilkinson, Proc. Chew. Soc., 1960, 356; T. J. Curphey,J. 0. Santer, M. Rosenblum, and J. H. Richards, J . Amer. Chem. SOC., 1960, 82, 6249.136 E. 0. Fischer and Y. Hristidu, 2. Nutwforsch., 1960, 15b, 135; H. P. Fritz,Y. Hristidu, H. Hummel, and R. Schneider, ibid., p. 419; J. A. McCleverty and G.Wilkinson, Chern. and Ind., 1961, 288; cf. ref. 138.138 J. Lewis, R. S . Nyholm, and G. K. N. Reddy, Chem. and Id., 1960, 1386.J . Amev. Chem. SOC., 1960, 82, 5759SHARP: THE TRANSITION ELEMENTS. 153was also prepared by the latter method, and hydrides of this type are nowknown for all three elements of the iron gr0up.~3' Sodium borohydridereduces the complexes (R,P),NiX2 to hydride species which are stable onlyin s01ution.l~~ An X-ray study on PtHBr(PEt,), has confirmed the trans-structure for this complex although the hydrogen was notThe Scandium Group and the Lanthanides.-Reviews have been publishedthis year on the rare-earth hydrides140 and on the so-called anomalousoxidation states of the lanthanide and actinide elements.la La, Ce, Pr,and Nd form disulphides whilst Y, Gd, and Dy form sulphides of the formulaMzS380. Oxides and selenides interact to give oxyselenides, M,O,Se (M = Y,La, Ce, Pr, Nd, Sm, Gd, Dy, Er, and Yb).142 New hexaborides have beendescribed for Eu, Tb, and Tm.143 Graphite reduces samarium trifluoride tored brown SmFZ.lu Thulium di-iodide-a new oxidation state for thulium-is prepared by the action of thulium metal on mercuric iodide or thuliumtri-iodide.The Actinides.-The halides 146 and organic ligand complexes 14' of theactinides have been reviewed.Fusion of uranium dioxide in an argon arcat 2800" gives grey U02-% (0.15 > x > 0) and some metallic uranium.Stoicheiometric UO, is stable in hydrogen up to 1700".148 A preliminaryaccount of the structure of uranyl nitrate hexahydrate shows that the metalis eight-co-ordinate with two bidentate nitrate groups, two water molecules,and two oxygen atoms making up the co-ordination sphere. The uranylgroup is not linear; the 0-U-0 angle is 173°.14g The salt CS~(UO,)~(SO,),has a layer structure with [(U02)2(S04)3],2n- sheets; each uranyl ion isco-ordinated by five mono-dentate sulphate groups arranged in a pentagonnormal to the 0-U-0 axis.150 Uranium trioxide reacts with a mixture ofdinitrogen pentoxide and tetroxide to give the addition compoundU0,(N0,),,N,05.This decomposes on heating to give UO,(NO,),, a com-pound with interesting possibilities for its co-ordination polyhedron.151Anhydrous uranyl carbonate, U0,C03, can be prepared by oxidising uran-ium(1v) oxycarbonate followed by dehydration in vacuo; it is stable to500°.152 The main species which result from the hydrolysis of the uranylIn most air it gives the oxyhalide Tm0I.lgs137 J. Chatt, F. A. Hart, and R. G. Hayter, Nature, 1960, 187, 55.138 M. L, H. Green, C. N. Street, and G. Wilkinson, 2. Nuturforsch., 1959, 14b, 738.13s P. G. Owston, J.M. Partridge, and J. M. Rowe, Acta Cryst., 1960, 13, 246.140 V. I. Mikheeva and M. E. Kost, Uspekhi Khim., 1960, 55 [28].141 L. B. Asprey and B. B. Cunningham, Progr. Inorg. Chem., 1960, 2, 267.142 J. Flahaut, M. Guittard, and M. Patrie, Bull. Soc. chim. France, 1959, 1917;A. Benaceraff, M. Guittard, L. Domage, and J. Flahaut, ibid., p. 1920.143 N. N. Tvorogov, Zhur. neorg. Khim., 1959, 4, 1961 [890]; G. V. Samsonov, V. P.Dzeganovskii, and I. A. Semashko, Krystallografya, 1959, 4, 119 [log].144 A. D. Kirshenbaum and J. A. Cahill, J . Inorg. Nuclear Chem.. 1960, 14, 148.145 L. B. Asprey and F. H. Kruse, J . Inorg. Nuclear Chem., 1960, 13, 32.146 J. J. Katz and I. Sheft, Adv. Inorg. Chem. Radiochem., 1960, 2, 195.147 A. E. Comyns, Chew. Rev., 1960, 60, 115.148 J.S. Anderson, J. 0. Sawyer, H. W. Worner, G. M. WilIis, and M. J. Bannister,Nature, 1960, 185, 915; J. S. Anderson and J. 0. Sawyer, Proc. Chem. SOC., 1960;145.149 J. E. Fleming and H. Lynton, Chem. and Ind., 1960, 1415.150 M. Ross and H. T. Evans, jun., J . Inorg. Nuclear Chem., 1960, 15, 338.151 G. Gibson, C. D. Bientema, and J. J. Katz, J . Inorg. Nuclear Chem., 1960, 15,152 B. Sahoo and D. Patnaik, Nutwe, 1960, 185, 683; cf. J. Cejka, Chem. Listy,110.1960, 54, 124154 INORGANIC CHEMISTRY.ion in water are the polymeric ions [(U02),0HJ3+, [(U02)2(OH),J2+, and[(U0,),(OH)J2+ ; 153 spectrophotometric and solubility data have shown thatthe anionic species absorbed on ion-exchange resins from solutions containingnitrates have the formulz [Mm(NO,) J2- (M = Pu, Np, U, and T4.154Na3UF, reacts with elementary fluorine at 390" to give colourless N%UVF,.155Uranium tetra- and penta-chlorides, like most other transition-metalcklorides, form adducts with phosphorus pentachloride and phosphorylchloride.166 The phases PUB, PUB,, PUB,, and PUB, have been found inthe plutonium-boron system.157Titanium, Zirconium, and Hafnium.-Titanium(1v) is present in perchloricacid solutions in an equilibrium between the ions [Ti(OH),]+ and [Ti(OH),]2+;additional species, Ti(OH),HSO, and [Ti(OH),HSO,] +, are present in sul-phuric acid solutions.158 Potentiometric titrations on the Ti4+-F--H20system show that in acid solutions the ion containing most fluorine isTiOF,,-; this is in agreement with the results of studies on the hydrolysis ofthe hexafluorotitanate ion.159 K2Ti60,, the first hexatitanate, has beenestablished in the system K,O-TiO,; 160 the co-ordination polyhedron inK2Ti,05 is a slightly distorted trigonal bipyramid and the titanium is five-co-ordinate.161 It has been pointed out that the degree of polymerisationof the polymeric titanium alkoxides and halogenoalkoxides could possiblybe explained on the basis of five-co-ordination for the metal in these com-pounds.162 The first compound to contain Ti+-Sn bonds, tetrakistri-phenylstannyloxytitanium, (Ph3SnO),Ti, results from the reaction betweentetrabutyl titanate and triphenyltin hydr0~ide.l~~ Further phases M,X,M3X2, M4X3 have been identified among the sulphides, selenides, and telluridesof titanium, zirconium, and hafnium.la Studies have been made of theaminolysis of titanium and zirconium tetrachlorides : two chlorine atomsare eliminated with primary wines but only one with secondary amines.Many adducts have been reported but these probably contain solvolysedspecies.165 The dimerisation in (TiCl,,POC13), occurs through chlorinebridges ; phosphoryl chloride is co-ordinated to the titanium through theoxygen atom.lG6 Reduction of zirconium tetrachloride with lithium intetrahydrofuran in the presence of 2,2'-bipyridyl gives violet Zr (bipy),153 S.Hietanen and L. G. SillCn, Acta Chem. Scand., 1959, 13, 1828.154 J. L, Ryan, J . Phys. Chem., 1960, 84, 1375.155 W. Rudorff and H. Leutner, Annalen, 1960, 632, 1.156 R.E. Panzer and J. F. Suttle, J . Inorg. Nuclear Chem., 1960, 13, 244; 1960,157 B. J. McDonald and W. I. Stuart, Acta Cryst., 1960, 13, 447.158 J. Beukenkamp and K. D. Herrington, J . Amer. Chem. Soc., 1960, 82, 3025.159 A. Liberti and L. Ciavatta, J . Inorg. Nuclear Chem., 1958, 8, 365; V. Caglioti,L. Ciavatta, and A. Liberti, ibid., 1960, 15, 115.160 K. L. Berry, V. D. Aftandilian, W. W. Gilbert, E. P. H. Meibohm, and H. S.Young, J . Inorg. Nuclear Chem., 1960, 14, 231; cf. 0. Schmitz-DuMont and H. Reck-hard, Montash., 1959, 90, 134.161 S. Andersson and A. D. Wadsley, Nature, 1960, '187, 499.162 R. L. Martin and G. Winter, Nature, 1960, 188, 313.163 H. J. Cohen, J . Org. Chem., 1960, 25, 154.164 H. Hahn and P. Ness, 2. anorg. Chem., 1959, 802, 17, 37, 136; cf.Ann. Re$orts,165 J. E. Drake and G. W. A. Fowles, J., 1960, 1498; R. T. Cowdell and G. W. A.166 C.-I. BrandCn and I. Lindqvist, Acta Chem. Scand., 1960, 14, 726.15, 67.1959, 56, 148.Fowles, J., 1960, 2522; P. Dunn, Austral. J . Chem., 1960, 13, 225SHARP : THE TRANSITION ELEMENTS. 155containing Zr(0) .I67 The trilialides of zirconium can be prepared pure bythe action of a glow-discharge on the tetrahalides at a pressure of 3 4 mm.of hydrogen; the chloride and bromide are blue, and the iodide is greenish-black.168 Li,ZrF6 contains an octahedral ZrFG2- ion; this is in distinctionto the 8-co-ordination about the zirconium in K,ZrF6.169 A convenient newpreparative method for the zirconium alkoxides is the reaction betweenzirconium acetylacetonate and the free alcohol.170Vanadium, Niobium, and Tantalum.-Acid and neutral decavanadatescorresponding to the species present in rapidly hydrolysed vanadate solutionscan be isolated from solutions of pH 1.5 to pH 7.Spectrophotometricstudies on these solutions are considered to indicate the presence of onlyfour stable anions : mono-, di-, tetra-, and deca-~anadates.~~~ E.m.f.studies on equilibria in alkaline vanadate solutions have been interpreted interms of a series of tentative structures based on five-co-ordination aboutthe metal. The principal ions considered present are: vO,(OH),]2-,[(V02)2(OH)5]3-, and [(V0,),(OH)6]3-.172 Cryoscopic and spectrophotometricstudies on peroxyvanadates have established the existence of at least sevendifferent species, but the structures of these complexes are not yet clear.173The compounds KVC1, and K,VC14 are present in the system KCl-VCl,; inthe system CsCl-VC1, only CsVCl, is found, whilst NaCl-VC1, gives a simpleeutectic.174 Vanadium metal reacts with dinitrogen tetroxide in acetonitrileto give vanadium dioxynitrate, V02N0,.This is a brick-red solid, verysoluble in water; on heating it dissociates into V,O, and N205.175 Anexamination of the system Rb,O-Nb,05 has shown phases with the ratioof base to acid 1 : 4,4 : 11,4 : 1,2 : 15, 1 : 2, 2 : 3, 1 : 1, and 4 : 3.176 Physi-cal studies of aqueous solutions of niobates over the pH range 5 to 14 showthat there are three distinct types of condensed polyanions, all derivatives ofthe hypothetical hexaniobic acid.Na,NbO,, the most basic sodium niobate,can be extracted with ethanol from an NaOH-Nb,O, melt.177 The com-pounds NbS, (monoclinic) and NbS, (hexagonal, MoS, structure) are presentin the niobium-sulphur system; other phases present include two with com-positions near to NbS, and NbS.178 The most efficient reagent for reducingniobium pentachloride to the complex (Nb6Cl1,) C1,,7H20 is cadmiumamalgam ; 179 both niobium and tantalum pentachlorides form adducts with167 S. Herzog and H. Zuhlke, 2. Naturforsch., 1960, 15b, 466.lB8 I. E. Newnham and J. A. Watts, J . Amer. Chem. Soc., 1960, 82, 2113.169 R. Hoppe and W. Dahne, Naturwiss., 1960, 47, 397.170 €?. M. Brainina, R. K. Friedlina, and A. N. Nesmeyanov, Izucst.Akad. NazikS.S.S.R., Otdel. Khim. N a u k , 1960, 63 [54].171 0. Glemser and E. Preisler, 2. anorg. Chem., 1960, 303, 303; E. Preisler and0. Glemser, ibid., p. 316; cf. F. Chauveau, Bull. SOC. chim. France, 1960, 810; Ann.Reports, 1959, 56, 149.172 N. Ingri and F. Brito, Acta Chem. Scand., 1959, 13, 1971; F. Brito and N. Ingri,Anales real SOC. espaii. Fis. Quinz., 1960, 56, 165.173 F. Chauveau, Bull. SOC. chim. France, 1960, 819.174 H.-J. Seifert and P. Ehrlich, 2. anorg. Chew., 1959, 302, 284.175 J. A. Pantonin, A. K. Fischer, and E. A. Heintz, J . Inorg. Nuclear Chem., 1960,176 A. Reisman and F. Holtzberg, J . Phys. Chem., 1960, 64, 748.177 G. Jander and D. Ertel, J . Inorg. Nuclear Chem., 1960, 14, 71, 77, 85.178 F. Jellinek, G.Brauer, and H. Miiller, Nature, 1960, 185, 376.179 H. S. Harned, C . Pauling, and R. B. Corey, J . Amer. Chem. SOL, 1960, 82, 4816.14, 145156 INORGANIC CHEMISTRY.phosphorus pentachloride and phosphoryl chloride.lsO The magneticproperties of K,[NbsO,(SO,),~,2lH,O are best interpreted on the basis oftwo types of niobium atom with the ratio NbIII : NbV as 1 : 2. This complexis used in the separation of niobium and tantalum since tantalum is notreduced in sulphuric acid solutions.181 The aminolysis of tantalum penta-chloride has been studied. Monomethylamine and monoethylamine giveproducts TaC13(NHR),,2NH,R ; n-propyl- and n-butyl-amines giveTaCl,(NHR),,NHR,; dialkylamines give TaCl3(NR2),,NHR2 (R = Me, Et,and Prn) ; trialkylamines give adducts, TaC15,2NR, (R = Me and Et).I82Chromium, Molybdenum, and Tungsten.-KCrF, and KCuF, have dis-torted octahedra about the transition-metal atoms with four long and twoshort bonds; this is the same type of octahedral distortion as is found inK2CuF4.ls3 A phase study of the system NaC1-CrC1, shows the existenceof the compound Na3CrC15.184 Chromium tetrabromide appears as one ofthe volatile products when chromium tribromide is heated in an atmosphereof bromine.l= Potassium perchromate, K,CrO,, has the chromium atomsurrounded by four equivalent O,,- ions,the chromium being in the penta-positivestate.The peroxide ions are side-on tothe metal so that the effective co-ordin-ation number is eight.ls6 The phosphiteion forms surprisingly stable chelates withH,O’ ‘0 0‘ ‘OH, the chromium(m) ion.The free acid,H,[Cr(HPO,),], can be isolated and thecomplex ion resolved into its opticallyactive isomers .I87 Theoretical argumentssupport the structure (22) for the basic acetates of chromium, iron, andaluminium which contain [M,Ac,(OH),]+ ions. The metal atoms are con-sidered to be six-co-ordinate, two other acetate groups completing the octa-hedral co-ordination out of the OM, plane.ls8K-Molybdenum oxide has been confirmed as Mo17047. The structure,which is similar to that of W,804g, is built up from MOO, octahedra andMOO, pentagonal bipyramids with metal-metal bonding between pairs ofp0lyhedra.18~ An orthorhombic cobalt molybdate, CO,MO,O,~, can be grownfrom a melt of sodium molybdate, cobalt chloride, and sodium chloride.From the positions of the heavy atoms it appears most likely that the molyb-OH2 IM e .c / o ~ j \ O \ c / M e I? / O \ ! MI(2 2,‘&IMe180 R. Gut and G. Schwarzenbach, HeZv. Chim. Ada, 1959, 42, 2156; I. A. Sheka,B. A. Voitovich, and L. A. Nisel’son, Zhur. Izeorg. Khim., 1959, 4, 1803 [813].181 E. I. Krylov and N. N. Kalugina, Zhur. neorg. Khim., 1959, 4, 2476 [1138].18a P. J. H. Carnell and G. W. A. Fowles, J., 1959, 4113.18s A. J . Edwards and R. D. Peacock, J., 1959, 4126; cf. V. Scatturin, L. Corliss,184 J. C. Shiloff, J . Phys. Chem., 1960, 64, 1566.185 R. J . Sime and N. W. Gregory, J. Amer. Chem. SOC., 1960, 82, 93.186 R. Stomberg and C. Brosset, Acta Chem. Scand., 1960, 14, 441.187 J.Podlaha and M. Ebert, Nature, 1960, 188, 657; M. Ebert and J . Podlaha,188 L. E. Orgel, Nature, 1960, 18’9, 504; cf. K. Starke, J. Inorg. Nuclear Chem.,189 L. Kihlborg, Acta Chem. Scand., 1959, 18, 964; 1960, 14, 1612; cf. A. MagnBli,N. Elliott, and J. Hastings, Acta Cryst., 1961, 14, 19.Coll. Czech. Chem. Comm., 1960, 25, 2435.1960, 13, 254.Arkiv Kem., 1950, 1, 223SHARP: THE TRANSITION ELEMENTS. 157denum is present as tetrahedra.lgO Molybdenum trifluoride hasbeen re-examined and a yellowish compound with the VF, structure hasbeen isolated by the reduction of molybdenum pentafluoride with molyb-denum metal. It seems possible that previous attempts to prepare thiscompound resulted in the formation of an oxyfi~oride.~~~ Sodium iodidehas previously been shown to reduce molybdenum hexafluoride to NaMoVF,and it has now been shown that excess of sodium iodide gives dark-brownNa2MoIVF,.The hexafluoromolybdates(1v) are much more stable withrespect to hydrolysis than the hexafluoromolybdates(v) .lg2 The formationof molybdenum tetrachloride has been studied in some detail. It can beprepared by the action of chlorine on a suspension of molybdenum dioxidein hexachlorobutadiene or by heating an equimolecular mixture of the tri-and penta-chlorides in a sealed tube, Molybdenum trichloride dispropor-tionates to the di- and tetra-chlorides when heated but, under normalconditions, the tetrachloride undergoes further disproportionation and itcannot be isolated from this reaction.lg3 Molybdenum tri-iodide can beprepared by the action of excess of iodine on the metal in a sealed tube at300" or by the reaction between molybdenum pentachloride and hydrogeniodide in an inert solvent.When heated to 100" in an inert atmosphere itgives the di-iodide ; the tri-iodide appears to have a polymeric structure.194Molybdenum carbonyl reacts with carboxylic acids to give polymericmolybdenum@) carboxylates ; lg5 chloro-carboxylates, MoCl,(OOC*R),, areformed by the reaction between molybdenum pentachloride and carboxylicacids in carbon tetra~N0ride.l~~ MoS, is the only compound formed bydirect reaction of the elements; Mo~S, and MoS, result from the systemH,-H,S-MO.~~~J~~ The reaction between diphosphines and molybdenumcarbonyl gives phosphinemolybdenum carbonyls but the phosphines reactwith dibenzenemolybdenum to give the thermally stable complexesMo(diphosphine),(O) .lg8Potassiumcyanide reacts with tungstic acid to give K,[W(OH),(CN),],4H20, a saltcontaining an anion not previously reported for tungsten although cyanidesof this type are well known for molybdenum.This salt reacts with aceticacid to give I<,[W(OH),(H,O) (CN),],2H20 and with carbon dioxide to giveK2W( OH) ,( H20) ,(CN) ,] ,H20.199 Alkoxides, WO (OR),, and halogeno-alkoxides, WBr3(0R), and WBr,(OR),, result from the action of oxygen-containing compounds on tungsten oxytetrachloride or pentabromide inThere is little to report on the chemistry of tungsten.lgo G. W. Smith, Nature, 1960, 188, 306.lgl D.E. Lavalle, R. M. Steele, M. K. Wilkinson, and H. L. Yakel, jun., J . Amer.193 D. E. Crouch and A. Brenner, J . Res. "at. Bur. Stand., 1959, 63, A , 185; T. E.Austin and S. Y . Tyree, jun., J . Inorg. Nuclear Chem., 1960, 14, 141.194 J. Lewis, D. J. Machin, R. S. Nyholm, P. Pauling, and P. W. Smith, Cham. andInd., 1960, 259; F. Klanberg and H. W. Kohlschutter, 2. Nadurforsch., 1960, 15b,616.lg5 E. Bannister and G. Wilkinson, Chem. and Ind., 1960, 319.197 J. R. Stubbles and F. D. Richardson, Tmns. Faraday SOC., 1960, 56, 1460.lS8 J. Chatt and H. R. Watson, Proc. Chem. SOC., 1960, 243.lgg K. N. Mikhalevich and V. N. Litvinchuk, Zhur. neorg, Khim., 1959, 4, 1775[SOO]; V. N. Litvinchuk and K. N. Mikhalevich, Ukrain. khim. Zhur., 1959, 25, 563.Chem.SOC., 1960, 82, 2433.A. J. Edwards and R. D. Peacock, Chem. and Ind., 1960, 1441.M. L. Larson, J . Amer. Chem. SOL, 1960, 82, 1223158 INORGANIC CHEMISTRY.benzene. With some organic derivatives only partial solvolysis occurs andthere is often solvate formation.2mManganese, Technetium, and Rhenium.-Oxidation of hexakisisocyanide-manganese ( I) complexes gives salts of the [Mn (CNR),] 2-t- cations ; these arespin-paired manganese( 11) complexes.m1 The spin-free trisbipyridyl-manganese(@ cation is oxidised by persulphate to a greenish-black complexcation which has been formulated [bipy2MnIn< O,> MnKVbipyJ3+ withpossible metal-metal interaction. This cation is also prepared by the actionof persulphate on manganese(11) salts in the presence of 2,2'-bipyridy1.2*2Although periodates normally oxidise manganese@) to the perman-ganate ion, fairly stable complexes, Na,H4MnIV(I0,),, 17H20 andK,H4MnIV(10,),,8H20 can be prepared by the action of hypochlorite andperiodate on manganous salts.These tetrapositive complexes decompose togive permanganate and iodate.203 The +6 and +5 oxidation states oftechnetium are now well established. Chlorine oxidises the complex[Tc111D2Cl&l (D = o-phenylenebisdimethylarsine) to give eight-co-ordinatetechnetium in the brown [TcVD,C14]+ cation, which is similar to therhenium (v) derivative. Bivalent complexes, TcD,X,, have now been pre-pared for all the halogens.204 The +5 state was established polarographic-ally during the reduction of pertechnetate in @lM-pOtaSSiUm hydroxide ;reduction in 4~-hydrochloric acid gives an intermediate +6 state beforereduction to the +4 state.205 There has been an extensive re-investigationof rhenium fluoride chemistry.The action of a slight pressure of fluorine onrhenium metal at 400" gives ReF,, a pale-yellow solid which is now thehighest known binary metal fluoride,206 Metal carbonyls reduce rheniumhexafluoride to ReF5 (green-yellow), ReF, (pale blue), ReOF, (blue), andReOF, (black),207 More details have now been given of the complexesformed by rhenium trichloride and tetra-iodide with ligands containingnitrogen, phosphorus, oxygen, and sulphur. Many of the complexes arepolymeric with halogen bridges, but some five-co-ordinate rhenium (111)complexes [e.g., (Ph,P),ReCl,] were isolated. Re,O, or ReO, reacts directlywith acetylacetone to give rhenium(zr1) acetylacetonate.101*208 Salts con-taining the hexakis(toly1 isocyanide)rhenium(I) cation have been prepared ;this cation is very similar to the corresponding manganese derivati~e.~O~The action of potassium cyanide on rhenium-(III) or -(Iv) complexes giveseventually brown K,ReV(CN),.Atmospheric oxidation of a dilute acidsolution of this salt gives the purple [ReVI(CN)J2- anion; reduction ofK,Re(CN), with borohydride gives green &Re1**(CN),, which is also ob-200 H, Funk, W. Weiss, and G. Mohaupt, 2. anorg. Claem., 1960,304, 238; H. Funkand H. Schauer, ibid., 1960, 306, 203.201 L. Naldini, Gazzetta, 1960, 90, 871.202 R. S. Nyholm and A.Turco, Chem. and Ind., 1960, 74.203 M. W. Lister and Y. Yoshino, Canad. J . Chem., 1960, 38, 1291.204 J. E. Fergusson and R. S. Nyholm, Chem. and I n d . , 1960, 347.205 R. Colton, J. Dalziel, W. P. Griffith, and G. Wilkinson, J., 1960, 71.206 J. G. Malm, H. Selig, and S. Fried, J . Anaer. Chem. Sac., 1960, 82, 1510.207 G. B. Hargreaves and R. D. Peacock, J., 1960, 1099.208 R. Colton, R. Levitus, and G. Wilkinson, J., 1960, 4121; M. Tsin-Shen and V. G.209 L. Malatesta, M. Freni, V. Valenti, and E. Bossi, Angew. Ckeiit., 1960, 72,Tronev, Zhur. neorg. Khim., 1960, 5, 861 [415].323SHARP THE TRANSITION ELEMENTS. 159tained as an intermediate from the action of cyanide on rhenium(II1) salts.Hydroxyl ions react with the Re(CN)z- ion to give nine-co-ordinate[ Rem (CN) (OH)] 2- species.70Iron, Ruthenium, and Osmium.-A neutron-diffraction study of non-stoicheiometric FeO has shown that there are both cation vacancies in octa-hedral sites and interstitial cations in tetrahedral sites ; pure stoicheio-metric ferrites, MFe,O, (M = Mg2+, Mn2+, Co2+, and Fe2+) can be preparedby thermal decomposition of the crystalline acetates M,F~,Ac,,O,OH,~~~~.~~~Mixed ligand complexes between ferric or ferrous ions and 2,Z'-bipyridyl oro-phenanthroline and cyanide ions have been re-described.The ferrouscomplexes are protonated, possibly on the metal atom, when dissolved inacids and salts can be isolated.a2 Triphenyl-phosphine and -arsine com-plexes have now been described for each element of this triad.Iron(@halides give the complexes FeL2X2 and FeL,X,, while ruthenium trichlorideand ammonium hexachloro-osmate(1v) are reduced to univalent complexesM1L3C1.,13 Spectrophotometric studies have established that the ruthen-ate(vr) ion is present in aqueous solution as RuO,~- but that the osmate(vr)ion exists, both in solution and in the solid potassium salt, as the octahedralion, [OSO~(OH)~]~-. The decomposition of the per-ruthenate(vI1) ion,RuO,-, to ruthenate(v1) in alkaline solution appears to be by attack of per-ruthenate ion on an octahedral [Ru~I~O,(OH),]~- anion formed by additionof hydroxyl ions to per-ruthenate.z16 Bromine trifluoride acts on a mixtureof sodium or lithium chloride and ruthenium trichloride to give hexafluoro-ruthenates(v) ; contrary to previous reports these particular salts are quitestable.215 A thorough investigation of the phosphides of the platinummetals has shown that the phases present are M2P, MP, MP,, and MP,.2f6A new species, RuCIZfaq, has been identified in solutions of tervalent ruthen-ium in hydrochloric acid.There are two isomers of this formula and it ispostulated that these are the cis- and trans-forrn~.~~~ The species present insolutions of ruthenium(1v) in hydrochloric acid are [Ru(OH)J2+, Ru(OH),Cl,,[Ru(OH),C1J2-, and RuC1,2-.218 The volatility of the platinum metals inoxygen at high temperatures has been investigated. Osmium and rutheniumgive gaseous trioxides in the range 800" to 1500" and osmium gives OsO,above this temperature; rhodium and platinum are volatilised as the di-oxides and iridium as the t r i ~ x i d e .~ ~ ~ Tungsten carbonyl reduces osmiumhexafluoride to blue OsF, and yellow OsF,. Osmium pentafluoride can also210 W. L. Roth, Acta Cryst., 1960, 13, 140.211 D. G. Wickham, E. R. Whipple, and E. G. Larson, J . Inorg. Nuclear Chcnz.,212 A. A. Schilt, J . Amer. Chern. SOL, 1960, 82, 3000, 5779.213 L. Naldini, Gazzetta, 1960, 90, 391; L. Vaska, 2. Naturforsch., 1960, 15b, 56;214 A. Carrington and M. C. R. Symons, J., 1960, 284; K. A. K. Lott and >I. C. R.215 J. L. Boston and D. W. A. Sharp, J., 1960, 907.216 S. Rundqvist, Nature, 1960, 185, 31.217 R. E. Connick and D. A. Fine, J . Amer. Chem. SOL, 1960, 82, 4187.218 V. I. Paramonova and E. F. Latyshev, Radiokhimiya, 1959, 1, 458.219 C.B. Alcock and G. W. Hooper, Proc. Roy. SOC., 1960, 254, 551; H. Schafer andA. Tebben, 2. anorg. Chem., 1960, 304, 317; H. Schafer and H.-J. Heitland, ibid.,p. 249; R. T. Grimley, R. P. Burns, and M. G. Inghram, J. Chewz. Phys., 1960, 33,308; H. SchUer, W. Gerhardt, and A. Tebben, Angew. Chem., 1961, 73, 27.1960, 14, 217.L. Vaska and E. M. Sloane, J . Amer. Chem. SOC., 1960,82, 1263.Symons, J., 1960, 973160 INORGANIC CHEMISTRY.be prepared by reduction of the hexafluoride with iodine in iodine penta-fluoride or by photolysis of the hexafluoride.220 Ruthenium and osmiumtetroxides form 1 : 1 adducts with ammonia. The ruthenium compoundexplodes at -20" but the osmium derivative can be sublimed; on heating,the latter compound gives free osmiamic acid, HNOSO,.~~~ t-Butylamineand 1,1,3,3-tetramethylbutylamine react with osmium tetroxide to give thecorresponding N-alkylosmiamates without formation of the intermediateadduct s.222Cobalt, Rhodium, and Iridium.-Extensive measurements have beenmade on the magnetic properties of cobaltous and cobaltic ions in variousenvironments.223 Full details have been published for the preparation ofthe carbonato-complex N~,[CO~~*(CO,)~] ,3H,O which appears to be a veryuseful intermediate for the preparation of cobaltic complexes.2a Both cis-and trans-forms of the dibromide [CoInLBr2] + (L = triethylenetetramine)can be isolated, whereas the dichloro- and dinitro-complexes can only beobtained in the cis-forms.It has been proposed that the large size of thebromide ions makes the cis-configuration less stable.225 When excess ofcyanide ion interacts with hexamminecobalt (111) or pentamminecobalt (111)derivatives in dilute solution only five cyanide ions are taken up per metalatom and the substitution of the final co-ordination position is very slow;in concentrated solutions all six co-ordination positions are substitutedslowly.Kinetic measurements show that the rate of entry of cyanide ionsinto cobalt(II1) complexes is greater than the rate of entry of hydroxyl ionsso that cyanide complexes are kinetically stable with respect to hydrolysis.226trans-K[Co111dmg2(CN)J, 1.5H20 (dmg = dimethylglyoximato) can be re-duced to blue K,I[COI~~~,(CN)~]. This is an air-sensitive compound whichis easily re-oxidised to the cobalt (11) complex.227 Rhodium and platinumtetrafluorides react with selenium tetrafluoride to give adducts, (RhF4),SeF4and PtF2,2SeF,, of unknown structures.228 Details have been given for thesynthesis of the cis- and trans-[Rh en,Cl,]+ ions, the first tetrammine com-plexes of rhodium.229Nickel, Palladium, and Platinum.-Nickel chloride reacts with sodiummethoxide to give nickel methoxide, which takes up carbon disulphide toform nickel xant hat e .DO The magnetic proper ties of N-alkylsalicylaldimine-nickel(I1) complexes have been explained in terms of mixed singlet and tripletstates, but strong intermolecular association could also give rise to the220 G.B. Hargraves and R. D. Peacock, J., 1960, 2618.221 M.L. Hair and P. L. Robinson, J., 1960, 2775.222 N. A. Milas and M. I. Iliopulos, J. Amer. Chem. SOC., 1959, 81, 6089.223 F. A. Cotton and R. H. Holm, J . Amer. Chem. SOC., 1960, 82, 2979, 2983; R. H.Holm and F. A. Cotton, J. Chem. Phys., 1960,32, 1168; F. A. Cotton and M. D. Meyers,J. Amer. Chem. SOC., 1960, 82, 5023; M. D. Meyers and F. A. Cotton, ibid., 1960, 82,5027.224 H. F. Bauer and W. C. Drinkard, J. Amer. Chem. SOC., 1960, 82, 5031.225 J . Selbin and J. C. Bailar, jun., J. Amev. Chem. Soc., 1960, 82, 1624.226 H. S. Nagarajaiah, A. G. Sharpe, and D. B. Wakefield, Proc. Chem. Soc., 1959,385; B. P. Block, J. Inorg. Nuclear Chem., 1960, 14, 294; D. A. L. Hope and J . E.Prue, J., 1960, 2782.227 N. Maki, Nature, 1960, 188, 227.228 M.L. Hair and P. L. Robinson, J., 1960, 3419.229 S. Anderson and F. Basolo, J. Amer. Chem. Sot., 1960, 82, 4423.230 M. Nehm6 and S. J. Teichner, BUZZ. SOC. chim. Fvulzce, 1960, 659SHARPE : THE TRANSITION ELEMENTS. 161observed ~alues.23~ It has been suggested that distorted tetrahedralanions, [NiLX,]-, are present in the complexes that result from, e.g., theinteraction of tetraethylammonium bromide , triphenylphosphine, and nickelbromide in butan01.~~~ There have been claims for both the [Ni(CN),J3- and[Ni(CN)J4- ions in the system [Ni(CN)J+-CN-. Ultraviolet spectroscopicstudies suggest the presence of the pentacyano-derivative but determinationsof relaxation times by nuclear magnetic resonance spectroscopy are equallyconclusive in being in favour of the hexacyano-ion.233 Bis(ethylmethy1-glyoximato)nickel(rr) is a tram-planar complex but there is no metal-metalbonding as in the dimethyl derivative ; 234 bis(dimethylg1yoximato)-palladium(11) contains weak metal-metal bonds.% Some very interestingobservations on metal-metal bonding have been made on the series of iso-structural complexes [MLdwXd (M = Cu, Pd, or Pt; N = Pd or Pt;L = NH, or MeNH,; X = C1, Br, or SCN).Except when M = N = Ptthe colours of these complexes are those of the constituent ions but whenM = N = Pt-and presumably the d orbitals are of sufficient size for over-lap-the complexes have the green colour which has been associated withmetal-metal bonding. When L is ethylamine the platinum complexes arepink, and the large ligands seem to have forced the ions apart.It is signi-ficant that the bonding is a result of the structure and not vice Theinfrared spectra of sulphito-complexes of palladium suggest that the bond-ing to the metal is through the sulphur atom.=' New platinum fluorides,PtF, and PtOF,, both dark-red solids, are formed in addition to the pre-viously described hexafluoride when fluorine reacts with platinum at 350°.=The fact that ligand exchange in the trans-[Pten,ClJ2+ ion is catalysed byplatinous complexes has been made use of in the synthesis of a series of[Pten,Xd2+ salts. A catalytic amount of Pten,Cl, is added to the [Pten,C1,I2+ion together with the anion required for s u b s t i t ~ t i o n . ~ ~ The platinumammines [Pt(NH,),Cl,]Cl and cis- and t~ans-[Ptpy,(NH,),Cl&l, react withchlorine to give the N-dichloramide derivatives Pt (NH,),(NCl,)Cl,,Pt py, (NCl,) ,C1, , and [ Ptpy, (NH,) (NC1,) C1.J C1 , respectively.m Dimet hyl-o- (methy1thio)phenylarsine complexes of platinum are of the types PtRX,and PtR,X,.The latter complexes are 1 : 1 electrolytes in non-aqueoussolvents and seem to contain five-co-ordinate metal atoms as do the palladiumderivatives and as are also postulated for diarsine complexes of palladiumand platinum.Mla31 L. Sacconi, R. Cini, M. Ciampolini, and F. Maggio, J . Amer. Chem. SOL, 1960,82, 3487; R. H. Holm and T. M. McKinney, ibid., p. 5506.232 F. A. Cotton and D. M. L. Goodgame, J . Amer. Chem. SOC., 1960, 82, 2967.233 R. L. McCullough, L.H. Jones, and R. A. Penneman, J . Inorg. Nuclear Chem.,1960, 13, 286; M. S. Blackie and V. Gold, J., 1959, 4033; L. KSovS and V. CuprovS,Chem. Listy, 1958, 52, 1422.284 E. Frasson and C . Panattoni, Ada Cryst., 1960, 13, 893.236 C. Panattoni, E. Frasson, and R. Zannetti, Gazzettu, 1969, 89, 2132.236 J. R. Miller, Proc. Chew. Soc., 1960, 318; S. Yamada and R. Tsuchida, Bull.Chem. SOC. Japan, 1958, 31, 813; cf. M. Bukovska and M. A. Porai-Koshits, KrystaZZo-grufiya, 1960, 5, 137 [127].257 G. A. Earwicker, J., 1960, 2620.2s3 N. Bartlett and D. H. Lohmann, Proc. Chem. Soc., 1960, 14240 Y. N. Kukushkin, Zhur. neorg. Khim., 1957, 2, 2371; 1959.4, 2460 [1131].241 B. Chiswell and S. E. Livingstone, J., 1960, 1071; cf. S. E. Livingstone, J.,R.C. Johnson and F. Basolo, J . Inorg. NucZear Chern., 1960, 13, 36.1958,4227; C. M. Harris, R. S. Nyholm, and D. J. Phillips, J., 1960,4379.REP.-VOL. LVII r162 INORGANIC CHEMISTRY.Copper, Silver, and Gold.--Copper(n) salts are hydrolysed to hydroxy-species of the type [Cu,40H)%,_2j2+, in alkaline solution; the monomeric ion,[CuOH]+, is not present in appreciable amounts.242 LiCuC1,,2H20 containsplanar [CU,C~,]~- ions with symmetrical Cu-C1-Cu bonds ; these units arelinked into chains by longer Cu-Cl bonds and the magnetic interactions inthe crystals run along these chains.w A series of dark-coloured chloro-cuprates containing both copper@) and copper(I1) can be crystallised fromsolution ; the colour and chemical composition depend upon the constitution0 of the mother liquor.244 The gaseous copperI nitrate molecule has the structure (23) ; this modelis consistent with the chemical properties which N/ \indicate that one of the nitrate groups is more labile0 0 than the other.245 The infrared spectrum of thecomplex Cu(NO,),,N,O, indicates that the structurein the solid state may be [NO]+[Cu(NO,)J-; however, the adduct is dissoci-ated into its components in solution.246 A partial structure determinationon the tripositive copper complex Na,KH,[Cu(IO,),] indicates that the co-ordination about the copper is square planar.247 (Methyl isocyanide)-copper(1) iodide is formed by the interaction of cuprous iodide and methylisocyanide or of cuprous cyanide and methyl iodide.The crystal lattice haschains of copper and iodine atoms; each copper atom is bound to twoiodine atoms and two isocyanide groups and there are also short Cu-Cu dis-tances which may indicate metal-metal bondingN8 In the complex formedby the action of diazomethane on cuprous chloride there are also infinitecopper-halogen chains but these are joined in pairs by further Cu-C1 bonds.Cross-linkage of chains via the trans-diazomethane molecule occurs throughCu-N bonds and the co-ordination about the copper is approximately tetra-hedra1.249 Another interesting stereochemical arrangement about copperoccurs in the tetrakis-(4-methylimidazole)copper(11) ion.The configurationabout the copper is planar and the steric hindrance of this arrangement isrelieved by rotation of the imidazole rings.250 Five-co-ordinate copper occursin NN’-disalicylidenepropane-l,2-di-iminecopper (11) hydrate and in NN‘-di-salicylidene-ethylenediaminecopper(I1). In the first complex the co-ordina-tion is from two nitrogen and two oxygen atoms in a plane with further co-ordination from the water molecule perpendicular to the plane; in the lattercomplex the true molecule is a dimer with normal co-ordination in a planeand further co-ordination to an oxygen atom in the other half of the mole-cule.251 1,3-Diphenyltriazen (24) forms a complex of the type Cu2L, with242 D. D. Perrin, J., 1960, 3189.243 P. H. Vossos, L. D. Jennings, and R. E. Rundle, J. Chem. Phys., 1960, 32, 1590.244 M. Moki, Bull. Chem. SOC. Japan, 1960, 33, 985.245 S. H. Bauer and C. C. Addison, Proc. Chem. SOL, 1960, 251; C. C. Addison,B. J . Hathaway, N. Logan, and A. Walker, J., 1960, 4308.24~5 C. C. Addison and B. J. Hathaway, J., 1960, 1468.247 I. Hadinec, L. JenSovskq, A. Linhk, and V. SynEcek, Natzcrwiss., 1960, 47, 377.248 H. Irving and M. Jonasen, J., 1960, 2095; P. J . Fisher, N. E. Taylor, and M. M.2QB I. D. Brown, and J. D. Dunitz, A d a Cryst., 1960, 13, 28.260 H. Montgomery and E. C. Lingafelter, J . Phys. Chem., 1960, 64, 831.251 F. J . Llewellyn and T. N. Waters, J., 1960, 2639; D. Hall and T. N. Waters,I * *- Cu-,N,(23).Harding, J.. 1960, 2303.J., 1960, 2644SHARP THE TRANSITION ELEMENTS. 163cupric ions. The complex salt is dimeric and this ligand does not appear toact as a chelating agent. The magnetic moment indicates that there ismetal-metal bonding, and a similar interaction is postulated for the dimericnickel(I1) and palladium(@ salts.252 Potassium in liquid ammonia reducescopper (11) phthalocyanine to dipotassiumcopper (0)phthalo~yanine.~~NPh-Nd 'N-Ph (24)HA neutron-diffraction study of Ago shows that there are two types ofsilver atom in the lattice. One has linear co-ordination to two oxygenatoms and is apparently silver(1) and the other is square-planar with respectto co-ordination by oxygen and is apparently silver(II1). This result is inaccordance with the diamagnetism of the oxide.2M The [Ag(OH)J- ionis the main species present in alkaline solutions of silver(1) An-hydrous silver fluoroborate may be prepared by passing boron trifluoridethrough a suspension of silver(1) fluoride in nitromethane or benzene.Benzene gives an adduct which can be decomposed by heating to 50" inD ~ C W O . ~ ~ ~ Complex cations of the type [Ag,X]m+ are formed when silversalts of strong acids react with silver salts of acids of the non-metals ofgroups VI and VII. Some solid salts have been isolated and typical cationsdescribed are [Ag,S] +, [Ag8Te]6+, [Ag6.,5Te]475+, [Ag,Br] +, and [Ag21 J +.257The lattice of AgSCNPrn,P has quasi-planar eight-membered rings formedby silver atoms linked by two thiocyanate groups, the rings being furtherlinked into chains by Ag-S bonds. The phosphine is joined to the silver,and the co-ordination about the metal is that of a very distorted tetra-hedron.2s Auric ions react with cyanide in alkaline solution to give complexanions in which the ratio Au : CN is 1 : 5 and 1 : 6; these are in addition tothe [Au(CN)d- ion present in neutral s0lution.~5~Zinc, Cadmium, and Mercury.-Zinc oxide and zinc halides are appreciablyvolatile in an atmosphere of zinc. The sublimate from the passage of zincover zinc chloride has the approximate composition ZnCl but the otherhalides give sublimates of composition ZnX,. It is possible that theseexperiments illustrate the formation of univalent zinc derivatives or itmay be that zinc metal catalyses the decomposition of zinc compounds.260Two zinc peroxide hydrates formulated HOOZnOH and HOOZn*O*ZnOOHhave been shown to be formed from aqueous solutions of zinc salts and252 C. M. Harris, B. F. Hoskins, and R. L. Martin, J., 1959, 3728.253 G. W. Watt and J. W. Dawes, J . Inorg. Nuclear Chem., 1960, 14, 32.254 V. Scatturin, P. Bellon, and A. J. Salkind, Ricerca sci., 1960, 30, 1034; cf. J. A.255 P. J . Antikainen and D. Dyrssen, Acta Chem. Scand., 1960, 14, 86; P. J. Anti-258 G. A. Olah and H. W. Quinn, J . Inorg. Nuclear Chem., 1960,14, 295; I<. Heyns257 K. H. Lieser, 2. anorg. Chenz., 1960, 304, 296; 305, 133, 255; B. Reuter and258 A. Turco, C. Panattoni, and E. Frasson, Nature, 1960, 187, 772.260 W. J. Moore and E. L. Williams, J . Phys. Chem., 1959, 63, 1516; E. A. Secco,Canad. J . Chew., 1960,38,596; D. H. Kerridge, Chem. and Ind., 1960, 1266.McMillan, J . Inorg. hTuclear Chem., 1960, 13, 28.kainen, S. Hietanen, and L. G. Sillen, ibid., p. 95.and H. Paulsen, Angew. Chem., 1960, 72, 349.K. Hardel, Angew. Chem., 1960, 72, 138.P. 0. Finsen and K. A. Murray, J.S. African Chew. Inst., 1960, 13, 48164 INORGANIC CHEMISTRY.hydrogen peroxide ; 261 the slow oxidation of diethylzinc and di-n-butylzincgives NN' -Disalicylidene-e t hylenediaminezinc (11)hydrate has a five-co-ordinate zinc atom, the co-ordination being from twonitrogen and two oxygen atoms in one plane with further co-ordinationfrom the water molecule perpendicular to this plane.263 Hydrated mercuriccyanide reacts with mercuric oxide to form Hg(0H)CN; the formation of thiscompound is probably the explanation for the solubility of mercuric oxidein mercuric cyanide solution.2Mdial k ylperox y zincs. 262D. W. A. S.D. W. A. SHARP.A. G. SHARPE.261 L. V. Ladeinova, Izvest. Akad. Nauk S.S.S.R., Otdel. khim. Nauk, 1959, 19526* M. H. Abraham, J., 1960, 4130.263 D. Hall and F. H. Moore, PYOC. Chem. SOC., 1960, 256.264 L. Newman and D. N. Hume, J . Amer. Chem. SOC., 1959, 81, 6901; cf. A. Weiss[181].and G. Hofmann, 2. Nuturjorsch., 1960, 15b, 679

ISSN:0365-6217    

DOI:10.1039/AR9605700115

出版商:RSC    

年代:1960

数据来源: RSC

摘要:

ORGANIC CHEMISTRY1. INTRODUCTIONIN the theoretical section of this Report nucleophilic aromatic substitutionis dealt with, as well as the more frequently covered free-radical and electro-philic substitution. It is claimed that Ph,O+ undergoes exclusive paya-substitution by electrophilic reagents. Theoretical matters relating toheteroaromatic systems are also included. In addition, carbonium ions,carbanions, reactions at carbonylic centres, and deuterium isotope effectsare reviewed.Among general synthetic methods hydroboronation receives furtherattention, and useful methods for halogeno-compounds are dealt with,especidy the use of the versatile fluorinating agent, sulphur tetrafluoride.The importance of solvent participation in preparative reactions is alsoemphasised and reviewed.Magnesium halides have been shown to catalysethe reactions of dialkylcadmium derivatives.Advances continue in the field of acetylenic, allenic, and ethylenic com-pounds, both natural and synthetic. Developments in the chemistry offatty acids, natural fats, and related substances are summarised. Ananalogue of the well-known thermal decomposition of ricinoleic acid hasbeen developed as a versatile chain-extension method.In the aromatic field, besides work on substitution and on macrocyclicaromatic compounds, intense research into the chemistry of the tetracyclinescontinues. Also an alkali-soluble hydrocarbon 1,9-o-phenylenefluorene hasbeen discovered. Much rather specialised work on metallocenes has ap-peared, and developments in tropolone chemistry continue to be reported.Of late, there has been a great increase in knowledge of the biosynthesis ofaromatic compounds.The first compound with interlocked rings (" catenanes ") has beenprepared. The total synthesis of (+)-podocarpic acid is reported, thestructure of limonin has been established, and there have been valuabledevelopments in knowledge of the gibberellins.The outstanding development in heterocyclic chemistry is the totalsynthesis of chlorophyll with the synthesis of chlorin e, trimethyl ester(p.280), reported almost simultaneously by Woodward and his colleaguesat Harvard, and by Strell, Kalojanoff, and Koller. In the alkaloid fieldthe constitution of calycanthine has been fully established and the argumentsin favour of the accepted structure of delphinine presented in detail. Thestructures of several Lycopodizcm alkaloids have been elucidated.The use of gas chromatography in the separation of sugar derivativesand of steroids is an important development.Periodate oxidation of sugarscontinues to receive important attention.The number of known biochemically important nucleotide anhydrideshas increased, and significant progress has been made with the isolation andfractionation of " native " nucleic acids. Fruitful physicochemical studiescontinue to play an important rble in nucleic acid chemistry166 ORGANIC CHEMISTRY.Interesting methods have been developed for the partial synthesis of18-oxygenated steroids, among which a photochemical reaction of nitrousesters is especially important.Valuable new total syntheses of adreno-sterone, cortisone, and cestrone, among others, have appeared.T. S. S.N. B. C .2. THEORETICAL ORGANIC CHEMISTRYCarbonium Ions.-Classical and non-classical iolzs. An improved methodfor obtaining crystalline triarylcarbonium salts, e.g., Ph3C+C104- andPh,C+BF,-, has been described.l" Carbonium ions have a capacity forhydride abstraction 2a and, when the anionic partner has a low nucleo-philicity, new carbonium salts can be prepared: RH + R'+C10,- +R+C104- + R'H. The triphenylmethyl cation reacts with cycloheptatrieneto form the cycloheptatrienyl cation,"b with (C,H,)Mo(CO), to yield(C,H,+)MO(CO),,~~ and with triphenylcyclopropene to yield the triphenyl-cyclopropeniurn ion.ld The triphenylmethyl cation also abstracts deuteridefrom deuteroformic acid: Ph,C+ + DCO,H -+ Ph,CD + CO, + H+.The electronic absorption spectra, and the chemical and the thermodynamicstabilities, of monoalkylaryl cations in sulphuric acid have been determinedas a function of cationic structure.26 The absorption band which developswhen isobutene or t-butyl alcohol, chloride, bromide, or acetate is dissolvedin concentrated sulphuric acid4C has been ascribed to the t-butyl cation.4uThe presence of cations in appreciable concentrations in solutions of tertiaryalcohols in concentrated sulphuric acid has been previously invoked.&Compelling evidence would be awaited with interest since t-butyl hexa-chloroantimonate and tetrafluoroborate appear not to absorb in this region; 5anor do the corresponding trialkylborine~.~~ The blue colour obtained from1,l-di-(@-methoxypheny1)ethylene in formic acid appears to be dueto [Ar,C=CHCH*CH=CArJ+HCO,-.Trichloromethylpentamethylbenzeneionises in 100% sulphuric acid to the ion (27) :Me Me 8 Me Me Me MeMe\ , CC13 + 2H2S04 -+ M e o C t C I 4- 2HCI t 2HSOT(27)1 (a) H. J- Dauben, jun., L. R. Honnen, and K. M. Harmon, J . Org. Chem., 1060,25, 1442; (b) H. J. Dauben, jun., F. A. Gadecki, K. M. Harmon, and D. L. Pearson,J . Amer. Chem. SOC., 1957, 79, 4557; (c) H. J. Dauben, jun., and K. M. Harmon, Abs.134th Meeting Amer. Chem. SOC., Chicago, Ill., Sept. 9th, 1958, p. 3 5 ~ ; (d) H. J. Dauben,jun.! and L. R. Honnen, J .Amer. Chem. SOC., 1958, 80, 5570; Abs. 15th SouthwestRegional Meeting Amer. Chem. SOC., Baton Rouge, La., Dec. 3rd, 1959, p. 89. * (a) N. C. Deno, H. J. Peterson, and G. S. Saines, Chkm. Rev., 1960, 60, 7; (b) N. C.Deno, P. T. Groves, J. J. Jaruzelski, and M. N. Lugasch, J . Amer. Chem. SOC., 1960,82, 4719.8 R. Stewart, Canad. J . Chem., 1957, 35, 766.4 (a) J, Rosenbaum and M. C . R. Symons, Mol. Phys., 1960, 3, 205; (b) V. F. Lav-rushin, N. N. Verkhoud, and P. K. Moneham, J . Gen. Chem. S.S.S.R., 1956, 26, 3005; cf.however (c) J. Gonzales Vidal, E. Kohn, and F. A. Matsen, J . Chem. Phys., 1956,25, 181.6 (a) Y. Pocker, unpublished observations; (b) A. G. Davies, D. G. Hare, and L. F.I,arkworthy, Chem. and Ind., 1959, 1519.R. C. Cookson, J.Rosenbaum, and M. C . R. Symons, Proc. Chem. SOC., 1960,353.7 11. Hart and R. W. Fish, J . Amer. Chem. SOL, 1960, 82, 5419POCKER THEORETICAL ORGANIC CHEMISTRY. 167At low concentrations the ionised portion of tri-(P-methoxypheny1)-methyl chloride in nitrobenzene is almost entirely in its dissociated form.8The long-lived 9-methoxyphenylcamphenyl cation is produced from bothendu- and exo-2-~-methoxyphenylcamphenilol in formic acid and it rapidlyapproaches equilibrium with 2-endo-~-methoxyphenyl-2-exo-methyl-3-methylenebornane (" fi-anisylapocamphene ") . The distribution of thecation between various products is de~cribed.~ Under kinetic controlthe distribution in a carbonium-ion intermediate involved in a Wagner-Meenvein rearrangement is such that reaction with nucleophiles predominatesat the cationic site which bears the greater number of alkyl substituents.l*The acid-catalysed rearrangement of diethyl ketone to methyl n-propylketone involves a carbonium-ion intermediate.llThe product of reaction of triphenylmethyl halides with alkali thio-cyanates appears to be the isothiocyanate.12" The isomerisation of di-phenylmethyl and allylic thiocyanates to isothiocyanates has been inter-preted in terms of ion-pair intermediates.12h$c Actually, both the allylicazide rearrangement 13a and the isomerisation of allylic thiocyanates 12bvshow very low solvent-sensitivity and similar A S values, and the mechanismcould be classified as nearer to a cyclic rearrangement.It is also conceivablethat these isomerisations partake partly of the character of an intramolecularaddition.l3"Pb In the absence of added base, thionyl chloride withoutsolvent or in dilute ethereal solution converts l-methylallyl alcohol intothe but-2-enyl chloride, and the but-2-enyl alcohol into the l-methylallylch10ride.l~" These results accord equally with a cyclicwith one involving a rigidly oriented ion pair.S,l mechanism orIn acetolysis artti-norbornen-7-yl toluene-9-sulphonate (28 ; X =$-C,H,Me*SO,) is more reactive than the norborn-7-yl derivative (30) by afactor of loll, while the syn-isomer (29) is more reactive by a factor ofonly lo*.The norbornadienyl chloride (31) in 80% aqueous acetone atE. Price and N. N. Lichtin, Tetrahedron Letters, 1960, No. 18, 10; see also Y .Pocker, Ann.Re$orts, 1959, 56, 168.P. D. Bartlett, C. E. Dills, and H. G. Richey, jun., J . Amer. Chenz. SOC., 1960, 82,5414.10 J. Berson, Tetrahedron Letters, 1960, No. 16, 17; P. Beltrame, C. A. Bunton, andD. Whittaker, Chem. and Ind., 1960, 567.l1 A. Fry, M. Eberhardt, and J. Ookuni, J . Org. Chem., 1960, 25, 1253.la A. Iliceto, A. Fava, and U. Mazzucato, (a) J . Org. Chem., 1960,25, 1445; (b) Tetra-hedron Letters, 1960, No. 11, 27; (c) F. A. s. Smith and D. W. Emerson, J . Amer. Chem.SOC., 1960, 82, 3076.(a) A. Gagneaux, S. Winstein, and W. G. Young, J . Amer. Chem. SOC., 1960, 82,5956; (b) E. A. Chandross and G. Smolinsky, Tetrahedron Letters, 1960, No. 13, 19;(c) W. G. Young, I;. F. Caserio, jun., and D. D. Brandon, jun., J .Amer. Chem. SOL,1960, 82, 6163168 ORGANIC CHEMISTRY.25.0" is ca. 760 times more reactive than anti-norbornen-7-yl chloride andon this basis it is ca. 1014 times more reactive than the norborn-7-yl analogue.It is suggested that the norbornadien-7-yl cation is highly stabilised by non-classical electron delocalisation.18"In 96% sulphuric acid, norbornadien-7-01 gives a yellow solution withan ultraviolet absorption band (Im= 3500 A; E 5000).14" Analogy withother work led Winstein et al. 14a to suggest that this might be thespectrum of the non-classical cation norbornadienyl. However, the ultra-violet spectrum of norbornadien-7-yl tetrafluoroborate at -80" in liquidsulphur dioxide showed no absorption above 330 mp.lad The nuclearmagnetic resonance spectrum of this solution at -10" eliminated any sym-metrical structure but was consistent with one of the catonic structuresoriginally suggest ed.l*There is strong indication of hydrogen participation in the ionisation ofdecahydrodimethanonaphthalene 9-bromobenzenesulphonate (32) .lSa Thesolvolytic reactions of pentamethylcyclopentadienylmethyl toluene-p-sulphonate and 9-bromobenzenesulphonate indicate l6b$ that ionisationof these compounds is anchimerically assisted by a factor of at least lolo.It is suggested that the assisted ionisation leads to non-classical homoallylicions, but it is not clear how many discrete electron-delocalised structureshave to be invoked.16b,cIn the addition of hydrogen bromide or acetic acid to elzdo-dihydro-dicyclopentadiene, the endo to exo isomerisation is incomplete and even inthe addition of formic acid, where thermodynamic control is operative, theexo to endo product ratio is only 99: 1.lhlb Similarly, the sulphuric acid-catalysed rearrangement of endo-tetrahydrodicyclopentadiene produces atequilibrium a mixture containing 99% of exo- and 1% of endo-material.16bThe question whether protonated cyclopropanes can be transient storageconfigurations for the neopentyl cation has aroused recent interest, and ithas been shown by isotopic labelling 1 7 9 1 8 that this is not the case.Addition, elimination, and exchange.Evidence from the acidity- andtemperature-dependence of rates of l80 exchange and of dehydration oftertiary alcohols in aqueous acids indicates that these two reactions proceedby common initial steps but involve different rate-determining steps.1914 (a) S.Winstein and C. Ordronneau, J . Amer. Chem. Soc., 1960, 82, 2084; (b) J. A.Grace and M. C . R. Symons, J., 1969, 958; (c) G. Leal and R. Pettit, J . Amev. Chem.SOC., 1959, 81, 3160; (d) P. R. Story and M. Saunders, ibid., 1960, 82, 6199.16 (a) S. Winstein and R. L. Hansen, J . Amev. Chem. SOC., 1960, 82, 6208; (b) L. deVries, ibid., p. 6242; (c) S. Winstein and M. Battiste, ibid., p. 5244.l6 (a) S. J. Cristol, W. K. Seifert, and S . B. Soloway, J . Amer. Chem. SOC., 1960, 82,2352; (b) P. von R. Schleyer and M. M. Donaldson, ibid., p. 4645.17 P. S. Skell, I. Starer, and A. P. Krapcho, J . Amer. Chem. Soc., 1960, 82, 5257.l8 G.J. Karabatos and J. D. Graham, J . Amer. Chem. SOC., 1960, 82, 5250.1s R. H. Boyd, R. W. Taft, jun., A. P. Wolf, and D. R. Christman, J . Amev. Chem.SOC., 1960, 82, 4729, and earlier references to Taft's work given in this paperPOCKER : THEORETICAL ORGANIC CHEMISTRY. 169The results are consistent with mechanistic scheme (a) involving carboniumions which are still shielded by the leaving group-" encumbered ions "-and the scheme (b) involving solvated but otherwise free carbonium ions:+Scheme (a): I , ROH + H,Of -' ROH, + H,O2, ROH, R+. . .OH,3, Rf.. .OH, [ > C = T C+HH+Scheme (b): I , ROH + H,O+ e' ROH, + H,O2, R ~ H , 3 - ~ . R+ + H,O3, R+ + H,O -. Olefin + H30+In scheme (a) steps 1, 2, and 4 are fast, and step 3 is rate-determining indehydration, while in l80 exchange step 1 is fast and step 2 is rate-deter-mining. In scheme (b) steps 1 and 2 are fast in dehydration, and step 3 rate-determining, while in l80 exchange step 1 is fast and step 2 is rate-determining. The olefin hydration rate, the alcohol dehydration rate, andthe 180 exchange rates all follow the H, function, and the Zucker-Hammetthypothesis leads to a dilemma concerning the stoicheiometric compositionof the respective transition states.Such a relation should be regardedrather as an indication that the activity coefficients of the transition statesfor addition, elimination, and exchange resemble those of oxoniumWhile the results are consistent with both schemes (a) and (b), the authors l9favour scheme (a) which involves encumbered carbonium ions and proton-olefin complexes.In the absence of solvent molecules with the necessary capacity forsolvation, the transfer of the proton from acid to base may require thedrafting of an additional molecule or molecules of acid to perform thefunction fulfilled by the hydrogen-bondingThe rate of addition of hydrogen chloride to isobutene in nitromethaneis of the first order in olefin and of the second order in hydrogen chloride.2aThe hydrogen chloride-catalysed component of radiochlorine exchange oft-butyl chloride is of first order in acid and in alkyl halide and is muchlarger than the corresponding component of elimination produced by tetra-ethylammonium chloride.24 Here hydrogen chloride acts as an electrophiliccatalyst and because of the suction of the thermodynamic control leads to2o R. W.Taft, jun., J . Amer. Chem. SOC., 1960, 82, 2956.21 H. van Looy and L. P. Hammett, J . Amer. Chem. SOC., 1959, 81, 3872; L. C.Smith and L. P. Hammett, ibid., 1950, 72, 301; R. Natoli (Reusch) Diss., Columbia,1955.22 Y . Pocker, J., 1958, 240.2s Y. Pocker, J., 1960, 1292.24 Y. Pocker, J . , 1960, 1972.2170 ORGANIC CHEMISTRY.overall exchange rather than to elimination. The transition state whenapproached from either direction has the same stoicheiometric composition :(CH&C=CH,,2HCI (CH&C+HCI,- (CH,),CCI,HCIThe introduction of deuterium during the exchange and addition is con-sistent with the view that step 1 is rate-determining in exchange irrespectiveof whether a free carbonium ion intermediate (scheme c) or the same in-volving ion-pairs (scheme d ) is postulated: 24IScheme (c): ButCl + HCI (But)+ + HCI,-- I22, (But)+ + (MeNO,) _.(CH,),C = CH, + H+ (MeNO,)- 23, Hf(MeN0,) + HCI,- =+= 2HCI + (MeNO,)-3Rates 3 > -3> -2> 2 > - I > II 2Scheme (d): ButCl + HCI __ (But)+HCI,- __ (CH,),C = CH, + 2HCI- I -2orIn non-aqueous solvents, stereospecific trans-addition of hydrogenchloride and bromide to certain tertiary olefrns has been found. Thehydration of the same olefins in aqueous media is non-stereo~pecific.~~ Invery weakly ionising solvents, e.g. , heptane, the hydrogen dichloride ion,HCl,-, forms a hydrogen bond with an additional hydrogen chloride mole-cule and the composition of the transition state for hydrogen chlorideexchange with t-butyl chloride 24 and of addition to isobutene 26 is :In contrast to behaviour in solvents of low ionising power, the gas-phaseelimination of hydrogen chloride from t-butyl chloride is not catalysed bythe acid produced; 27 but this acid can strongly catalyse the dehydration oftertiary alcohols in the gas phasesz8Moiseev and Syrkin claim 29 that quantum-mechanical calculationsindicate that the n-complex is less stable than the classical carbonium ion.The kinetics of olefin formation from 1-methylcyclohexanol and l-methyl-cyclohexyl acetate in S5-100~0 acetic acid in the presence of varyingamounts of sulphuric acid are consistent with a rate-determining productionof 1-methylcyclohexyl cation.30 The conversion of but-1-ene into but-2-ene,the hydration of but-1-ene to butan-2-01, the isomerisation of [4-14C]butan-2-01 to [l-14C]butan-2-ol, and the oxygen exchange of butan-2-[lsO]ol withwater are well explained by use of a single ionic intermediate; Manassen25 C.H. Collins and G. S. Hammond, J . Org. Chem., 1960, 25, 911; G. S. Hammondand C. H. Collins, J . Amer. Chem. SOC., 1960, 82, 4323.26 F. R. Mayo and J. J. Katz, J . Amer. Chem. SOC., 1947, 69, 1339.27 D. Brearley, G. B. Kistiakowsky, and C . H. Stauffer, J . Amer. Chem. SOC., 1936,58, 43; D. H. R. Barton and P. F. Onyon, Trans. Faraday SOC., 1949, 45, 725.28 A. Maccoll and V. R. Stimson, Proc. Chem. SOC., 1958, 80; J., 1960, 2836; K.G.Lewis and V. R. Stimson, J., 1960, 3087; R. A. Ross and V. R. Stimson, J., 1960,3090; V. R. Stimson and E. J. Watson, J., 1960, 3920.29 I. I. Moiseev and J. K. Syrkin, Doklad-y Akad. Nauk S.S.S. R., 1957, 115, 641.30 J . Rorek, Cnll. Czech. Chrm. Cowim., 1960, 25, 375.(CH3),C= CH2,3HCI (CH3),C+HZCI3- (CH3),CCI,2HCPOCKER THEORETICAL ORGANIC CHEMISTRY. 17 1and Klein 31 postulate that this intermediate is a planar carbonium ion whichis partially bound to a water molecule on each side of the plane. Thesolvolysis of t-butyl chloride in tritiated 90% formic acid occurs without theformation of C-T bonds in the alcoholic product up to the time at whichequilibrium is e~tablished.~~" This observation confirms the suggested 33explanation of the results of Kursanov, Setkina, and Bykova.= The isotopeeffect, kH/JZT, for solvent addition to propene in 90% aqueous formic at100" was found to be 4.5.32b It is suggested32b that the magnitude of thiseffect is largely determined by the zero-point energy of the H-X bond fromwhich the hydrogen ion (proton, deuteron, or triton) is transferred to olefin.cis-cyclo-alkene in acetic acid 100.4" are : cyclononene, 232 ; cyclodecene, 12.2 ;cycloundecene, 0.406 ; and cyclododecene, These equilibrationswere carried out in the presence of toluene-p-sulphonic acid as catalyst andproceed through carbonium ion intermediate~.~5 In the twelve-memberedring the equilibrium constant &/trans in the absence of solvent is0.67 & 0.08 at 25" 36 and in acetic acid it is 0.59 35 at the same temperature,indicating that, for this ring size, solvent effects are not paramount indetermining the position of equilibrium.Methylenecycloalkanes and1-methylcycloalkenes have been equilibrated at 25" in acetic acid con-taining toluene-$-sulphonic acid.37 In the nine- and ten-membered rings,the amounts of methylenecycloalkanes at equilibrium were too small fordetection.The first-order rate coefficients of elimination of hydrogen chloride fromcamphene hydrochloride in nitrobenzene are independent of the concen-tration of 2,6-lutidine, tribenzylamine, or tetrabutylammonium chloridewhen this concentration is low. At higher concentrations of the ammoniumchloride mild catalysis sets in, similar to that observed in other El elimin-ations in non-hydroxylic solvents.Protium and deuterium chloride stronglycatalyse the elimination, but because of the ready back-addition an earlyequilibrium is reached and the deuterium exchange becomes a direct conse-quence of elimination and back-addition. The transition states for thehydrogen chloride-catalysed elimination, exchange of deuterium or radio-chlorine, and rearrangement, of camphene hydrochloride in nitrobenzeneall have the same stoicheiometric composition but they differ in thetopology of their respective activated complexes. The transition stateof the hydrogen chloride-catalysed radiochlorine exchange is lower in freeenergy than that leading to elimination or deuterium exchange and this inturn is lower than that leading to rearrangement.3*TEDDER : AROMATIC COMPOUNDS.225(2)Substitution Reactions.--EZectrophiZic substitution. A considerablenumber of new electrophilic substitutions have been reported, one of themost interesting leading to the formation of aromatic aldehydes :lSTiCI4 or SnCI, H*OArH + C12CH*OR ______t ArCHCI.OR ___f ArCHO + ROH + HCIor AICIaThe direct introduction of an aminomethyl group into aromatic nucleican be achieved by two procedures which possibly involve the same inter-mediate~,~~ and a third process using N-chloromethylphthalimide and aH+ POCI,ArH + CH20 + RCN - ArCH,*NH*COR ArH + CH,(NHCOR),(144 (14b)zinc chloride catalyst-lb Iodination, which has been much studied in thepast, has now been developed into a practical reaction by using iodine andiodic acid and gives very high yields of aryl iodides.16 A number of newelectrophilic substitutions of aryloxide ions have been reported, althoughsome of these are probably more accuratey described as nucleophilic attackby the phenoxide ions (e.g., on arenesulphonyl azide l7 or mercaptoaceticacid 18).@-Naphthol ions are oxidised as well as substituted by tropyliumi0ns.1~13 A. Rieche, H. Gross, and E. Hoft, Chem. Ber., 1960, 93, 88.14 (a) C. L. Parris and R. M. Christenson, J . Org. Chem., 1960,25, 1888; (b) M. Ishi-15 S. E. Gornostaeva and K. A. Korev, Ukvain. Khim. Zhur., 1960, 26, 227.l6 H. 0. Wirth, 0. Konigstein, and W. Kern, Annalen, 1960, 834, 84.l7 J. M. Tedder and B. Webster, J., 1960, 4417.19 T.Nozoe, S. Ito, and T. Tezuka, Chem. and Ind., 1960, 1088.date, M. Sekiya, and N, Yanaihara, Chem. Ber., 1960, 98, 2898.F. M. Furman, J. H. Thelin, D. W. Hein, and W. B. Hardy, J . Amer. Chem. SOC.,1960, 82, 1450.REP.-VOL. LVII 226 ORGANIC CHEMISTRY.Last year it was reported that the isomerisation of the xylenes byaluminium chloride involved a 1,Z-shift. It has now been shown that theisomerisation of t-butyltoluene is entirely an intermolecular process, whileisomerisation of ethyl- and isopropyl-toluene proceeds by both mechanisms.20Hexaethylbenzene, when treated with acetyl chloride and aluminiumchloride, readily loses an ethyl group to yield pentaethylacetophenone ;methyl groups are less easily eliminated from hexamethylbenzene.21 Inanother acylation, namely, the synthesis of 2,6-dimet hylben~ophenone,~~the t-butyl group has been used as a blocking group.Nucleopkilic substitution.An important review on nucleophilic sub-stitution has been published.23 The von Richter reaction, in which anaromatic nitro-compound is converted into a carboxylic acid by treatmentwith alcoholic potassium cyanide, has been reinvestigated recently byBunnett and his co-workers.24 The combination of Bunnett's results withobservations (i) that the final carboxylic acid derives half its oxygen fromthe solvent 25 and (ii) that the nitrogen from the nitro-group and the nitrileare eliminated as molecular nitrogen,26 has clarified the reaction mechanism :NO,O H C+N-0' '0-NQco- IN=N()co,u+NZThe easy replacement of halogen atoms para to a diazonium group has beenfurther e~emplified,~' but somewhat surprisingly it has been found that theease of replacement by thiocyanate ions is in the reverse order, i.e.,I > Br > C1 > F, to that usually encountered in nucleophilic substitutions.28The formation of " dehydrobenzene " or " benzyne " intermediatesin nucleophilic substitution has been reviewed.29 The orientating effectsof other substituents in the molecule have been studied in the formationof benzyne from aryl bromides and lithium ~iperidide.~~ The writing ofthese intermediates with an acetylenic bond is in some ways misleadingand the actual overlap of the two non-bonded orbitals must be small.Inmany ways their behaviour is much more characteristic of a biradical.The formation of these species has previously been achieved by nucleophilicreagents; now three compounds have been shown to yield benzyne inter-mediates when heated or photolysed.The dipolar compound (4) is particu-larly interesting as it is relatively easy to prepare. It has been subjected toflash photolysis and the spectrum of a transient species has been detected;the end product was bi~henylene.~~ When heated with furan or withanthracene it yields 1,4-epoxy-lJ4-dihydronaphthalene (55%) or triptycene(30%) respectively.32 Pyrolysis of the compound (5) gave mercuric iodideand biphenylene, whilst photolysis in the presence of tetraphenylcyclo-pentadienone gave 1,2,3,4tetraphenylnaphthalene (25%) .% Pyrolysis ofthe silver salt (6) gave phenyl o-chlorobenzoate (60%), a result which isconsistent with a benzyne intermediate, but it must be added that attemptedreactions with furan or anthracene were unsuccessful in this case.% Severalconventional reactions with benzyne have been reported, an interestingobservation being that benzyne reacts with 2,5-dimethyl-2,4-hexadieneto yield 2,5-dimethy1-3-phenylhexa-l,4diene ; no Diels-Alder additionoccurred.%Homolytic substitution.The mechanism of arylation reactions hasreceived fresh consideration and it has been suggested that arylcyclohexa-dienyl radicals first formed (7) disproportionate to biphenyl and a 1,4-di-hydrobiphenyl (8) which is subsequently oxidised by the air.% This avoidsthe main problem of the previously acceptedcyclohexadienyl radical was assumed to bemechanism, in which the aryl-dehydrogenated by some un-known radical X.Substitution by the benzenesu&hamido-radical (ob-tained by pyrolysis of benzenesulphonyl azide 37) and by the trifluoromethylradical (obtained by photolysis of hexafluoroacetone %) has been studied.SCHEME A.lo4 W. Flaig, J. C. Salfeld, and A. Llanos, Angew. Chem., 1960, 72, 110.lo5 K. Alder, F. H. Flock, and H. Beumling, Chem. Ber., 1960, 93, 1896TEDDER : AROMATIC COMPOUNDS. 237been recognised; in one of these the aromatic compound is built from carbo-hydrate material, in the other from acetate. The carbohydrate route,possibly the more important, is much more fully understood and is summar-ised in the annexed scheme A.This pathway was discovered by B. D. Davisduring work with nutritionally deficient mutant strains of Escherichia C O Z ~ , ~ ~ ~and the early work has been reviewed by him.lo6 Important recent develop-ments include (i) the quantitative conversion of enolic pyruvate phosphate(41) and D-erythrose 4-phosphate (42) into shikimic acid (46),lo7 and (ii) theisolation of 3-deoxy-~-arabinoheptulosonic acid (43) .log Davis's originalwork connected this shikimic acid pathway with the naturally occurringaromatic amino-acids. Much recent work has gone into its connection withthe biosynthesis of lignin and the hydrolysable tannins.l1° Twostereospecific syntheses of shikimic acid have just been cornpleted.lll*7 CH,*C02H0 0 0 c c c-c cC Cp\ /+\ /a- 1 o c < ~ c o "?CI CI3 BaC033 CBr3N02--3.0 2 N O N 0 2 4 +HO\* OHi O"C) NO2OH3 BaCO, (Ob97*C)3 CBr3N02 (O-Ol*C)+NO2( 2*93*C) ( 9,02*C)SCHEME B.The intermediates in the acetate route have not yet been worked out.The main investigations in this field are those of Birch and his co-workers,and using tracers they have definitely established a head-to-tail linking ofacetate units in a variety of naturally occurring aromatic products.1l2Scheme B shows how, by using this technique, these workers were able toestablish a head-to-tail acetate linkage in griseofulvin (the figures in paren-theses represent the number of radioactive carbon atoms detected in eachlo6 B. D. Davis, Adv.Enzymol., 1955, 18, 24.lo7 P. R. Sprinivasan, M. Katagiri, and D. B. Sprinson, J. Biol. Chem., 1959, 234,713.lo* P. R. Sprinivasan, M. Katagiri, and D. B. Sprinson, J. Biol. Chem., 1959, 234,716.log K. Freudenberg, Nature, 1951, 183, 1152; S. N. Acerbo, W. J. Schubert, andF. F. Nord, J . Amer. Chem. Sac., 1960, 82, 735; K. Kratzl and H. Faigle, 2. Natztr-forsch., 1960, 15b, 4.E. Wenkert, Chem. and Ind., 1959, 906.l11 E. E. Smissman, J. T. Suh, M. Oxman, and R. Daniels, J . Amer. Chem. SOC.,1969, 81, 2909; R. McCrindle, K. H. Overton, and R. A. Raphael, J., 1960, 1560.Ila A, J. Birch, Fortschr. Chem. org. NaturstofJe, 1957, 14, 186; A. W. Johnson,Sci. Progr., 1960, 48, No. 189, 88238 ORGANIC CHEMISTRY.breakdown product).l13 This example dates from 1958 but it was chosenbecause of the great interest in griseofulvin this year (see above).Otherexamples of this technique reported during the last two years are the bio-synthesis of curvularin, cyclopaldic acid, and aromatic products from theAscomycete Daldinia c o r t c e n t r i ~ a . ~ ~ ~ The concept of head-to-tail acetatelinkage was first put forward by Collie fifty years ago, partly as a result ofhis studies on the reactions of P-polyketones. Birch and his colleagues havereinvestigated the condensations of heptane-2,4,6-trione and have cyclised8-phenyloctane-2,4,6-trione to yield the naturally occurring dihydro-pin0syloin.11~ Acetate is probably also involved in the biosynthesis ofanthraquinones and it has been shown to be incorporated in oxytetracycline(7 acetate units probably with a glutamate unit) and c-pyrromycinone(7 acetate units and one propionate unit) .l17 Naturally occurring tropolonesmay also be built up of head-to-tail acetate units together with one C, orformate unit.lls Glucose is also incorporated, but it is suggested that thisis after it has been degraded to C, and C, units.The carboxyl groups instipitatonic and stipitatic acid are derived from acetate.ug In generalmeta-dihydroxy-compounds are formed by the acetate route, while ortho-dihydroxy-compounds and carboxylic acids are derived from shikimic acid ;thus in the flavones and anthocyanins both routes are involved, yieldingseparately the two halves of the molecule.J. M. T.6. ALICYCLIC COMPOUNDSTHE first compound with interlocked rings has been prepared by cyclisationof the diester EtO,C*[CHJ,,*CO,Et in the presence of the deuterated cyclo-alkane C34H63D5 to yield an acyloin fraction containing about 1% of ther‘ catenane (1).Models indicate that cycloalkanes containing at leastfifty carbon atoms may exist as simple or knotted rings.The preparation of 3- and 4-membered carbocyclic rings has been re-viewed.2 Improved yields of cyclopropanes are obtained by the photo-chemical, rather than thermal , rearrangement of pyrazolines. Decom-position of the pyrazoline (2) yields l-methyltercyclopropane (3). ICHELSON : NUCLEIC ACIDS. 301Until recently the only hydrolytic enzyme of significance for distributionstudies of nucleotides in ribonucleic acids has been pancreatic ribonucleasewhich is specific for pyrimidine nucleoside-3’ phosphoryl-X linkages.Puri-fication of two other ribonucleases from takadiastase has increased consider-ably the possible approaches for analysis of ribonucleic acids. Ribo-nuclease T1 specifically cleaves internucleotide linkages between guanosine-3’phosphate and 5‘-hydroxyl groups of adjacent nucleotides, while ribonucleaseT2 shows a similar specificity for adenosine-3’ phosphoryl-X linkagesMAn extracellular ribonuclease from Bacihs subtilis has been crystallised ;its specificity is complementary to that of pancreatic ribonuclease, bothadenosine-3’ phospho- and guanosine-3’ phospho-diesters being cleaved.67Analysis of the products obtained by digestion of nucleic acids fromsome strains of tobacco mosaic virus with pancreatic ribonuclease indicatedaltered patterns of nucleotide sequence among different strains.@ Thedistribution of adenylic acid residues in tobacco mosaic virus ribonucleicacid has been examined by using a combination of takadiastase ribo-nuclease T1 and pancreatic ribonuclease : G9U GRibonucleic acid -+HO HO HO(C = cytosine, U = uracil, G = guanine, A = adenine, P = phosphate)Reddi has also used takadiastase ribonuclease T1 to estimate the distri-bution of guanylic acid in the same nucleic acid.Some 26.9% of the totalguanine was liberated as mononucleotide.70 However, experimental errormay be significant since Muira and Egami, using the purified enzyme, foundthat 55.7y0 of the total guanine was liberated as guanosine-3‘ phosphateand guanosine-2’,3’ cyclic phosphate (compared with a calculated 24.0y0 forrandom distribution) .71Physical chemistry.Wilkins and his colleagues have published detailsof an X-ray diffraction study of a crystalline form of the lithium salt ofDNA.72 Proton magnetic resonance studies of DNA do not indicate thepresence of ice-like domains of water molecules latticed about the macro-66 K. Sato-Asano, J . Biochem. (Jupan), 1959, 46, 31; M. Naoi-Tada, K. Sato-Asano, and F. Egami, ibid., p. 757; K. Sato-Asano and F. Egami, Nature, 1960,185,462.67 S . Nishimura, Biochim. Biophys. Acta, 1960, 45, 15.88 G. W. Rushizky and C. A. Knight, Proc. Nut. Acad. Sci. U.S.A., 1960, 46, 945;K.K. Reddi, ibid., 1959, 45, 293.6g K. K. Reddi, Biochim. Biophys. Ada, 1960, 42, 365.7O K. K. Reddi, Nature, 1960, 188, 60.71 K. Miura and F. Egami, Biochim. Biophys. Acta, 1960, 44, 378.78 R. Langridge, H. R. Wilson, C. W. Hooper, M. H. F. Wilkins, and L. D. Hamilton,J . MoZ. Biol., 1960, 2, 19; R. Langridge, D. A. Marvin, W. E. Seeds, H. R. Wilson,C. W. Hooper, M. H. F. Wilkins, and L. D. Hamilton, ibid., p. 38302 ORGANIC CHEMISTRY.molecule.73 A theoretical treatment of the hypochromic effect has beenpre~ented.'~ High-speed mixing, spraying, and even pipetting or similarturbulence cause a decrease in the sedimentation coefficient of DNA as aresult of hydrodynamic shear. Helical structure remains intact and frag-mentation by double-chain scission tends to give material of uniform mole-cular weight.75 Work on the electrometric titration of DNA continues; 76reversibility is obtained at -0.75".Sedimentation properties of DNA 77and a pH transition (in the absence of denaturation) in the sedimentationbehaviour 78 have been described, and dilution denaturation of DNA hasbeen re-in~estigated.7~ Both the density 80 and the configurational stability(as measured by thermal denaturation temperatures 81) are functions ofthe guanine-cytosine content in double-helical deoxynucleic acids. Strandseparation of transforming DNA by thermal denaturation and subsequentrenaturation by slow rather than rapid cooling gives up to 50% recoveredtransforming activity.82 Addition of denatured homologous (but notheterologous) %cild-type DNA during cooling increases biological activity.Kinetics of thermal degradation (followed by viscosity measurements)indicate single strands for both DNA and RNA under the denaturingconditions .%The physical properties of amino-acid acceptor RNA from E.c0ZiJ8*yeast,gS and mammalian liver g6 have received considerable attention.Molecular weights are probably about 25,000, that is approximately 70nucleotides per chain. Somewhat lower chain lengths (30-40 nucleotides)have also been reported; 87 discrepancies between physical and chemical(end-group analysis) molecular weights may be the result of aggregation.ELKS : STEROIDS. 313the 10~-fluoro-3-oxo-A~~4-compounds by this reagent 88 and into the corre-sponding lop-chloro-compounds by N-chlOro-amide~.~~~~~Various steroid olefins have been hydrated by successive treatment withdiborane and hydrogen peroxide ; the addition is in an anti-Markownikoffsense and is highly stereoselective. They include A6-,B0,Q1 and A’-compounds g2 (the last only in the 5cc-series 91), all the additions being sub-stantially from the ar-face.Application of the method to the enol acetateof a 17-oxo-steroid provides a convenient route to the 16ct,17p-di01.~~The rates of reduction of steroid ketones with sodium borohydride inpropan-2-01 decrease in the order: 3-oxo-As- > 3-oxo-A8(14)- > 3-oxo-5p- >3-oxo-5ct- > 6-0x0- > 7-OXO- > 3-oxo-A4- > 12-0x0- > 17-oxo- > 20-oxo- > 1 ~ - o x o - . ~ ~ Lithium tri-t-butoxyaluminium hydride is more stereo-specific in the reduction of ketones than is lithium aluminium hydride orsodium bor~hydride.~~Continuing their study of long-range effects,g6 Barton and his co-workershave investigated the rates of reaction of 3-oxo-steroids with benzaldehydein presence of base.27 Electrostatic effects of polar groups seem to be ofminor importance, as is that of “ axial buttressing.” Greatest effects, whichare cumulative, result from introduction of double bonds, either endo- orexo-cyclic, and the authors argue that they are produced by transmissionof bond distortion through the rings.A similar explanation is advanced toaccount for the effect of unsaturation in rings A and B upon the rate ofsolvolysis of 17 p-toluene-fi-sulphonate~.~~ On the other hand, transmissionof inductive effects seems responsible for the effect of different esterifyinggroups on the rate of addition of bromine to 3p- and 17P-hydroxy-A5-corn pound^.^^HONEYMAN: CARBOHYDRATES. 333from D-eryt~ro-L-nzanrto-octose through reaction with nitromethane.4 Bothgave crystalline lactones and phenylhydrazones and one, D - W ~ ~ ~ P Z O - L -galacto-nonose, is apparently identical with the product obtained fromD-mannose by successive cyanohydrin reactions.45OEsidation.-A kinetic study of the oxidation of D-glUCOSe by an alkalinesolution of cupric picolinate at 25" has revealed that there is an inductionperiod after which the reaction is of substantially zero order with respect tocupric ion and of first order with respect to ~-glucose.~6 Oxidation ofD-glucose by aqueous bromine has received considerable attention.In onepaper 47 the authors claim to have established that the concentrations of Bra-and hypobromous acid make negligible contributions : the marked depen-dence of the reaction rate on pH was believed to show that an anionic formis oxidised much more rapidly than the sugar itself; and supporting evidencehas been presented.& However, experiments done in aqueous solutionsbuffered at pH 5 have shown that the rate constant for the oxidation islinearly dependent on bromine concentration and, when extrapolated to zerobromine concentration, becomes almost identical with the polarimetricallydetermined rate constant for the conversion of a- into p-D-glucose, with thesame temperature-dependence between 0" and 25".The major reaction isthe conversion of the a- into the P-anomer which is rapidly oxidised directlyto 8-gluconolactone. Formation of a conjugate acid from P-D-glUCOSe andmolecular bromine is postulated for the first step of the oxidation, beingfollowed by slow elimination of hydrogen bromide.49 Pentoses (exceptD-1yXOSe) and other hexoses in which the concentration of the acyclic formis unimportant are also oxidised in theWhen oxygen was passed through aqueous solutions of D-glucose sub-jected to ultraviolet light, degradation occurred with the formation of,mainly, arabinose and small aldehydic molecules.51 However, y-irradiationof oxygenated D-mannose solutions gave D-mannuronic acid, D-arabinose,D-erythrose, and smaller fragments.The primary reactions involvedoxidations a t C(s> and C(ll, and scissions between C(0 and C(,) and betweenand with simultaneous conversion of the hexose into three equalfragments .61Degradation.-Improved methods for degrading D-glucose containing 14Catoms allow the radioactivity of each carbon atom to be determined.52Specifically labelled D-glucose has been converted into the correspondinglylabelled D-fructose (75% yield) by reduction with sodium borohydridefollowed by an enzymic oxidation.%The hydrogenolysis of methyl a-D-mannoside at 180" with copper44 J. C.-Sowden and D. R. Strobach, J . Aaner. Chem. SOC., 1960, 82, 956.45 E. Fischer and R. Hagenbach, see E.Fischer, " Untersuchungen uber Kohlen-hydrate und Fermente, " Julius Springer, Berlin, 1909, 582.46 B. A. Marshall and W. A. Waters, J., 1960, 2392.47 B. Perlmutter-Hayman and A. Persky, J . Amer. Chem. Soc., 1960, 82, 276.4* B. Perlmutter-Hayman and A. Persky, J . Amer. Chem. Soc., 1960, 82, 3809.49 I. R. L. Barker, W. G. Overend, and C. W. Rees, Chem. and Ind., 1960, 1297.50 I. R. L. Barker, W. G. Overend, and C. W. Rees, Chem. and Ind., 1960, 1298.81 G. 0. Philips and G. J, Moody, J., 1960, 3398.j a P. Kohn and B. L. Dmuchowski, J . Bid. Ckem., 1960, 235, 1867.53 J. A. Muntz and R. E. Carroll, J . Biol. Chew., 1960, 235, 1258334 ORGANIC CHEMISTRY.chromite as catalyst gave a mixture of isomeric glycosides, but notably thetalopyranoside (27% yield) , which was also obtained from other hexo-pyranosides.The p-anomers are more stable under these conditions,especially the glucoside and the mannoside which were recovered sub-stantially unchanged. The pentosides were more readily converted intotetrahydropyrandiols. Use of higher reaction temperatures led to a mixtureof stereoisomeric 1,5-anhydro-4-deoxy-~-hexitols from methyl Cc-D-@UCO-side.% Hydrogenation of sucrose gave mainly glycerol and propane-1,2-di01.~~ Theoretical consideration has been given to the action of thecat a1 ys ts. 56Treatment with lime-water of 4-O-substituted D-glucoses yields mainlyD-glucoisosaccharinic acid but with sodium hydroxide fragmentation pre-dominate~.~' The 4-O-substituted glucoses are degraded mainly to 3,443-deoxy-3-oxo-~-fructose (4) which has been isolated also after the action ofsodium hydroxide on maltose5s or of air-free potassium hydroxide oncellobio~e.~~ Compound (4) undergoes a benzilic acid rearrangement in theCH,*OH I c=o1 c=oII CH2 II IY2HCHs-7-OHH-C-OHH-C-OH H-C-OHCH,-OH(4)CH,*OH(5)presence of calcium hydroxide, Sodium hydroxide, however, causes muchfragmentation with the formation of acid products, including glycollic, Py-dihydroxybutyric , and formic acid.58 The wketo-aldehyde, S-deoxy-~-glucosone, also isolated, has been shown to rearrange rapidly in alkalinesolutions to give D-glucometasaccharinic acids.60 An excellent method forpreparing 3-deoxyhexosones has been described.61 Calcium.ions have beenshown to be particularly effective in catalysing the rearrangement of glyoxalin aqueous sodium hydroxide.62 The " 01 "-D-glucosaccharinic acid is 2-C-methyl-D-ribopentonic acid (5) .63 Kenner and Richards's work indicates 64that the main product from treatment of l-0-methyl-L-sorbose with lime-water would be expected to be 2-C-methyl-~-xyZo- or -L-Zyxo-pentonic acidwhereas the enantiomorph of (5) was actually isolated.= This may be the54 P.A. J. Gorin, Canad. J . Chem., 1960, 38, 641.55 C. Boelhouwer, D. Korf, and H. I. Waterman, J . Appl. Chem., 1960, 10, 292.56 A. A. Balandin and N. A. Vasyunina, Zhur. $2. Khim., 1959, 33, 2490.57 D. O'Meara and G. N. Richards, J., 1960, 1924.58 D. O'Meara and G. N. Richards, J., 1960, 1932.69 R.L. Whistler and J. N. BeMiller, J . Amer. Chem. Soc., 1960, 82, 3705.6o D. O'Meara and G. N. Richards, J . , 1960, 1938.61 E. F. L. J. Anet, Austral. J . Chem., 1960, 13, 396; J. Amer. Cham. Soc., 1960,62 D. O'Meara and G. N. Richards, J., 1960, 1944.63 1. C. Sowden and D. R. Strobach, J . Amer. Chew. Soc., 1960, 82, 3707.65 J. C. Sowden and I. I. hlao, J . Org. Chem., 1960, %, 1461.82, 1502.E.g., J . Kenner and G. 3. Richards, J., 1955, 1810HONEYMAN : CARBOHYDRATES. 335result of fragmentation followed by recombination or of an initial inversionat The pre-sence of borate in the solution greatly increases the yield of ketose obtainableby the treatment of aldose with dilute alkali.66 The best conditions havebeen established for the production of D-arabonic acid (about 75% yield) bythe action of oxygen on solutions of D-glUCOSe or D-fructose in aqueous oraqueous-methanolic potassium hydroxide.67Aceta1s.-The condensation of D-mannitol with 1,l ,l-trifluoroacetone inthe presence of sulphuric acid gives a mixture of the bis- and tris-derivatives.Two crystalline isomers of 1,2 : 5,6-bis-O-trifluoroisopropylidene-~-mannitolwere isolated.The 1,3-dioxolan rings in these compounds are exception-ally stable to acids and other reagents presumably owing to the stronglyelectrophilic trifluoromethyl group.68 The action of methanolic hydrogenchloride on 2,4-O-ethylidene-~-erythrose gave methyl 2,3-@ethylidene-p-D-erythroside, the isomerisation leading to the formation of the stablesystem of fused five-membered rings.69The mechanism by which boron trichloride removes substituent acetalgroups from hexitols depends on its co-ordination with an oxygen atom ofthe acetal ring, followed by ring-opening to give the a-chloro-etherThis reagent has been applied to several acetals; 71 it is also able to de-methylate many methyl ethers of sugars.72Deoxy-sugars.-Triphenyl phosphite methiodide 73 has been used to con-vert di-O-isopropylidene-D-glucose into the 3-deoxy-3-iodo-compound whichgave, on hydrogenation over Adams catalyst followed by acid hydrolysis,3-deoxy-~-ghcose as a syrup contaminated with a little D - ~ ~ u c o s ~ .~ ~ Twonew crystalline forms of 3-deoxy-~-glucose have been isolated. These areprobably the p-pyranose and the a-furanose m~dification.~~ Treatment ofan ether solution of methyl 2,3-anhydr0-4,6-O-benzylidene-cc-~-mannosidewith lithium aluminium hydride followed by hydrolysis gave 3-deoxy-~-inannose for the first time in crystalline form.76 Hydrogenation in the pre-sence of Raney nickel converted methyl 3,4-anhydro-a-~-galactoside into amixture from which methyl 4-deoxy-~-glucoside was isolated. Hydrolysisgave crystalline 4-deoxy-~-glucose.Hydrogenation over carefully purifiedRaney nickel gave from 5,6-anhydro-1,2-0-isopropylidene-a-~-glucose amixture which was readily fractionated by gas chromatography into 6-deoxy-(67%) and 5-deoxy-derivative (33%) ; the latter was obtained crystalline.77,411 the monodeoxy-D-glucoses are thus now available in crystallinecondition.via the 3,4-enediol followed by the usual rearrangement.fi6 J.F. Mendicino, J . Amer. Chem. Soc., 1960, 83, 4975.67 J. Dubourg and P. Naffa, Bull. Soc. chim. France, 1959, 1353.68 E. J. Bourne, A. J. Huggard, M. Stacey, and J. C. Tatlow, J., 1960, 2716.69 C. E. Ballou, J . Amer. Chsm. Soc., 1960, 82, 2585.70 T. G. Bonner and N. M. Saville, J., 1960, 2851.71 T. G. Bonner, E. J . Bourne, and N. M. Saville, J., 1960, 2914, 2917.72 T. G. Bonner, E. J. Bourne, and S. MacNally, J.. 1960, 2929.7 3 S. R. Landauer and H. N. Rydon, J., 1953, 2224.7 4 J. B. Lee and M. M. El Sawi, Chem. and Ind., 1960, 839.7.j E. F. L. J. Anet, Chem. and Ind., 1960, 345.7 6 G. Rernbarz, Chem. Ber., 1960, 93, 622.7; E. J. Hedgley, 0. 1CIQ&z, 1%'.G. Overend, and R. Rennie, Chewz. aizd Ind., 1960,938336 ORGANIC CHEMISTRY.Sulphur-containing Derivatives-Episulphides have been made fromsuitably substituted hexose or hexitol 5,6-ditoluene-~-sulphonates byreaction with potassium thiolacetate (which replaces the 6-tosyl by anacetylthio-group) and then sodium methoxide in methanol. An alternativemethod, giving lower yields of the 5,6-episulphide, consists of treating a5,6-epoxide with thiourea or an alkali-metal thiocyanate. The replacementinvolves inversion of c o n f i g ~ r a t i o n . ~ ~ ~ ~ ~ Reduction of the 5,6-episulphideswith lithium aluminium hydride gave the 5,6-dideoxy-5-mercapto-derivative,whereas treatment with potassium hydroxide and carbon disulphide gavethe 5,6-dideoxy-5,6- (thiocarbonyldit hio) -derivat ives.When the latter com-(Ts = toluene-p-sulphonyl)pounds were similarly obtained from 5,6-epoxides the reaction was accom-panied by inversion of configuration 78 although it had previously beenassumed that inversion did not occur.8o Lithium aluminium hydride con-verted these compounds into the corresponding dithiols81When 1,Z-anhydro-a-D-glucopyranose was treated with hydrogensulphide in dimethylformarnide, a mixture of l-thio-D-glucoses wasformed. This was oxidised by hydrogen peroxide to di-D-glUCOpYranOSyldisulphide . 82Treatment of D-glucose with aqueous sodium hydrogen sulphite at 100"for 8 hours gave unchanged glucose fa%), gluconic acid (7.6%), and glucose6-sulphate (1 1-5%, as crystalline brucine salt).D-Galactose 6-sulphate wasobtained in the same way. Treatment of D-glucose with sodium dithionitegave an even higher yield (25%) of the 6 ~ u l p h a t e . ~ ~ The importance ofthese reactions in preventing foods from browning is discussed.84In the Koenigs-Knorr synthesis of disaccharides better yields haveresulted from using an acyclic sugar derivative because of reduced sterichindrance.8j For this reason the use of dimethyl thioacetals for makingpure acyclic derivatives has been investigated.86 Other preparations andreactions of sugar mercaptals have also been re~orded.~'and ofperiodic acid 89 on sugars has been reviewed.with periodate in very dilute solutions has been found by polarographicmethods to obey the second-order law.Neither the decomposition of thecyclic intermediate nor the direct reaction of diol with periodate is rate-determining. The tkreo-isomers are oxidised faster than the erythro-onesbut there is no simple relation between the rates of oxidation and the sizeof R and R'.90Potassium periodate-cuprate is suggested for use in paper chromato-graphy as a sensitive reagent for detecting sugars and other oxidisablecorn pound^.^^Periodate oxidations proceed slowly in dimethylformamide unless about50% or more of water is present. This may be a useful solvent for studyingkinetically oxidations which are otherwise inconveniently fast .92Oxidation of methyl D-glUC0- or D-galacto-furanoside at about 5" with onemolecular proportion of sodium periodate breaks the molecule between C(5Jand C(61 giving methyl D-XJ~O- or L-arabino-furanosides respectively afterreduction of the product.93 A simplified preparation of L-xylose from sor-bitol has been described.94Periodate oxidation of 2-deoxy-D-glucose , -maltrose, or -D-galactoseinvolves the rapid consumption of one molecular proportion of oxidant,with the production of the same dialdehyde, arising from fission between C,,and C(,). Finally six mol.of periodate are used, leading to the formationof five mol. of formic acid and one of f~rmaldehyde.~~By using one mol. (or less) of periodic acid it has been shown that D-fructose undergoes two reactions, one giving formaldehyde and arabonicacid by fission between Co) and C(z), and the other yielding glyoxylic acid andcrythrose by fission between C,,, and G(3).g6Periodate attacks preferentially the glucose residue in sucrose whereaslead tetra-acetate oxidises first the glycol group at and C(,) in the fructo-furanose part.The different mode of reaction may be due to different stericrequirements of the reagents or relative ease of the decomposition of theGlycol-cleaving Reagents.-The action of lead tetra-acetateOxidation of open-chain diols [general formula, R*CH(OH)*CH(OH)*K'96 P. Fleury, J.-E. Courtois, and L. Le Dizet, Bull. SOC. chirn. Fyartce, 1959, 1664.1958, 23, 1237338 ORGANIC CHEMISTRY.cyclic complexes produced rather than to any fundamental differences inthe reaction mechanism^.^'Methylation studies of the ‘‘ dialdehydes ” obtained by the periodateoxidation of methyl 6-O-methyl-a-~-galactopyranoside and methyl p-L-arabinopyranoside have shown that the compounds react in the hemialdalform -CH(OH)-O-CH(0H)-.The “ dialdehyde ” from methyl a-D-glUCO-pyranoside, however, may react in other forms because of the free hydroxylgroup on the primary carbon atom. The two crystalline products isolatedas a result of treatment of the “ dialdehyde ” with methyl iodide and silveroxide have been shown to be (6) and (7) derived from (8) and (9).98t tThe product obtained by the periodate oxidation of methyl 4,6-0-benzyl-idene-a-D-glucoside has been shown to react as a dialdehyde or as a hemi-alda1.99 Further examination has shown that treating the oxidation productwith phenylhydrazine gives methyl 4,6-0-benzylidene-3-deoxy-3-phenylazo-a-D-glucoside (-alloside) ; this has been reduced to the 3-amino-3-deoxy-~-glucose (kanosamine) derivative in good yield.lW Other compounds existingas the hemialdal include 2-(4-carboxy-5-methyl-2-furyl)diglycollic aldehydeand the corresponding 4-acetyl compound.99Treatment of the dialdehydic oxidation products with nitromethane inmethanol containing sodium methoxide leads to re-formation of a ringstructure containing a deoxy-nitro-grouping which is readily reduced togive an amino-deoxy-sugar.Examples include the preparation of methyl3-amino-3-deoxy-~-~-glucopyranoside from methyl p-D-glucopyranoside orp-D-ribopyranoside.lO1 Similarly lzvoglucosan has been converted into amixture of crystalline 3-amino-l,6-anhydro-3-deoxy-p-~-gulose, -p-D-altrose,and -p-D-idose.lo2Ethers.-Evidence is now available to show that in cellulose and methyla-D-glucopyranoside the hydroxyl group on Co is the most acidic.To con-firm this both compounds have been converted into monosodio-derivativesand then treated with methyl iodide: the products were hydrolysed and the97 A. K. Mitra and A. S. Perlin, Canad. J . Chem., 1959, 37, 2047.98 I. J. Goldstein and F. Smith, J . Amer. Chem. SOC., 1960, 82, 3421.99 R. L. Colbran, R. D. Guthrie, and M. A. Parsons, J., 1960, 3532.l o o R. D. Guthrie, Proc. Chem. SOC., 1960, 387.lo1 H. H. Baer, Chew Ber., 1960, 93, 2865.102 A. C. Richardson and (the late) H. 0. L. Fischer, Proc. Chem. Soc., 1960, 341HONEYMAN : CARBOHYDRATES. 339sugars separated and identified.Although substitution is far from exclusivethe 2-O-methyl-~-glucose was obtained in highest yield, with the 6-methylether next.lo3 Methods have been given for the synthesis of many referencecompounds including 5-O-methyl-~-arabinose lo4 (found as a hydrolysisproduct of methylated wheat-bran hemicellulose) and crystalline 2,3-di-0-methyl-~-arabinose.l~~ Chemical synthesis of 4-O-methy1-~-glucuronic acidhas proved to be unexpectedly difficult. Methyl 2,3-di-O-benzyl-4-0-methyl-a-D-glucoside is easily made but it is not oxidised by permangan-ate; 106 debenzylation followed by oxidation with sodium nitrite in phos-phoric acid107 and then hydrolysis gave a mixture of sugars from which4-O-methyl-~-glucuronic acid was isolated in low yield.lO6 A similar syn-thesis of methyl 4-O-fnethyl-~-~-glucuronoside methyl ester and crystallineamide has also been described.los The tetrabenzyl ether of methyl a-D-glucopyranoside has been made under substantially dry conditions, namely,by using benzyl chloride and potassium hydroxide at 100" for five hours.logEsters.-Acetylation of aldonic acids often gives poor yields but a generaldirect method giving 70-80%- yields is now available.ll0 Acetylation ofD-glucose with acetic anhydride in aqueous solution at pH 8-10 has givena high yield of D-glucose 1,3,4,6-tetra-acetate; D-mannose tetra-acetate, andsorbitol and D-mannitol penta-acetates were similarly obtained.111 A goodpractical process 112 for deacetylating sugar acetates is a modification of theZemplh method.Deacetylation of p-D-glucopyranose penta-acet at e withcold aqueous potassium hydroxide in acetone gave some a-D-glUCOSe 6-acetate. 113Alkyl or aryl chloroformates react with carbohydrates in the presence ofaqueous alkali to give O-alkyl(or ary1)oxycarbonyl derivatives 114 or cycliccarbonates when steric factors are fa~ourab1e.l~~ Methyl a-D-manno-pyranoside gave a 75% yield of a methyl di-0-benzyloxycarbonyl-a-D-mannoside carbonate which was hydrogenated to give methyl cr-D-mannO-pyranoside 2,3-carbonate. A similar compound was not obtained from theglucoside, but methyl a-D-galactoside gave a 3,4-carbonate.l16 Thus a five-membered cyclic carbonate is readily formed if cis-hydroxyl groups areavailable on adjacent carbon atoms although cyclic carbonates have beenmade from 1,2-, 1,3-, and 1,4-diols.l17 In an attempt to make a-D-ribosylderivatives by having a non-participating group at C(2! some 2,3-carbonatesof n-ribose have been made.Under certain conditions those of D-ribo-103 R. W. Lenz, .J. Amer. Chem. SOC., 1960, 82, 182.104 G. G. S. Dutton, Y . Tanaka, and K. Yates, Caizad. J . Chem., 1959, 37, 1955.105 J. P. Verheijden and P. J. Stoffyn, BUZZ. SOC. chzm. belges, 1959, 88, 699.106 W. D. S. Bowering and T. E. Timell, Canad. J . Chem., 1960, 38, 311.107 S. Machida, N. Uchino, and M. Inano, BUZZ. Fac. Text. Fibers, Kyoto Univ.,108 F. Leitinger, Monatsh., 1960, 91, 620.109 0. T. Schmidt, T. Auer, and H. Schmadel, Chem.Ber., 1960, 93, 556.110 R. Barker, J . Org. Chem., 1960, 25, 1670.111 V. Prey and A. Aszalos, hfonatsh., 1960, 91, 729.112 D. H. Leaback, J , , 1960, 3166.113 Y. 2. Frohwein and J. Leibowitz, Nature, 1960, 185, 153.114 C. F. Allpress and W. N. Haworth, J., 1924, 125, 1223.115 G. R. Barker, I. C. Gillam, and J. W. Spoors, Chem. and Ind., 1956, 1312,116 I,. Hough and J. E. Priddle, Chem. and In.d., 1959, 1600.117 S . Sarel, L. A. Pohoryles, and R. Ben-Shoshan, J . Org. Chem., 1059, 24, 1873.1956, 1, 459340 ORGANIC CHEMISTRY.furanose (but not those of D-ribopyranose) were found to be useful for thepurpose. The absence of a participating group at C(a) resulted in replace-ments at C(0 which are sterically less specific, the proportions of the anomersobtained depending on the configuration at C,,, the reaction conditions, andthe nature of the incoming group.l18The four tribenzoates of the pyrqnose and furanose forms of 2-deoxy-D-ribose have now been prepared in pure condition.llg Brief treatment ofp-L-arabinopyranose tetrabenzoate with hydrogen fluoride gave L-arabino-pyranosyl fluoride tribenzoate but if the reaction time was extended thenp-L-ribopyranosyl fluoride 3,4-dibenzoate was obtained.120 This unusualreaction may explain why many acylated glycosyl fluorides have been ob-tained in low yields.Another anomalous transformation occurred duringthe benzoylation of p-D-ribopyranosyl fluoride 3,4-dibenzoate, the productbeing a tribenzoate of D-ribofuranosyl fluoride.121Methane- or toluene-#-sulphonyloxy-groups attached to secondary carbonatoms within a sugar ring have low reactivity in SN2 replacement reactions.Thus sodium iodide does not react with isolated ones even under drasticconditions and when sodium hydroxide does react it causes simple hydrolysiswithout inversion.Ammonia or, better, hydrazine has been found to beeffective for converting 1,2 : 5,6-di-isopropylidene-~-glucose 3-toluene-9-sulphonate into 3-amino-3-deoxy-1,2 : 5,6-di-isogropylidene-~-allose.~~~Sodium benzoate in boiling dimethylformamide, successfully used to replacewith inversion a sulphonate group by benzoate on a secondary carbon atomin a ~ide-chain,~~~ has now been used (at 140" for a day) to convert methyla-D-galact oside 2,3-dibenzoat e 4,6-dit oluene-9-sulphonate into crystallinemethyl a-D-glucoside 2,3,4,6-tetrabenzoate.l= Sodium benzoate in di-methylformamide is a powerful nucleophilic reagent but the displacementreaction is helped because the departing group is leaving from an axialposit ion.When di-isopropylidene-wgalact ose 6-met hanesulphonat e washeated at 150" with potassium fluoride in methanol containing a little watera mixture of 6-deoxy-6-fluoro- and 6-O-methyl-di-isopropylidene-~-galactosewas obtained.125HONEYMAN : CARBOHYDRATES. 347pectin, was found to be 17, in good agreement with results from othermethods.200Cellulose.-Treatment of cellulose with ethylamine at -5" or ethylene-diamine at 20°, followed by removal of the amine with ice-water, resulted inappreciable reduction in crystallinity and in the size of the crystallites; hotwater causes recrystallisation to occur.2o1 Like other oxidised celluloses,that produced by periodate oxidation is very sensitive to attack by alkali.However, it is resistant to acid-hydrolysis, the resistance increasing with thedegree of oxidation, possibly because cross-links are formed between thealdehyde groups and hydroxyl groups in adjacent molecules. However, theborohydride-reduced oxycellulose is readily hydrolysed by acid because of itsopen, accessible structure.202 Deuterium- 203 and tritium-exchange 204 havegiven information about the accessibility of cellulose to water.Cellulosesulphates have been made by treating cotton linters with liquid sulphurdioxide containing sulphur trioxide, chlorosulphonic acid, or sulphuric acid.205A polyglucose (probably cellulose) sulphate has been isolated from the snailBusycon.206Alginic Acid.-Alginic acid isolated from algae that have been storedhas a simpler structure than that of the acid obtained from fresh weed be-cause of fermentations that occur.It is claimed that xylose units are presentas well as mannuronic acid residues.207 The presence of L-guluronic acid inalginic acid 208 has been amply confirmed.209 The partial hydrolysateobtained from alginic acid has been found to contain two disaccharides anda trisaccharide, all containing both D-mannuronic and L-guluronic acid."OThis shows that the two hexuronic acids are combined in alginic acid.Although D-mannuronic acid is readily converted by epimerisation on C(5)p-IC(0 H)*C H , a 0 H IH-C-OH IC02- (15)into L-guluronic acid under neutral conditions 211 or in aqueous solutioncontaining calcium carbonate 210 no such change was possible under the200 I.J. Goldstein, J. K. Hamilton, and F. Smith, J . Amer. Chem. SOG., 1959, 81,201 N. Komatsu and H. Sakata, J . Chem. SOC. Japan, Ind. Chem. Sect., 1960, 63, 1050.202 E. H. Daruwalla, P. J. Kangle, and G. M. Nabar, Textile Res. J., 1960, 30, 469.!203 J. L. Morrison, Nature, 1960, 185, 160.204 A. R. G. Lang and S. G. Mason, Canad. J . Chem., 1960, 38, 373.206 R. Asami and N. Tokura, J . Chem. SOC. Japan, I n d . Chem. Sect., 1959, 62, 1593.206 J. W. Lash and M. W. Whitehouse, Biochem.J., 1960, 74, 351.207 R. Massoni and G. Duprez, Chimie et Industrie, 1960, 83, 79.208 F. G. Fischer and H. Dorfel, 2. Physiol. Chem., 1955, 302, 186.209 D. W. Drummond, E. L. Hirst, and E. Percival, Chem. and INd., 1958, 1088;R. L. Whistler and I<. W. Kirby, 2. physiol. Chem., 1959, 314, 46; A. Haug, Acta Chem.Scand., 1959, 13, 1250.6252.2lO D. I. Vincent, Chem. and Ind., 1960, 1109.211 F. G. Fischer and H. Schmidt, Chem. Ber., 1959, 92, 2184348 ORGANIC CHEMISTRY.conditions actually used. Partial hydrolysis of alginic acid gave dimeric andtrimeric uronic acids which were apparently assumed to contain D-ma-nuronic acid only.212 Alkaline degradation of alginates 213 follows theexpected course, giving 3-deoxy-2-C-hydroxymethylpentanedioates (15).Starch and Glycogen.-X-Ray diffraction studies have shown that air-drypotato starch contains about 21% of crystalline material; the proportionincreases somewhat when the starch is moistened or subjected to mild acid-hydrolysis.214Sucrose monostearate forms insoluble complexes with starch and itsfractions; with amylose about 80% of the polysaccharide is precipitatedwhereas with amylopectin it is only about 11 yo.With wheat-starch granulesa surface complex is obtained which may prevent the passage of water. Thismay explain why the monostearate acts as an anti-staling agent in bread.215Ionic surface-active compounds which also give complexes with starch in-clude sodium dodecyl sulphate 216 and cetyltrimethylammonium bromide.217The molecular weights of crystalline amyloses from rice starches range from29,000 to 48,000 depending on the variety.21s Investigation of the inter-action of starch with iodine in potassium iodide solutions has shown thateven small molecules (nonasaccharides) give complexes.21B An interestingreview of the molecular properties of the amylose and amylopectin hasappeared ; methods of extraction and purification are also discussed.220Kinetic studies of the hydrolysis of linear starch fractions by P-amylaseshow that the binding affinity and the velocity of reaction increase withincreased size of the substrate molecule.221 It has been claimed fromstudies on starch granules with a- and @-amylases that the outer chains ofamylopectin are on the surfaces of the granules and therefore readily avail-able for enzyme attack.222 Barley, soyabean, and almond emulsin p-amylaseall contain traces of a-amylase, which explains the Z-enzyme type of activityof these preparations.223 The action of Z-enzyme on amylose and amylo-pectin is indistinguishable from that of =-amylase, yet they are differentbecause Z-enzyme does not attack glycogen.224 Amylose is converted bysalivary a-amylase into maltose and maltotriose, the latter being furtherdegraded to maltose and glucose,225 but amylopectin is not completelydegraded because the enzyme does not attack certain linkages near thebranch points.226 The limit dextrins produced by the action of rabbit-212 G.Jayme and K. Kringstad, CJaem. Ber., 1960, 93, 2263.213 R.L. Whistler and J. N. BeMiller, J . Amer. Chem. Soc., 1960, 82, 457.21.1 C. Sterling, StcZrke, 1960, 12, 182.213 E. J. Bourne, A. I. Tiffin, and H. Weigel, J . Sci. Food Agric., 1960, 11, 101.216 T. Takagi and T. Isemura, Bull. Chem. SOC. Japan, 1960, 33, 437.217 M. M. Fishman and R. S. Miller, J . Colloid Sci., 1960, 15, 232.218 Hsiu Ying Tsai, A. T. Phillips, and V. R. Williams, J , Agric. Food Chem., 1960,219 J. A. Thoma and D. French, J . Amer. Chem. Soc., 1960, 82, 4144.220 C. T. Greenwood, Stdrke, 1960, 12. 169.221 J. A, Thoma and D. E. Koshland, jun., J. Biol. Chem., 1960, 235, 2511.212 p. Nordin and Y. S. Kim, J . Amer. Chem. SOC., 1960, 82, 4604.223 W. L. Cunningham, D. J. Manners, A. Wright, and (in part) I. D. Fleming, J.,224 W.Banks, C. T. Greenwood, and I. G. Jones, J., 1960, 150,225 G. J. Walker and W. J . Whelan, Biochem. J., 1980, '46, 267.~6 p. J. p. Roberts and W. J. Whelan, Biochem. J., 1960, 76, 246.8, 364.1960, 2602HONEYMAN : CARBOHYDRATES. 349muscle phosphorylase on glycogen and amylopectin have side-chains of(probably) four glucoseThe reserve carbohydrate of the green seaweed Caulerpa jfilifoymis isvery similar to the mylopectin of land plants.22s The protozoon ChiZomonas9aramecium grown on an acetate-containing medrum synthesises a starchcontaining 45% of amylose of rather low molecular weight and iodine-binding power.229Hemicelluloses.=O-The xylan of cocksfoot grass (Dactylis glomerata) hasa main chain of 1,4-linked P-D-xylopyranose units to which side-chain end-groups of L-arabinofuranose and 4-O-methyL~-glucuronic acid residues areattached (to Cto and Ct21.respectively).231 The xylan of bamboo stalks alsohas arabinofuranose units as side-chains.B2 A hemicellulose from Scotspine (Pinus szlvestris L.) has a main-chain of 1,4-P-D-XylOPyranOSe units sub-stituted at C(@ of about one-fifth of the units with 4-O-methyl-~-g~ucuronicacid and at Ct3) of about one-seventh of the units with L-arabinofuranose.=In methylation studies it has been found that the hydroxyl group on C(,)of the xylose units of esparto xylan is the less reactive.= The hemicellulosefraction of alfalfa (Medicago sativa) hay has received preliminary study.%There are many reports that 2-0-(4-~-rnethyl-a-~-g~ucuronosyl) -~-xylose hasbeen obtained by the partial hydrolysis of h e r n i c e l l u l o ~ e s .~ ~ ~ ~ Suitableisolation procedures give birch-wood hemicelluloses containing the originalO-acetyl groups.237 A linear glucomannan, mainly 1,4-@-linked pyranoseunits, and with twice as much mannose as D-glucose, has been isolated fromthe wood of red maple ( h e r rztbium L.).238 Another glucomannan has beenobtained from white spruce (Picea gla~ca).~~~ That from jack pine (Pinzcsbanksiana, Lamb) consists of 1,4-linked P-D-glucose and P-D-mannOSe units(proportion about 1 : 3) with D-glucose or D-gdaCtOSe forming the non-reducing end-group.m Similar galactoglucomannans are present in manyconifers 241 but non-destructive methods of isolation are needed. The poly-saccharides of the inner bark of the white spruce include starch, much pecticmaterial, and hemicelluloses similar to those of the wood.242 A pectic acid,a 4-O-methylglucuronoxylan, and a cellulose have been obtained from the227 G.J. Walker and W. J. Whelan, Biochem. J., 1960, '96, 264.228 I. M. Mackie and E. Percival, J., 1960, 2381.228 A. R. Archibald, E. L. Hirst, D. J. Manners, and J. F. Ryley, J . , 1960,230 For a recent review, see G. 0. Aspinall, Adv. Carbohydrute Chem., 1959, 14, 429.231 G. 0. Aspinall and I. M. Cairncross, J., 1960, 3877.832 K. Matsuzaki, M. Mariya, and €3. Sobue, J . Chem. SOC. Japan, Ind. Chem. Sect.,233 P. J. Garegg and B. Lindberg, Acta Chem. Scand., 1960, 14, 871.234 I. Croon and T. E. Timell, J . Amer. Chem.Soc., 1960, 82, 3416.535 D. V. Myhre and F. Smith, J . Agric. Food Chem., 1960, 8, 364.236 P. C . Das Gupta, J . Sci. Ind. Res., 1960,19, B, 148; G. G. S. Dutton and K. Hunt,237 0. E. ahrn and I. Croon, Svensk Papperstidn., 1960, 63, 601; T. E. Timell, J .288 A. J. Mian and T. E. Timell, Canad. J . Chem., 1960, 38, 1511.239 A. Tyminski and T. E. Timell, J , Amer. Chem. SOL, 1960, 82, 2823.240 C. T. Bishop and F. P. Cooper, Canad. J . Chem., 1960, 38, 793.241 J. K. Hamilton, E. V. Partlow, and N. S. Thompson, J . Amer. Chem. SOC., 1960,232 T. J. Painter and C. B. Purves, T A P P I , 1960, 48, 729.556.1960 63, 638.J . Amer. Chem. SOC., 1960, 82, 1682.Amer. Chem. SOC., 1960, 82, 5211.82, 451350 ORGANIC CHEMISTRY.inner bark of white birch (Betzda papyrifera) .243 A polysaccharide from thecompression wood of Norwegian spruce (Picea abies Karst .) is a galactan con-taining about 13% of uronic acid groups.The neutral part of the poly-saccharide is essentially linear chains of 1,4-P-~-galactose.~ Complexarabogalactans have been obtained from Larix species.245Miscellaneous.-Mild extraction methods have given three fractions, allcontaining D-glucosamine, from yeast-cell wall. One is a mannan-proteincomplex, and another is possibly a glucan-mannan-protein complex. Notmore than about 9% of the total D-glucosamine is present as Thecell walls of a pathogenic yeast, Candida albicans, contain, in addition tochitin, a highly branched glucan with lp-6 and lp-3 linkages and a highlybranched mannan with lor-2 and la-6 linkages.247 One of the two extra-cellular polysaccharides produced by Cryptococcus Zaureiztii has a mannose-containing backbone with D-xylose and D-ghcuronic acid end-groups whereasthe other contains D-glUCOSe units joined through several differentpositions.wAlthough common in hemicelluloses 4-O-methyl-~-ghcuronic acid hasbeen isolated for the first time from a bacterial source.249Variation in the composition of the gum in different nodules from theNigerian tree Combreturn Zeonense was quite marked. In one nodule theuronic acid anhydride content was 19% whereas in another it was 15y,,.250The bark gum of plums differs somewhat from the fruit gum having propor-tionately more D-mannose, L-arabinose, and hexuronic acid.251 An enzymeis present in commercial pectinase which attacks the methyl ester of pecticacid, giving a 4,5-double bond.252 The reaction is similar to the trans-elimination observed in the neutral 253 and alkaline degradation of pectin;the enzyme is therefore called “ pectin trans eliminase.” 252 Further in-vestigation of the polysaccharide from sugar-beet chips has shown that inaddition to L-arabinofuranose it contains D-galactopyranose units probablyattached to each other.254 A polysaccharide from the red alga Furcellariafastigiata is rather similar to K-carrageenin although it has a lower sulphatecontent .255The structure and immunological specificity of polysaccharides has beenreviewed.256 Type I pneumococcal capsular polysaccharide is built up fromD-galacturonic acid (60y0), D-galactose, L-fucose, and D-glucosamine (8%)243 A.J. Mian and T. E. Timell, Canad. J. Chem., 1960, 38, 1191.244 H. 0. Bouveng and H. Meier, Acta Chem. Scand., 1959, 13, 1884.245 G. A. Adams, Canad. J . Chem., 1960,38,280; H. 0. Bouveng, Acta Chem. Scand.,246 E. D. Korn and D. H. Northcote, Biochem. J., 1960, 75, 12.247 C. T, Bishop, F. Blank, and P. E. Gardner, Canad. J . Chem., 1960, 38, 869.248 M. J. Abercrombie, J. K. N. Jones, M. V. Lock, M. B. Perry, and R. J. Stoodley,249 B. A. Humphrey, Nature, 1959, 184, 1802.250 D. M. W. Anderson, E. L. Hirst, and N. J. King, Talanta, 1959, 3, 118.251 L. Hough and J. B. Pridham, Biochem. J., 1959, 73, 550.252 P. Albersheim, H. Neukom, and €3. Deuel, Helv. Chim. Acta, 1960, 43, 1422.253 P. Albersheim, H. Neukom, and H. Deuel, Arch. Biochem. Biophys., 1960,254 L. Hough and D. B. Powell, J., 1960, 16.253 T. J. Painter, Canad. J . Chem., 1960, 38, 112.356 M. Neidelberger, Fortschr. Chem. org. Naturstofle, 1960, 28, 603.1959, 13, 1869, 1877.Canad. J . Chem., 1960, 38, 1617.90, 46HONEYMAN : CARBOHYDRATES. 351but another nitrogen-containing unit must also be present .257 Aspergillusparasiticus produces a D-galactosamine analogue of chitin.%Summaries have been published of the papers presented at a symposiumon the biochemistry of mucopolysaccharides of connective tissue.259ECTEOLA, made by treating cellulose with epichlorohydrin and triethanol-amine, has been used for separating hyaluronic acid, chondroitin sulphuricacid, and heparin,260 and for fractionating heparin.261 Dermatan sulphate(@-heparin, chondroitin sulphate B) contains L-iduronic acid.2G2The cell-walls of some micro-organisms contain a considerable amountof a phosphoric ester polymer known as a teichoic acid.263 About 60% ofthe dry weight of Bacillus subtdis is a ribitol teichoic acid containing D-alanine, D-glucose, ribitol, and phosphate. The alanine is joined to hydroxylin the polymer by unusually stable ester links and the rest of the molecule isas shown below.264OH H H HI I l l1 1 1,O- PO-0- H2C - C- C-C- CH2 - -OH8J. H.M. F. ANSELL.R. K. CALLOWN. B. CHAPMAN.J. ELKS.F. G. GUNSTONE.J. HONEYMAN.G. LOWE.A4. M. MICHELSON.&4. R. PINDER.Y. POCKER.J. H. RIDD.J. SAXTON.G. T. STEVENS.J. M. TEDDER.257 E. E. B. Smith, B. Galloway, and G. T. Mills, Biochern. J., 1960, 76, 3 5 ~ .258 J. J. Distler and S. Roseman, J . BioE. Chem., 1960, 235, 2538.259 Symp. Biochem. Mucopolysaccharides of Connective Tissue, Biochem. J., 1960,260 N. R. Ringertz and P. Reichard, Acta Chem. Scand., 1960, 14, 303.26L J. P. Green, Nature, 1960, 186, 472.262 I?. J. Stoffyn and R. W. Jeanloz, J . Bid. Chem., 1960, 235, 2507.26' J. J. Armstrong, J. Baddiley, and J. G. Buchanan, Biochem. J . , 1960, 76, 610.75, 1P.J. Baddiley, Proc. Chem. SOC., 1959, 177

ISSN:0365-6217    

DOI:10.1039/AR9605700165

出版商:RSC    

年代:1960

数据来源: RSC

摘要:

BIOLOGICAL CHEMISTRY1. INTRODUCTIONIT is now clearly established that deoxyribonucleic acid (DNA) is the carrierof genetic information in the cell and that ribonucleic acid (RNA) is, amongstother things, intimately concerned with the biosynthesis of proteins. Ittherefore comes as no surprise to find that the number of investigations onthese biological materials which are being carried out in numerous labor-atories over the world is very great; in particular the nucleic acids, morethan any other compounds, carry with them the glittering prospect of anexplanation of the ultimate mysteries of living matter.This year’s Report, therefore, begins with a discussion of the elegantwork leading to the enzymic synthesis of both RNA and DNA in cell-freesystems; the equally important investigations, at the moment only in theembryonic state, dealing with the mechanisms by which the synthesis ofthese compounds is controlled in the living cell are also considered.The second and third Sections are devoted to topics not previouslydiscussed in Annual Reports; they are also closely linked.Developments inneurochemistry during the past decade have been considerable and manyhave been due to the thoughtful application of new biochemical techniquesto appropriate problems, although, as indicated in the second Section, 30divisions of the subject based on many fundamental disciplines have beenmade. The topics selected for discussion-neural maintenance and excit-ation-ramify widely into almost all these divisions.The movement ofions in nerve cells is intimately concerned with neural activity and it is thisaspect of “ active transport ” which is emphasised in the third Section.Space did not allow a detailed consideration of the active transport oforganic materials. In the field of ion transport it is probably correct to saythat most progress has so far been made by the physiologist, and it is onlycomparatively recently that biochemically meaningful questions could beposed. The possibilities of development in this field are fascinating.The terminal steps in cellular respiration are concerned with the move-ment of electrons from a substrate to oxygen against a potential gradient,with the accumulation of available energy in the form of adenosine tri-phosphate, the energy currency of the cell.This process takes place in themitochondria of the cell and the final Section of this Report concerns in-vestigations which have been carried out to relate the structure of the mito-chondrion to its function, to d e h e more clearly the electron carriers involved,and to reveal the mechanism involved in the formation of ATP (oxidativephosphorylation) .T. W. G.2. BIOSYNTHESIS OF NUCLEIC ACIDSAbbreviations Employed.-In conformity with common usage the ribo-nucleoside mono-, di-, and tri-phosphates of adenosine are denoted byAMP, ADP, and ATP, of guanine by GMP, GDP, and GTP, of uracil bDAVIDSON : BIOSYNTHESIS OF NUCLElC ACIDS. 353UMP, UDP, and UTP, of cytosine by CMP, CDP, and CTP, and of hydroxy-methylcytosine by HMCMP, HMCDP, and HMCTP.The prefix d is usedto denote the corresponding deoxyribonucleoside derivatives. PP standsfor inorganic pyrophosphate and Pi for inorganic orthophosphate.THE chemistry of the nucleic acids has been surveyed recently in theseReports and the biosynthesis of the purine and pyrimidine nucleotides hasbeen covered in several reviews2 The report that now follows is concernedessentially with the biosynthesis of polynucleotides from mononucleotideunits. The subject has been reviewed by several author^.^Deoxyribonucleic Acid (DNA) .-Our present knowledge of the mechanismof the biosynthesis of DNA originates from the work of Kornberg and hiscolleagues who showed that cell-free extracts made from exponentiallygrowing cultures of Escherichia coli contained an enzyme (polymerase)which could bring about the synthesis of DNA in the presence of the deoxy-nucleoside triphosphates of the four predominant bases adenine, guanine,cytosine, and thymine, Mg++, and DNA primer, according to the followingreaction : 596ndATP +ndGTP + +DNA L DNA-ndCTP +nTTP+ 4nPPThe reaction is accompanied by the release of inorganic pyrophosphateequimolar with the amount of nucleotide incorporated and is inhibited byhigh concentrations of pyrophosphate.Pyrophosphorolysis can be demon-strated by carrying out the reaction in presence of 32P-pyrophosphate whichexchanges with the terminal pyrophosphate group of the deoxyribonucleosidetriphosphates6 The presence of DNA is essential for the reaction to occur.The enzyme catalysing the reaction has been purified more than 2000-fold and has been used to demonstrate net synthesis of DNA as measuredby the incorporation of isotopically labelled substrates, by ultravioletabsorption or deoxypentose estimations in the acid-precipitable products ofthe reaction, or by the increase in the viscosity of the reaction mixture.’D.M. Brown, Ann. Reports, 1958, 55, 330.J. Baddiley and J. G. Buchanan, Ann. Reports, 1957, 64, 329; J. M. Buchananin ‘‘ The Nucleic Acids ” (eds. E. Chargaff and J. N. Davidson), Academic Press, NewYork, 1960, Vol. 111, p. 304; G. W. Crosbie, op. cit., p. 343.H. G. Khorana, op. cit., p. 105; J. N. Davidson, “ The Biochemistry of the NucleicAcids,” Methuen, London, 1960; A.M. MiyFlson, Actu Biochim. Polon., 1959, 6, 335;H. K. King, Science Progr., 1960, 48, 284; Enzymes of Polynucleotide Metabolism,”Ann. New York Acad. Sci., 1959, 81, Art. 3, pp. 511-804.A. Kornberg, Science, 1960, 131, 1503; Harvey Lectures, 1959, 53, 83.6 I. R. Lehman, M. J. Bessman, E. S. Simms, and A. Kornberg, J . Biol. Chew.,1958, 233, 163.M. J. Bessman, I. R. Lehman, E. S. Simms, and A. Kornberg, J . Biol. Chem.,1958, 233, 171.7 H. K. Schachman, I. R. Lehman, M. J. Bessman, J. Adler, E. S. Simms, and A.Kornberg, Fed. Pvoc., 1958, 17, 304.REP.-VOL. LVII 354 BIOLOGICAL CHEMISTRY.The increase in DNA is 10-2O-fold, indicating that 90-95% of the DNAisolated from the reaction mixture has its origin in the deoxyribonucleosidetriphosphate substrates.The enzymically synthesised DNA has essentially the same physicalproperties as DNA isolated from natural sources in terms of sedimentationcoefficient and of the results of measurement of reduced viscosity whichindicate a molecular weight of 4 - 6 million.It appears to be organised asrelatively stiff macromolecules which, like those of calf thymus DNA,collapse in 15 min. at 100” with a pronounced reduction in intrinsic viscositybut only a slight lowering of sedimentation coefficient. Digestion withpancreatic deoxyribonuclease produces an increase in ultraviolet absorptionto an extent identical with that observed with thymus DNA.’The deoxyribonucleotides incorporated into the enzymically synthesisedDNA are joined by the 3’,5’-phosphodiester linkage which is characteristicof DNA isolated from cell nuclei.6 If, in the synthetic reaction, the fourtriphosphates are replaced by a single radioactive deoxyribonucleosidetriphosphate, a “ limited reaction ” occurs in which only one or a very fewmolecules of the added deoxyribonucleotide react at the end of the DNAprimer chain, becoming attached by 3‘,5’-phosphodiester linkages8 Hydro-lysis of this material by snake-venom phosphodiesterase causes sequentialliberation of deoxyribonucleotides from the deoxyribonucleoside end of thechain and liberates nearly all the radioactivity as acid-soluble deoxyribo-nucleotides a t a time when less than 3% of the total deoxyribonucleotideshave been released.This limited reaction appears to represent the repairof the shorter strand of a double helix in which the strands are of unequallength.4 Further synthesis cannot occur in the absence of the other threetriphosphates.On the basis of this and other evidence it has been concluded that themechanism of the synthetic reaction involves a nucleophilic attack on thepyrophosphate-activated deoxyribonucleoside 5’-phosphate by the 3’-hydroxyl group a t the growing end of a polydeoxyribonucleotide chain(Formula I).Inorganic pyrophosphate is liberated and the chain is length-ened by one unit.4A similar polymerase system requiring the deoxyribonucleoside tri-phosphates, primer DNA, and Mg++ occurs in cell-free extracts of Ehrlichascites carcinoma cells,g regenerating rat liver,l09l1 calf thymus,12J3 HeLacells,13 mouse leukaemic cells,14 and Novikoff hepatoma.15 It is mostJ.Adler, I. R. Lehman, M. J. Bessman, E. S. Simms, and A. Kornberg, Proc.Nut. Acad. Sci. U.S.A., 1958, 44, 641.9 J. N. Davidson, R. M. S. Smellie, H. M. Keir, and A. H. McArdle, Nature, 1958,182, 589; R. M. S. Smellie, H. M. Keir, and J. N. Davidson, Biochim. Biofihys. Acta,1959, 35, 389; R. M. S. Smellie, E. D. Gray, H. M. Keir, J. Richards, D. Bell, andJ. N. Davidson, ibid., 1960, 37, 243.lo F. J, Bollum and V. R. Potter, J . Bid. Chem., 1958, 233, 478; R. Mantsavinosand E. S. Canellakis, ibid,, 1959, 234, 638.11 F. J. Bollum and V. R. Potter, Cancer Res., 1959, 19, 561.l2 F. J. Bollum, J . Bid. Chem., 1960, 235, 2399.13 C. G. Harford and A.Kornberg, Fed. Proc., 1958, 17, 515.l4 R. Mantsavinos and E. S. Canellakis, Cancer Res., 1959, 19, 1239.N. B. Furlong and A. C. Griffin, Fed. Proc., 1960, 19, 306; N. B. Furlong, Arch.Biocheun. Bioplays., 1960, 87, 154DAVIDSON BIOSYNTHESIS OF NUCLEIC ACIDS. 355abundant in extracts of rapidly proliferating cells9 and has been purifiedfrom extracts of calf thymus l2 and Ehrlich ascites cells.16P O=P-0I0ICkYase O HIO=P-cT PolynucleotideI F’HQ HO-P-O-P-O-P-O- 9\ L ? I 1 6- 6- 0-(1)ribonucleotide. TheSince the product of polymerase action is a con-ventional double helix conforming to the Watson-Crick model it is not surprising to find that specificreplacement of certain bases by analogues can bemade provided that the correct hydrogen bondingrelations are maintained in the “ fraudulent ” DNA’sso f0rmed.l’ Thus uracil and 5-bromouracil (sup-plied as the deoxyribonucleoside triphosphates) canreplace thymine since they possess the 6-keto-groupand the 1-hydrogen atom necessary for hydrogenbonding with the corresponding 6-amino-group andl-nitrogen atom of adenine.5-Methyl- and Fi-bromo-cytosine can replace cytosine, and hypoxanthine canreplace guanine. The absence of uracil from ordinaryDNA may be explained by the fact that extracts ofEsclz. coli contain no kinases for the phosphorylationof deoxyuridylate to the triphosphate although theycan phosphorylate 5-bromodeo~yuridylate.~~Hurwitz18 has purified from extracts of Esch.coli an enzyme system which brings about the in-corporation dATP, dGTP, TTP, and CTP into a poly-deoxynucleotide material in which the ribonucleotideCMP occurs in a position adjacent to a deoxy-resultant mixed polpucleotide is rendered at leastpartly acid-soluble by alkali and by bothdeoxyribonuclease and ribonuclease.Partial degradation yields a dinucleotide composed of a ribonucleotide anda deoxyribonucleotide and the 3’,5’-diester linkage is confirmed by thetransfer of labelled 5’-phosphate from the added ribonucleotide to the 3’-position on the adjacent deoxyribonucleotide in the final polynucleotide chain.Determination of the chemical composition of the DNA synthesisedenzymically by the Kornberg system in the presence of a variety of DNAprimers shows the close correspondence of adenine and thymine residues andof guanine and cytosine residues required by the Watson-Crick structure.lgMoreover the ratio of the number of adenine-thymine pairs to the numberof guanine-cytosine pairs reflects the ratio present in the primer ; such ratiosvary from 0.5 for the DNA of M .phlei to 40 or more for the copolymer ofdeoxyadenylate and thymidylate (see below). This close correspondencebetween product and primer holds even with widely differing molarconcentrations of the four substrates and with net increases in DNA varyingfrom 1 to 1000%.19l6 E. D. Gray, S. M. Weissman, J. Richards, D. Bell, H. M. Keir, R. M. S. Smellie,l7 M. J. Bessman, I. R. Lehman, J. Adler, S. B. Zimmerman, E. S. Simms, andla J. Hunvitz, J. Biol.Chem., 1959, 234, 2351.I. R. Lehman, S. B. Zimmerman, J. Adler, M. J. Bessman, E. S. Simms, andand J. N. Davidson, Biochim. Biophys. Acta, 1960, 45, 111.A. Kornberg, PYOC. Nat. Acad. Sci. U.S.A., 1958, 44, 633.A. Kornberg, Proc. Nut. Acad. Sci. U.S.A., 1958, 44, 1191356 BIOLOGICAL CHEMISTRY.The polymerase enzyme is therefore unique in taking directions from atemplate and in faithfully reproducing the pattern of the primer.4 Whileextensive destruction of the primer with pancreatic deoxyribonucleasedestroys the priming capacity of thymus DNA, heating to 100" for 10 min.with resultant collapse of the macromolecular structure, as shown by a 30%hyperchromicity and a loss of viscosity, produces a primer which is twice aseffective in supporting DNA synthesis as the unheated material and theproduct synthesised is highly viscous.2o Since heating results in the form-ation from the double-stranded helix of two single-stranded polynucleotidechains 21 on each of which a complementary chain is presumably constructed,it is not surprising to find that the single stranded non-viscous DNA22isolated from the small phage +X 174 is an excellent primer for the Esch.coli p0lymerase.2~Treatment of primer DNA with minute amounts of deoxyribonuclease,while failing to cause extensive degradation, results in a two- or three-foldincrease in priming ability.6s20 It may well be that the activity of thenucleases which still contaminate even purified polymerase preparations,causes sufficient degradation of DNA for it to be possible to use ordinarydouble-stranded DNA as primer in partly purified systems.This view receives support from Bollum's observation 23 that whereascalf-thymus polymerase l2 cannot use " native " DNA as primer for DNAsynthesis, either the single-stranded +X 174 DNA, or a deoxyribopoly-nucleotide formed from native DNA by any physical or chemical treatmentwhich leads to denaturation of the double-stranded molecule, is effective.Thus treatment with pancreatic deoxyribonuclease or heating at 99" for10 minutes followed by rapid cooling, so as to cause denaturation by breakageof hydrogen bonds with single chain formation, is effective, whereas sonicdegradation producing molecular-weight reduction by double-chain scis-and digestion by micrococcal nuclease or snake-venom diesterase, areineffective unless the product is denatured after digestion with the formationof single-stranded regions which are the actual priming sites. Unlike thepolymerase from Esck.coli the thymus polymerase can utilise as primer theacid-soluble limit deoxyribopolynucleotides in a pancreatic digest of DNAor chemically synthesised thymidylate polymers containing 3-7 thymi-dylate residuesz5When the Esck. coli polymerase is incubated with dATP and TTP in theabsence of the other two triphosphates and of DNA primer an A-T polymeris formed after a lag period of about 4 hours.20s26 It has the physicalproperties of natural DNA with adenine and thymine in alternating sequence.20 I. R. Lehman, Ann, New York Acad.Scz., 1959, 81, 745.21 P. Doty, J. Marmur, J. Eigner, and C. Schildkraut, R o c . Nut. Acad. Sci. U.S.A.,22 R. L. Sinsheimer, J. Mol. Biol., 1959, 1, 43.23 F. J. Bollum, J . Biol. Chem., 1959, 234, 2733; F6d. Proc., 1960, 19, 305.24 P. Doty, B. B. McGill, and S. A. Rice, PYOG. Nut. Acad. Sci. U.S.A., 1958, 44,432; F. J . Bollum, in " The Cell Nucleus," ed. J . S. Mitchell, Butterworths, London,1960, p. 60.25 F. J. Bollum, J . Biol. Chem., 1960, 235, PC18.26 H. K. Schachman, C. M. Radding, J. Adler, I. R. Lehman, and A. Kornberg,J . Biol. Chem., 1960, 235, 3242.1960, 46, 461DAVIDSON : BIOSYNTHESIS OF NUCLEIC ACIDS. 357When this polymer is used as primer, synthesis of A-T polymer startsimmediately and the product contains no trace of guanine or cytosine eventhough all four triphosphates are present in the incubation mixture.Of the nucleotide sequences in enzymically synthesised DNA little isknown, but it has been shown by degradation with DNA primer samplesfrom six natural sources that all sixteen possible dinucleotide sequences arefound in each case, that the pattern of relative frequencies of the sequencesis unique in each case and is not predicted from the base composition of theDNA, and that enzymic replication involves base pairing of adenine tothymine and of guanine to cytosine in two strands of opposite direction aspredicted by the Watson-Crick m0de1.~~~'The kinases which bring about phosphorylation of deoxyribonucleosidesor their monophosphates have been intensively studied in soluble extractsof Esch.coli,s Ehrlich ascites tumour cells28 and regenerating ratliver,10~11,29-31 and the reaction may be used on a preparative scale for thesynthesis of the triphosphates.59 28 The enzymes responsible for the phos-phorylation of thymidine and TMP to TTP are of special interest, foralthough their activity is very low in extracts of normal liver, it is pro-nounced in extracts of liver regenerating after partial hepatectomy. In thisrespect the thymine nucleotide kinase system differs from the kinases in-volved in the phosphorylation of dAMP, dGMP, and dCMP which are ofcomparable activity in normal and regenerating 1iver.llP 31 During theregeneration of liver the kinases for the phosphorylation of thymidine,TMP, and TTP appear in that order, reach maximum activity at the timeof maximum DNA synthesis, and then d e ~ l i n e .~ ~ , ~ ~ A similar sequentialappearance of kinases is found in cultures of the L strain of fibroblastinoculated into fresh m e d i ~ r n . ~ . ~ ~The appearance of new enzymes involved in polynucleotide metabolismis well illustrated in the case of cells of Esch. coli infected with bacteriophageT2 whose DNA contains, in place of cytasine, the base hydroxymethyl-cytosine (HMC) to some residues of which glucose is Within3 minutes of infection the new enzyme, deoxycytidine hydroxymethylase,appears and catalyses the conversion of dCMP into dHMCMP.33 Threeother enzymes also appear which are undetectable in extracts of uninfectedEsch. coli or in cells infected with phage T5 which contains cytosine and not27 J.Josse and A. Kornberg, Fed. Proc., 1960, 19, 305.28 H. M. Keir and R. M. S. Smellie, Biochim. Biophys. Actu, 1959, 35, 406.2s L. I. Hecht, V. R. Potter, and E. Herbert, Biochim. Biophys. Actu, 1954, 15,134; E. S. Canellakis, J. J. Jaffe, R. Mantsavinos, and J. S. Krakow, J . Bid. Chem.,1959, 234, 2096; E. S. Canellakis and R. Mantsavinos, Biochim. Biophys. Actu, 1958,27, 644; H. H. Hiatt and T. B. Bojarski, Biochim. Biophys. Res. Comm., 1960, 2, 35.S. M. Weissman, J. Paul, R. Y. Thomson, R. M. S. Smellie, and J. N. Davidson,Biochem. J., 1960, 76, 1 ~ .31 S. M. Weissman, R. M. S. Smellie, and J. Paul, Biochim. Biophys. Acta, 1960, 45,101.32 R. L. Sinsheimer, Science, 1954, 121, 561; Proc.Nut. Acad. Sci. U.S.A., 1956,42, 502; E. Volkin, J . Amer. Chem. Soc., 1954, 76, 5892; M. A. Jesaitis, J . Ex?. Med.,1957, 106, 233; Fed. Proc., 1958, 17, 250.33 J. G. Flaks and S. S. Cohen, J . Bid. Chem., 1959, 234, 1501; J. G. Flaks, J.Lichtenstein, and S. S. Cohen, ibid., p. 1507; S. B. Zimmerman, S. R. Kornberg, J.Josse, and A. Kornberg, Fed. Proc., 1959, 18, 359; K. Ebisuzaki, E. A. Figueiredo, andS. Schlesinger, ibid., p. 219358 BIOLOGICAL CHEMISTRY.HMC. They are (a) a kinase which phosphorylates dHMCMP to the tri-p h o ~ p h a t e , ~ . ~ ~ (b) a pyrophosphatase which removes the terminal pyro-phosphate group specifically from dCTP and so ensures the absence ofdeoxycytidylate from T2 and (c) a glucosylase which transfersglucose from uridine diphosphate glucose to the hydroxyl groups in certainof the residues of HMC in the DNA after it has been formed.= Since theglucose contents of the DNA’s of phages T2, T4, and T6 are quite different 32and are genetically determined, it is to be concluded that three differentglucosylases operate in the biosynthesis of these three phage DNA’s3’The level of polymerase also increases about 12-fold after T2 infection,34and the kinases responsible for phosphorylating the deoxyribonucleosides ofthymine and guanine (but not of adenine or cytosine) increase 2 0 4 0 -The rise in dGMP kinase may represent the production of a newenzyme rather than an increased production of host enzyme since the kinaseformed after infection has properties differing from those of the hostenzyme.39 Infection with T5 phage involves an increase in the kinasesfor TMP, dGMP, and dCMP, but not for dAMP.Mys Infection with phage T2or T5 also causes the rapid appearance of the enzyme, thymine synthetase,which converts deoxyuridine monophosphate into TMP.40While the kinase systems for phosphorylating thymine deoxyribo-nucleotides clearly occupy a key position in the control of DNA bio-as also does the system involved in the conversion ofuracil into thymine n~cleotides,~O-*~ several other factors also play an im-portant part: (a) the control of the biosynthesis of purine and pyrimidinederivatives in general by feedback rnechanism~,4~*~~,~ (b) the eliminationfrom rapidly growing tissues of the enzymes responsible for nucleotidecatab~lisrn,~~, (c) the conversion of ribonucleotides into deoxyribonucleo-tide.^,^^-^^ which appears to take place at the nucleoside diphosphate34 A.Kornberg, S. B. Zimmerman, S. R. Kornberg, and J. Josse, Proc. Nat. Acad.Sci. U.S.A., 1959, 45, 772.85 R. Somerville and G. R. Greenberg, Fed. Proc.. 1959, 18, 327; R. Somerville,K. Ebisuzaki, and G. R. Greenberg, Proc. Nat. Acad. Sci. U.S.A., 1959, 45, 1240.J. F. Koerner, M. S. Smith, and J. M. Buchanan, J . Amer. Chem. Soc., 1959, 81,2594; J. F. Koerner, M. S. Smith, and J. M. Buchanan, J . Bid. Chem., 1960, 235, 2691.37 L. M. Kozloff, Ann. Rev. Biochem., 1960, 29, 475.38 M. J. Bessman, J . Bid. Chem., 1959, 234, 2735.3O M. J. Bessman and M. J.Van Bibber, Biochem. Biophys. Res. Comm., 1959, 1,4O J. G. Flaks and S. S. Cohen, J . Bid. Chem., 1959, 234, 2981; H. D. Barner and4 1 V. R. Potter, Univ. Michigan Med. Bull., 1957, 23, 401.43 V. R. Potter, Fed. PYOC., 1958, 17, 691.43 M. Friedkin, in “ Kinetics of Cellular Proliferation,” ed. F. Stohlman, Grune &Stratton, New York, 1959, p. 97.44 B. Magasanik, in “ The Regulation of Cell Metabolism,” ed. G. E. W. Wolsten-holme and C. M. O’Connor, Churchill, London, 1959, p. 306; J. B. Wyngaarden andD. M. Ashton, J . Biol. Chem.. 1960, 234, 1492.45 G. de Lamirande, C. Allard, and A. Cantero, Cancer Res., 1958, 18, 952; V. R.Potter, in “ Kinetics of Cellular Proliferation,” ed. F. Stohlman, Grune & Stratton,New York, 1959, p. 104.41, 558.No.2, 101.S. S. Cohen, ibid., p. 2957.46 P. Reichard and L. Rutberg, Biochim. Biofhys. Acta, 1960, 37, 554.47 P. Reichard, 2. N. Canellakis, and E. S. Canellakis, Biochirn. Biophys. Acta, 1960,4R P. Reichard, Biochim. Biophys. Ada, 1960, 41, 368.49 N. R. Norris and G. A. Fischer, Biochim. Biophys. Ada, 1960, 42, 183DAVIDSON : BIOSYNTHESIS OF NUCLEIC ACIDS. 359stage47sa and in the case of the cytosine nucleotides, at least, to be in-hibited by deoxyribonucleoside tripho~phates,~~~ 49 and (d) the presence oftissue factors 16,m in non-proliferating cells which interfere with the poly-merase and the kinases for the thymine deoxyribonucleotides but not withthose of adenine, guanine, and cytosine.The importantwork of Ochoa and his colleagues on the enzyme polynucleotide phos-phorylase and the biosynthetic ribopolynucleotides which are producedunder its influence has already been discussed in these Reports1 and inother review^.^^^^^^^ The enzyme catalyses the reaction by which ribo-nucleoside diphosphates are condensed to give a ribopolynucleotide with theelimination of inorganic orthophosphate in the presence of Mg++, thus :n Nucleoside-P-P z+= (nucleoside-P), + nP1Ribonucleic Acid, (RNA) .--PoZyrtucZeofide Phosphorylase.and also the exchange reactionNucleoside-P-P + szPi Nucleo~ide-P-~~P + Piwhere Pi = inorganic phosphate.The enzyme appears to be essentially bacterial in occurrence althoughits presence has been reported in yeasts and plants and in several mammaliantissues such as liver nuclei,% Ascaris Zumbticoides,5q rat epitheli~ma,~~ andhuman sperm and urine.56 Only a few important new developments will bediscussed here.Partly purified enzyme preparations from Axotobacter vinelaadii causeimmediate formation of polymer from ribonucleoside diphosphates inpresence of Mg++.With more fully purified preparations polymerisationoccurs only after a lag period which can be overcome by addition of poly-nucleotide or of simple oligonucleotides 52j57958 of the type pApApA, ApApA,ApU, or UpApU.* The essential features of the primer are that it shouldbe a dinucleotide or larger and that it should contain a terminal nucleosideresidue with a free C-3’ hydroxyl group with which a new phosphodiesterbond can be formed thuspApA + nUDP ____) pApAUpU .. . pUpU + nPi50 S. M. Weissman, E. D. Gray, R. Y . Thomson, R. M. S. Smellie, and J. N. David-son, Biochem. J., 1960, 76, 2 6 ~ .51 S. Ochoa, Onzihme Conseil de Chimie, Institut de Chimie Solvay, “ Les Nucleo-proteines,” R. Stoops, Brussels, 1959, p. 241 ; 7th Internat. Congr. Microbiol. Stock-holm, 1958; ‘* Recent Progress in Microbiology,” ed. G. Tunevall, 1959, p. 122; Ann.New York Acad. Sci., 1959, 81, 690; Angew. Chem., 1960, 72, 225.52 M. F. Singer, L. A. Heppel, R. J. Hilmoe, S. Ochoa, and S. Mii, Proc. 3rd Canad.Cancer Res. Confer., 1959, Vol. 111, p. 41.53 R. J. Hilmoe and L. A. Heppel, J . Amer. Chem. SOC., 1957, 79, 4810.54 N. Entner and C. Gonzalez, Biochem. Biophys. Res. Cornm., 1959, 1, 333.55 K.Yagi, T. Oyowa, and H. Konogi, Nature, 1959, 184, 1939.56 A. A. Hakim, Enzymologia, 1959, 21, 81.67 R. J. Hilmoe, Ann. New York Acad. Sci., 1959, 81, 660; M. F. Singer, L. A.Heppel, and R. J. Hilmoe, J . B i d . Chem., 1960, 235, 738.58 L. A. Heppel, M. F. Singer, and R. J. Hilmoe, Ann. New York Acad. Sci., 1959,81, 635.* In this commonly used form of notation a phosphate group is denoted by p;when i t is placed to the right of the nucleoside symbol (A, G, C, or U) the phosphate isesterified at C-3’ of the ribose moiety; when it is placed to left of the nucleoside symbol,the phosphate is esterified at C-6’ of the ribose moiety360 BIOLOGICAL CHEMISTRY.The first bond formed is a diester bridge between the 5’-phosphate of aUMP residue and the free terminal 3‘-hydroxyl group of pApA, and thechain is extended by similar condensations, the primer being incorporatedinto the product.The mechanism of the reaction is illustrated in (11) inwhich the terminal unit of the existing polynucleotide (or oligonucleotide)chain is represented by the nucleotide residue attached to R.L7 PI + -0-6.10 + IOH OH OH OH(11)If this mechanism is correct, oligonucleotides with a terminal 3’-hydroxylesterified with phosphate should not act as primers. Nevertheless, sucholigonucleotides as ApApUp can abolish the lag period without themselvesbeing incorporated into the polymer.52Polynucleotides themselves can abolish the lag period but in a moreselective way. Thus polyA will prime its own synthesis but not that ofpolyU or polyAGUC, while polyAGUC and polyAU will both prime thesynthesis of polyA and of polyU.s1*6aIt was originally reported that when GDP is used as substrate for poly-nucleotide phosphorylase, polymer formation is either very slow or un-detectable although it does occur in presence of such primers as pApA orA P A ~ U , ~ ~ but more recent work with enzyme preparations from Esch.coliand Axotobacter agilis has shown that a reaction takes place with GDP aloneprovided that favourable concentrations of Mg++ and inorganic phosphateare employed.6oThe reversal of the polymerisation, namely, phosphorolysis, in whichthe polynucleotide is incubated with the enzyme in presence of an excess ofinorganic phosphate to yield the nucleoside diphosphates by stepwise re-moval of mononucleotide units has also been studied.62*s*s61 The bio-synthetic polymers are readily phosphorolysed and so are oligonucleotideswhich act as primers, but, as might be expected, dinucleotides and dinucleo-side monophosphates are not.Tobacco mosaic virus RNA and highlypolymerised yeast RNA are phosphorolysed readily, but yeast RNA treatedwith alkali is phosphorolysed slowly. The formation of multistranded chains,as between polyA and polyU, results in a slow rate of phosphoroly~is.~~~~*69 M. F. Singer, R. J. Hilmoe, and L. A. Heppel, J . Bid. Chem., 1960, 235, 761.6o M. F. Singer, R. J. Hilmoe, and M. Grunberg-Manago, J . Biol. Chem., 1960, 235,M. Grunberg-Manago, J . Mol. B i d , 1969, 1, 240; M.F. Singer, S. Luborsky,2705.R. A. Morrison, and G. L. Cantoni, Biochim. Biophys. Acta, 1960, 88, 668DAVIDSON : BIOSYNTHESIS OF NUCLEIC ACIDS. 361The soluble RNA of the cell cytoplasm is peculiar in being incompletelyphosphorolysed, 70-80% being left unchanged.61 The phosphorolysisappears to affect mainly the terminal groups.62It has been considered that polynucleotide phosphorylase from Axoto-bacter vinelandii and Esclz. coli also catalyses the exchange reaction betweennucleoside diphosphates and inorganic phosphate, but in yeast the enzymeresponsible for this reaction can be separated from polynucleotide phos-ph0rylase.~3The addition of alimited number of nucleotide units to the end of an existing ribopolynucleo-tide chain cannot be regarded as polynucleotide synthesis but is neverthelessan allied reaction of considerable importance about which much is nowknown.Heidelberger and his associatesM365 showed in 1956 that 32P-adenosine-5’ monophosphate in the presence of a phosphorylating systemwas incorporated into the RNA of rat liver cytoplasm. Hydrolysis withsnake-venom diesterase yielded 32P-5’-AMP, and hydrolysis with alkaliyielded 32P-cytidine-2’ and -3’ monophosphate. This suggested a prefer-ential linkage of AMP to CMP in the RNA. Similar observations on variousbiological materials by a number of ~ o r k e r s , ~ ~ - ’ ~ together with the findingthat most of the incorporated adenine is released as the nucleoside on alkalinehydrolysis, indicated that the AMP had been added in the terminal positionon an RNA chain.The significance of some of these observations has beenelucidated by Zamecnik, Hoagland, and their c ~ l l e a g u e s , ~ ~ - ~ ~ working withthe soluble or transfer RNA (sRNA) of rat-liver cytoplasm which differsfrom the RNA of the ribosomes or microsomes in its peculiar capacity toact as acceptor in terminal-group additions. Such additions are an oblig-atory prelude to amino-acid attachment in the process of protein bio-T h e terminal addition of nucleotide u n i t s to RNA.6e E. S. Canellakis, Biochem. J., 1960, 77, 1 4 ~ .63 M. Grunberg-Manago, Biochem. J., 1960, 7’7, 1 3 ~ .64 C. Heidelberger, E. Harbers, K. C . Leibman, Y . Takagi, and V. R. Potter, Biochim.66 E. Harbers and C. Heidelberger, Biochim.Biophys. Acta, 1959, 35, 381.66 D. A. Goldthwait, Biochim. Biophys. Acta, 1958, 30, 643.67 (a) D. A. Goldthwait, J . Bid. Chem., 1959, 234, 3251; A. R. P. Paterson andG. A. Lepage, Cancer Res., 1957, 17, 409; (6) E. S. Canellakis, Ann. New Yovk Acad.Sci., 1959, 81, 675.68 E. S. Canellakis, Biochim. Biophys. Acta, 1957, 23, 217.69 M. Edmonds and R. Abrams, Biochim. Biophys. Acta, 1957,26, 226.70 E. Herbert, J . Biol. Chem., 1958, 231, 975.71 J. Preiss and P. Berg, Fed. Proc., 1960, 19, 317.72 J. Hurwitz, A. Bresler, and R. Diringer, Biochem. Bioplijv. Res. Comm., 1960,7a J. S. Krakow and H. 0. Kammen, Fed. Proc., 1960, 19, 307. ’* M. Edmonds and R. Abrams, Fed. Proc., 1960,19, 317.75 S. B. Weiss and C . Gladstone, J . Amer. Chem.Soc., 1969, 81, 4118.E. Herbert, Ann. New York Acad. Sci., 1959, 81, 679.77 R. H. Burdon and R. M. S. Smellie, Biochem. J., 1960, 76, ZP.7~ R. H. Burdon and R. M. S. Smellie, Biochim. Biophys. Acta, 1961, 47, 93.79 M. Hoagland, in “ The Nucleic Acids,” eds. E. Chargaff and J. N. Davidson,L. I. Hecht, P. C. Zamecnik, M. L. Stephenson, and J. F. Scott, J . Biol. Chem.,L. I . Hecht, M. L. Stephenson, and P. C. Zamecnik, Proc. Nut. Acad. Sci. U.S.A.,Biophys. Acta, 1956, 20, 445.3, 15.Academic Ress, New York, 1960, Vol. 111, p. 349.1958, 233, 954.1959, 45, 505.82 P. C. Zamecnik, T h e Hwwey Lectures, 1960, 54, 256362 BIOLOGICAL CHEMISTRY.s y n t h e s i ~ . ~ ~ ~ ~ ~ The sRNA’s from mammalian tissues, yeast, and bacteria allbehave in the same manner.The precursors of the terminally added nucleotide units are the ribo-nucleoside triphosphates, and their attachment involves a reversible pyro-phosphate splitting.Pyrophosphate inhibits the attachment and accumu-lates during the process.76The base sequence in sRNA is unknown, but ‘ I preincubation ” followedby precipitation at pH 5 gives an acceptor material whose end groups maybe represented as X and Y (see 111). Two CMP moieties are first attachedX Y C X Y CX Y C C X Y C CX Y C C A X Y C C Asequentially to the 3’-hydroxyl group of the ribose in the terminal nucleo-tide Y. The new terminal CMP now accepts an AMP residue by a similarpyrophosphoryl cleavage of ATP. The final sequence at the end of thepolynucleotide chain is therefore - - * pXpYpCpCpA.676p 763799*2 The evidence€or this may be summarised as follows: (a) incubation of sRNA with 14C-CTP causes incorporation of 14C into the RNA which on alkaline hydrolysisyields one half of its 14C as cytidine and one half as cytidine 2’(or %)-mono-phosphate; (b) when ATP is also present in the incubation mixture all the14C is recovered as cytidine 2’(or 3’)-monophosphate ; (c) incubation with14C-ATP results in terminal attachment of 14C-AMP which is released byalkali as 14C-adenosine ; ( d ) the incorporation is inhibited by pyrophosphate ;and (e) addition of other nucleoside triphosphates has no effect on the patternof labelling with ATP and CTP.In an attempt to purify the enzyme fraction responsible for terminalincorporation of nucleotidess2 it has been shown that the system can befractionated from rat liver along with the sRNA into three enzymicallyactive ribonucleoproteins designated a, (3, and y.62*83 Each of these has inturn been separated into an enzyme component and an sRNA componentin which base pairing appears to be significant since in all cases the ratio of83 E.Herbert and E. S. Canellakis, Biochirn. Biophys. Ada, 1960, 42, 363; Fed.Proc., 1960, 19, 318; E. Herbert, Biochem. J . , 1960, 77, 1 4 ~ DAVIDSON BIOSYNTHESIS OF NUCLEIC ACIDS. 363pseudouridylic acid (the 5'-phosphate of 5-ribosyluracil) plus uridylicacid to adenylic acid, and of cytidylic acid to guanylic acid, is close tounity.84While most work on the terminal incorporation of nucleotides into RNAhas been carried out with sRNA derived from liver tissue,~~66~7*~79~80~similar systems are also present in other tissues.For example, an enzymehas been purified from chick embryos which stimulates the terminal in-corporation of 14C-ATP into RNA without being affected by addition ofCTP, UTP, and GTP.= Disrupted calf-thymus nuclei have yielded anenzyme fraction which in presence of Mg++ and ATP (or an ATP-generatingsystem) stimulates incorporation of both ribonucleotides and deoxyribo-nucleotides into a polynucleotide-like material.73 The process is inhibitedby deoxyribonuclease but not by ribonuclease, and the product labelled byincorporation of 14C-CTP shows most of its radioactivity in the form ofterminal CMP. This product appears to resemble Hurwitz's hybrid poly-nucleotide already referred to.l* A similar enzyme has been purified fromcalf-thymus nuclei which, in presence of Mg++, stimulates incorporation ofCTP into the terminal position in RNA with the release of pyrophosphate,provided that the RNA is derived from thymuss6 RNA from most othersources is without effect, but RNA from Esch.coli can partly (10%) replacethymus RNA. The enzyme, however, can be replaced by a partly purifiedenzyme fraction from Esch. coli.Another enzyme fraction from Esch. coli catalyses the terminal incorpor-ation of 14C-ATP into the sRNA of the same organism.71 This incorpor-ation is unaffected by the presence of UTP, GTP, or deoxyribonuclease butis sensitive to ribonuclease. On the other hand the incorporation of 32P-UTPby Esch.coli preparations is dependent on the addition of ATP, GTP, andCTP and is prevented both by ribonuclease and by deoxyribon~clease.~~ Inthis reaction Esch. coli RNA does not act as nucleotide acceptor but thepresence of DNA from thymus, liver nuclei, or bacteriophage T2 is essential.The reason for the DNA-dependence and the nature of the product formedare obscure, but the product does not appear to be a mixed polynucleotideof the type already mentioned l8 since alkaline hydrolysis yields all fourexpected ribonucleotides, all labelled with 32P. This random distribution oflabel excludes simple terminal addition of the 32P-UTP.Terminal addition of UMP units to RNA chains can, however, be readilyaccomplished by enzyme systems present in extracts of Ehrlich ascitescarcinoma cell^.^^*^* The process is inhibited by pyrophosphate and requirespreliminary phosphorylation of uridine to the triphosphate level.Suchextracts also bring about non-terminal incorporation (see below).Non-terminal incorporation of nucleotide units into RNA. While in-corporation of nucleotide units on the ends of existing RNA chains clearlydoes not represent true polynucleotide biosynthesis, incorporation of nucleo-tides into non-terminal positions in polynucleotide chains must represent8 4 E. S. Canellakis and E. Herbert, Proc. Nut. Acad. Sci. U.S.A., 1960, 46, 170.89 C. W. Chung, H. R. Mahler. and M. Enrione, J . Biol Chem., 1960, 235, 1448.pG J. Hunvitz, A. Bresler, and A.Kaye, Biochem. Biophys. Res. Comm., 1959, 1, 3;M. ;\lexander, A. Bresler, J. Furth, and J. Hurwitz, Fed. Proc., 1960, 19, 318364 BIOLOGICAL CHEMISTRY.either a more radical extension of the chains or formation of new chains, ifthe unlikely possibility of simple exchange is excluded. Such non-terminalincorporations have been reported by a number of authors.69,74,76~77~78~85*87-The picture is at present confused and requires clarification by the co-ordination of the results obtained by various groups of workers.Terminal and non-terminal incorporation can readily be distinguishedby alkaline hydrolysis of the product after incorporation of a radioactivenucleotide. Alkaline fission (broken lines in IV) yields a mixture of nucleo-X Y Z U * Q U * R Sside-3’(2’) monophosphates together with a single nucleoside derived fromthe terminal nucleotide unit.If, for example, UMP labelled with 14C or 3Hin the uracil portion is incorporated terminally into a ribopolynucleotidechain, the single nucleoside liberated on alkaline hydrolysis will be radio-active. If it is incorporated non-terminally, radioactive uridine-3’(2’)monophosphate will be released by alkali (IVb).If the uridine-5’ monophosphate unit incorporated is labelled with 32P,the uridine released by alkali after terminal incorporation will, of course,not be radioactive but the nucleoside-3’(2’) monophosphate in the pen-ultimate position in the chain (containing the base 2 in IVa) will be labelledwith 32P. After non-terminal incorporation of uridine-5’ monophosphate,the uridine-3’ (2’) monophosphate released by alkali will be non-radioactivebut the nucleoside-3’(2’) monophosphate released from the adjacent positionin the chain (carrying the base Q in IVb) will be radioactive.This argumentis, of course, based on the assumption (which can be supported on othergrounds) that polynucleotide chains are extended at the end carrying anucleoside unit not substituted in position 3’ of the ribose residue.Canellakis 68 showed in 1957 that 14C-UMP could be incorporated into aribopolynucleotide by a soluble enzyme system in rat liver in the presenceof Mg++ and a phosphorylating system. Incorporation took place in a non-terminal position since alkaline hydrolysis yielded radioactive uridine-3‘(2’) monophosphat e.Cell-free extracts of osmotically disrupted Ehrlich ascites carcinoma cellsalso contain kinases for the phosphorylation of uridine and enzyme systemsresponsible for the incorporation of a UMP unit into RNA.Incorporationtakes place both terminally and n~n-terrninally.~~~~~’~~ Pyrophosphate de-87 M. Edmonds and R. Abrams, J . Biol. Chem., 1960, 235, 1142.88 C. W, Chung and H. R. Mahler, Biochem. Biophys. Res. Comm., 1959, 1, 232.89 S. B. Weiss, Proc. Nut. Acad. Sci. U.S.A., 1960, 46, 1020.90 A. Stevens, Biochem. Biophys. Res. Comm., 1960, 3, 92.91 E. Goldwasser, J . Amev. Chem. Soc., 1955, 77, 6083.g2 R. H. Burdon and R. M. S. Smellie, Biochem. J., 1960, 76, 2 1 ~ DAVIDSON BIOSYNTHESIS OF NUCLEIC ACIDS. 365presses terminal incorporation whereas orthophosphate depresses non-terminal incorporation.Some (about 20%) of the incorporated uridine isaminated to cytidine and appears as a CMP residue both terminally and non-terminally.Optimal incorporation of uridine requires the presence of a mixtureeither of glucose, DPN, and UTP or of TPN and DPNH, the effect of whichis to increase UTP formation and to promote terminal incorporation. In-creased incorporation is also brought about by the presence in the reactionmixture of low concentrations of ADP, GDP, and CDP, or of GTP andCTP, and by the addition of microsomal RNA. In the presence of Mg++,TPN, DPNH, ATP, GTP, CTP, and UTP, net synthesis of RNA (up to20%) has been demonstrated by use of the enzyme system from ascitescarcinoma cells.77778Net synthesis of RNA has also been demonstrated with an enzymesystem prepared by fractionation of ascites carcinoma extracts by am-monium sulphate.This system promotes the incorporation of 32P-UTPinto RNA in presence of DPNH. The reaction is stimulated by addition ofATP, GTP, and CTP and is inhibited by inorganic pyrophosphate. Thedistribution of 32P in alkaline hydrolysates indicates random distribution ofthe uridine residue, but when ATP, GTP, and CTP are omitted, a highproportion of the uridine residues is present as polyuridylic acid.93Withmost of these systems non-terminal incorporation of UMP residues pre-dominates but terminal incorporation is particularly noticeable with enzymesystems from brain and muscle.78Liver tissue contains an enzyme system, particularly abundant in thenuclear fraction, which promotes the incorporation of the nucleotides intoRNA from the nucleoside t r i p h o s p h a t e ~ .~ ~ ~ ~ ~ The reaction has been fol-lowed by using 32P-CTP or 32P-UTP or 32P-ATP. Incorporation of any oneof these is greatly increased by the addition of Mg++ and the other threenucleoside triphosphates ; the diphosphates are much less effective and thereaction is inhibited by pyrophosphate. Alkaline hydrolysis of the poly-nucleotide product yields nucleoside-3’(2’) monophosphates, all of whichare labelled. While this is strongly suggestive of non-terminal incorpor-ation, it does not exclude the possibility of terminal addition to differentend groups of different RNA’s present in the enzyme preparation, i.e.,where R in (IVb) might be A, G, U, or C.The 32P-RNA was thereforedigested with snake-venom diesterase which attacks RNA in stepwisefashion from the end of the chain carrying the nucleotide residue with afree 3’-hydroxyl group, liberating nucleoside-5’ monophosphates, whichwere dephosphorylated by venom phosphomonoesterase to yield nucleosidesand inorganic phosphate. Such treatment applied to terminally labelledRNA would release a high proportion of 32P-orthophosphate before muchof the chain had been degraded, but the 32P-RNA formed by the liver-enzyme system yielded 32P-orthophosphate and unlabelled orthophosphateat the same rate. The labelled substrate must therefore have been incor-porated throughout the entire polynucleotide chains9 The system is there-Similar enzyme systems are present in many mammalian tissues.93 R.H. Burdon, Biochem. J., 1960, 77, 1 4 ~ 366 BIOLOGICAL CHEMISTRY.fore very similar to that involved in DNA biosynthesis (see above). It ispeculiar in being activated by pre-incubation with deoxyribonuclease butnot ribonuclease. The location of such an enzyme system in the nuclearfraction of liver has been noted by other authors.70From calf-thymus nuclei an enzyme has been purified which promotesthe synthesis of a polyadenylic acid chain from 32P-ATP or 14C-ATP.74s87From the ratio of 14C as adenosine to 14C as adenosine-3'(2') monophosphateand from similar data for 32P distribution after hydrolysis, it has been con-cluded that the chain formed consists of a linear sequence of 25-100 AMPunits.No primer requirement has been found and the system does notutilise UTP or GTP, but a similar though separate enzyme system forincorporating CTP to form a polycytidylic acid has also been purified fromthymus nuclei. For this system a primer polynucleotide is necessary.74Evidence has also been presented for the presence in bone marrow andEhrlich ascites cells of a similar system promoting incorporation of ATP intopol ynucleo t ide. 69Crude preparations from chick embryo contain an enzyme system,already mentioned, which promotes terminal incorporationJs5 but from suchextracts a second system has been isolated, which promotes the incorpor-ation of AMP units into RNA in non-terminal positions adjacent to any ofthe other three monomeric ~ n i t s .~ 5 r ~ a ~ ~ Again the substrates utilised arethe nucleoside triphosphates, and pyrophosphate is released ; Mg++ andprimer polynucleotide are required. The operation of the system can bedemonstrated by the incorporation of 32P-pyrophosphate into nucleosidetriphosphates in presence of added RNA.=yg5The same type of mechanism has also been reported in extracts of Esch.coli which in presence of Mg++ can promote incorporation of AMP unitsfrom 32P-ATP into RNA in internucleotide linkage, provided that the otherthree nucleoside triphosphates are also presentIt appears therefore from the results of observations on a wide varietyof biological materials, including ascites carcinoma cells,93 liver 89chick e m b r y 0 , 8 ~ ~ ~ ~ ~ ~ and Esclz.coZi,m that RNA can be synthesised by areaction very like that involved in DNA biosynthesis, in which the sub-strates are the ribonucleoside triphosphates , Mg++ is required, and pyro-phosphate is eliminated.Conclusion.-Four main mechanisms have been described for the bio-synthesis of nucleic acids: (a) the DNA polymerase system which utilisesdeoxyribonucleoside triphosphates as substrates ; (b) a similar system forRNA biosynthesis which utilises ribonucleoside triphosphates as substrates ;(c) the enzyme system involved in the formation of the terminal nucleotidesequence in sRNA ; and (d) polynucleotide phosphorylase, which utilisesnucleoside diphosphates as substrates.J.N. D.M C. W. Chung, Fed. Proc., 1958. 17, 201.95 C. W. Chung and H. R. Mahler, J . Amer. Chem. SOL, 1958, 80, 3165MCILWAIN : NEUROCHEMISTRY : MAINTENANCE AND EXCITATION. 3673. NEUROCHEMISTRY : NEURAL MAINTENANCE AND EXCITATIONCHEMICAL techniques have been applied widely in investigation of neuralsystems since the term Nervenchemie was used in the last century. Recentaccounts carrying introductions to literature 2 ~ 3 include among some 30divisions of the subject : the composition of neural tissues; their meta-bolism ; chemical factors in neural transmission and in electrophysiology ;interactions between neural systems and the rest of the anirnal body onmetabolic and endocrinological levels ; and the chemical pathology andpharmacology of neural ~ y s t e m .~A great variety of neural systems exists in the animal kingdom, diversechemically as well as anatomically; but much current work is interestingthrough the connections which it affords between systems as diverse as thegiant axons of marine invertebrates and the finely ramifying neurons of themammalian brain. Neural tissues of higher animals consume energy-yield-ing substrates at much the same rate as do muscles in yielding mechanicalwork, the kidneys in performing osmotic work, or the liver in chemicalsynthesis: yet the neural systems have no comparably obvious output. Thenerve impulse itself involves little energy but it and the neurons carrying itare the units of the most sensitive, most rapidly acting, and most complexsystem of the animal body; much neural metabolism is concerned withmaintaining structure and readiness to react.The theme of neural main-tenance and excitation has therefore been chosen in introducing the subjectof neurochemistry to these Reports.Maintenance.-Energy-yielding and associated processes are consideredfirst, and subsequently the main energy-consuming processes: those of main-taining the differential ion concentrations on which neural action depends.The majority of material exchange betweenthe mammalian nervous system and the rest of the body takes place by theblood stream; in the case of the brain, analysis of blood entering and leavingit is adequate to detect the substrates which contribute most immediatelyto its maintenance.Recent observation and appraisal confirm that oxygenand glucose meet the main energy requirements, yielding carbon dioxide;small changes in lactic and pyruvic acid content have been noted.5~6 Use1 J. E. Schlossberger, “ Erster Versuch einer Allgemeine und Vergleichenden Thier-Chemie,” Winter, Leipzig, 1856.H. McIlwain, “ Neurochemistry,” Lectures on the Scientific Basis of Medicine,6, Athlone Press, London, 1958.H. McIlwain, “ Biochemistry and the Central Nervous System,” Churchill,London, 1959.K. A. C. Elliott, H. I. Page, and H. I. Quastel (eds.), “ Neurochemistry,” Thomas,Springfield, 1955; S. R. Korey a n t J. I. Nurnberger (eds.), “ Neurochemistry,” Casse!:London, 1956; H. Waelsch (ed.),Proc.1st Internat. Neurochem. Symp., Academic Press, New York, 1955; D. Richter(ed.), “ Metabolism of the Nervous System,” Proc. 2nd Internat. Neurochem. Symp.,London, 1957; H. McIlwain, “ Chemotherapy and the Central Nervous System,”Churchill, London, 1957 ; H. McIlwain and R. Rodnight, “ Practical Neurochemistry,”Churchill, London, 1961.5 G. G. Rowe, G. M. Maxwell, C. A. Castillo, D. J. Freeman, and C. W. Crumpton,J . Clin. Inv., 1959, 38, 2154; R. Rodnight, H. McIlwain, and M. A. Tresize, J . Neuro-chem., 1959, 3, 209; H. Lennartz and R. Seifert, Klin. Wochsckr., 1959, 37, 296; K. V.Coxon and R. J. Robinson, J . Physiol., 1960, 147, 487.Glwose and amino-acids.Biochemistry of the Developing Nervous System,6 D. B. Tower, “ The Neurochemistry of Epilepsy,” Thomas, Springfield, 1960368 BIOLOGICAL CHEMISTRY.of [14C]glucose, and analysis of the brain itself or of cerebral tissue, show,however, not only the labelling of intermediates of the tricarboxylic acidcycle but also extensive exchange with amino-acids,6-8 especially glutamicacid, glutamine, aspartic acid, asparagine, and y-aminobutyric acid, whichoccur in the brain at relatively high concentration.N-Acetylaspartic acid, inwhich also the brain is relatively rich, did not undergo rapid exchange; 8 withthe other amino-acids, exchange occurred also with pyruvate as ~ubstrate.~Transamination affords enzymic basis for such interchange ; that withglutamic and oxaloacetic acid is potent in neural as in other tissues, but morecharacteristic of cerebral tissues are the links through y-aminobutyric acid lowhich in effect provide an alternative route between ketoglutarate andsuccinate in the tricarboxylic cycle.Little y-aminobutyrate exists in mostorgans of the body but the brain contains 4-46 pmoleslg., and cerebraltissues are unusual also in their content (i) of the decarboxylase, whichproduces it from glutamic acid l1 at about 35 pmoles per g. of tissue per hr.,and (ii) of the y-aminobutyrate-oc-ketoglutarate transaminase,12JS operatingat 10-60 &moles per g. of tissue per hr. and yielding succinsemialdehyde,subsequently oxidised to succinate.13 Administration of [14C]glutamate tomice,14 or its addition to cerebral tissue in v i t ~ o , ~ leads promptly to theappearance of y-aminop4C]butyrate, [14C]aspartate, and WO,.At a slowerrate, F*C]proline added at the brain in vivo yields glutamic and aspartic acid,and alanine.13Metabolism of y-aminobutyrate appears essential for normal cerebralfunctioning. The decarboxylase and transaminase which form and removey-aminobutyrate require pyridoxal phosphate and, in the epileptiformconditions which result from pyridoxal deficiency, cerebral y-aminobutyratediminishes. This occurs also in convulsions caused by isonicotinoyl-hydrazine and -thiosemicarbazide (which inactivate pyridoxal by forminghydrazides) and by the inhibitory analogue deoxypyridoxine.1° y-Amino-butyrate has proved too versatile a substance for a simple reason to be givenas basis for these phenomena. Respiration of the brain or of cerebraltissues is depressed in the pyridoxine-deficiencies referred to,6 suggestingthat its oxidative route is important; a role in transmission is also proposed(see below).Urea, guanidines, and phosphagens. Urea, isolated as its dixanth-hydryl derivative, has been proved to be produced at the brain of the ratin vivo from 1%-labelled arginine; l6 it is present in greater concentration in7 A.Beloff-Chain. R. Catanzavo. E. B. Chain, I. Masi, and F. Pocohiari, Proc. Roy.Soc., 1955, B. 144, 22:8 A. Geiger, N. Horvath, and Y. Kawakita, J . Neurochem., 1960,5, 311; A. Geiger,Y. Kawakita. and S. S. Barkulis, ibid., p. 323; S. S. Barkulis, A. Geiger, Y. Kawakita,and V. Aguiler, ibid., p. 339.9 A. D. Freedman, P. Ry‘rnsey, and S. Graff, J .Biol. Chem., 1960, 235, 1854.10 (a) E. Roberts (ed.),Acid,” Pergamon, London, 1960; (b) R. 0. Brady and D. B. Tower (eds.),chemistry of Nucleotides and Aminoacids,” Wiley, New York, 1960.l1 E. Roberts and S. Frankel, J . Biol. Chem., 1951, 190, 505.l2 C. F. Baxter and E. Roberts, J . Biol. Ckem., 1958, 232, 1135.l 3 R. W. Albers, in ref. lob, p. 146.11 A. Lajtha, S. Berl, and H. Waelsch, J . Neurochem., 1959, 4, 322.l5 M. B. Sporn, W. Dingman, and A. Defalco, J . Neurochem., 1959, 4, 141; W.Inhibition in the Nervous System and y-4,minobutyricThe Neuro-Dingman and M. B. Sporn, ibid., p. 148MCILWAIN : NEUROCHEMISTRY : MAINTENANCE AND EXCITATION. 369the rabbit brain (based on tissue water) than in the animal’s blood plasma.16Enzymic basis for the synthesis is given by the demonstration of arginase incerebral tissue, yielding 7-12 pmoles of urea per g.per hr.17 Moreover,the tissue contained arginosuccinase, yielding 1-3 pmoles of arginine andfumaric acid per g. per hr. from arginosuccinic acid.17 This acid waspreviously recognised as an intermediate in the production of arginine fromcitrulline in other organs but does not normally accumulate in appreciableamounts; its abundant excretion in the urine of subjects suffering a raremental defect was thus surprising.lg The defectives’ plasma and urinaryurea were normal; the concentration of arginosuccinic acid in the cerebro-spinal fluid was greater than that in the blood, and the arginosuccinic acidexcreted corresponded to about 1 pmole per g.of brain per hr.: a cerebralorigin for the acid is thus suggested.Cerebral tissues have been examined systematically for simple mono-substituted guanidines ; l9 those found were all derived from amino-acids,being (mp moles per g. of guinea-pig brain) : arginine, 100; y-guanidobutyricacid,lO 50; glycocyamine and taurocyamine, 30 each. (The mammalianbrain is rich in taurine and related substances.20) Several guanidino-acidsand amino-acids affect the electrical activity of the brain when applied to itssurface.21Arginine phosphate constitutes a major phosphagen of the nerves of cer-tain invertebrates ; other aspects of their composition have been examined.22In the mammalian brain some indication has been given that the guanidino-acids named above exist partly in a combined but the major cerebralphosphagen is phosphocreatine.3*23 Aspects of its role in the control ofmetabolism have been 24 Diminution of phosphocreatine in isolatedcerebral tissue is caused by addition of glutamic acid, and is attributable tothe utilisation of energy-rich phosphate in the synthesis of glutamine; 25 itis associated with a fall in membrane potential.% Aspartic and y-amino-butyric acid also diminish the phosphocreatine content, apparently by theirconversion into glutamic acid by routes outlined above.One importantresult of the synthesis of glutamine is the removal of a m r n ~ n i a , ~ ~ ~ J ~ ~ foraccumulation of ammonia is associated with certain convulsive condition^.^, 27It can also be suggested 25 that the synthesis is the basis for an additionaluptake of potassium salts by cerebral tissues28 which does not, however,appear to afford the basis for the tissue’s major ion turnover described below.l6 H.Davson and C. R. Kleeman, personal communication.l7 S. Tomlinson and R. G. Westall, Nature, 1960, 188, 235.l8 J. D. Allan, D. C. Cusworth, C. E. Dent, and K. V. Wilson, Lancet, 1958, I, 182.2o D. B. Hope, Proc. 4th Internat. Congr. Biochem., 1959, 13, 63.21 D. P. Purpura, M. Girado, T. G. Smith, D. A. Callan, and H. Grundfest, J . Neuro-*2 G. G. J. Deffner and R. E. Hafter, Biochim. Biophys. Ada, 1960, 42, 189,23 P. J. Heald, “ Phosphorus Metabolism of Brain,” Pergamon, London, 1960.24 H. McIlwain, in Ciba Foundation Symposium, “ Regulation of Cell Metabolism,”26 R.J. Woodman and H. McIlwain, Bioclzem. J., in the press.26 H. H. Hillman and H. McIlwain, J. Physiol., 1960, 152, 5 9 ~ .27 M. Kurokawa, J. Neurochem., 1960, 6, 368.2a C. Terner, L. V. Eggleston, and H. A. Krebs, Bioclzeni. J . , 1950, 47, 139.J. P. Blass, Bioclzem. J., 1960, 17, 484; Thesis, London, 1960.chem., 1959, 3, 238.2220.Churchill, London, 1959, p. 127370 BIOLOGICAL CHEMISTRY.Distribution of ions and eZectrica2 charge. Although a neural organ suchas the brain can often be regarded as a whole, as was done in the precedingsections, other questions demand study on a smaller scale. The unit is thenerve cell: from cerebral tissue, cells can be teased out for analysis 29 ormetabolic and can be penetrated by micro electrode^.^^ Experi-mentally more accessible are the giant nerve fibres of certain animals includ-ing the squid, which have given many of the following data.32 The neuronemembrane shows a high electrical resistance of some 1000 f2/cm.2 andcapacity of about 1 pP/cm.2, consistent with the properties of a doublelayer of oriented lipid molecules, as is also the electron-microscopic appear-ance of several types of nerve fibre, which exhibit outer membranes 50-100 in thickness.%The membrane separates the cell interior, relatively high in K+ but lowin Na+ and C1-, from the cell exterior which is low in K+ and high in Na+and Cl- (for specific values in different neural systems, see refs.3, 6, 32,34, 35). The small but finite conductance quoted above corresponds to anappreciable permeability of the membrane to ions which is increased onexcitation (see below) .32,35 Thus to maintain the differential concentrationsquoted, processes resulting in extrusion of Na+ and absorption of K+ areconstantly in progress, movements of some 0.1 pmole of the ions per cm.2of surface per hr.occurring in the squid axon.32,34*36 In isolated cerebraltissues under good metabolic conditions and stable in potassium content,use of 42K showed some 3-5% of the tissue content to be exchanging permin., corresponding to a movement of 400 microequiv. of K per g. of tissueper hr.37Another indication of the permeability of normal neural tissues topotassium salts is the existence of a resting membrane potential comparablein magnitude to that given by applying the Nernst equation to the differentialconcentration of potassium salts: the interior of most nerve cells is 50-100 mv negative with respect to the e ~ t e r i o r .~ ~ , ~ This applies also toisolated cerebral tissues 26,31 which, furthermore, lose their membranepotential on increasing the external potassium concentration. This normalmembrane potential is, on the other hand, incompatible with comparablepermeability of the neurone to sodium; the ratio of the permeabilities forsodium and potassium in the giant axon 32 is about 1 : 100. Sodium enter-ing during activity is, however, extruded despite the contrary concentrationgradient; but for this and the concomitant uptake of potassium, energy-yielding processes are required.Thus efflux of sodium from the giant axon29 0. H. Lowry, J . Histochem. Cytochem., 1953, 1, 420; see also ref. 3.30 H. Hyden and A. Pigon, J . Neurochem., 1960, 6, 57.31 C-L. Li and H. McIlwain, J . Physiol., 1957, 139, 178.a2 A. L. Hodgkin, Proc. Boy. Soc., 1958, B, 148, 1.33 J. D. Robertson, J . Biophys. Biochem. Cytol., 1958, 4, 349; Biochemical SocietySymposium No. 16, Cambridge University Press, 1959, 16, 3; E. G. Gray, Nature, 1959,183, 1592.34 A. M. Shanes, Pharmcol. Rev., 1958, 10, 61, 165.35 A. F. Huxley, 4nn. N.Y. Acad. Sci., 1959, 80, 221.36 E. J. Harris, Transport and Accumulation in Biological Systems,” Butter-“(a) H. A. Krebs, L. V. Eggleston, and C. Terner, Biochem. J ., 1951, 48, 530;worth, London, 1960.( b ) J. T. Cummins and H. McIlwain, ibid., 1960, 76, 6 4 ~ MCILWAIN : NEUROCHEMISTRY : MAINTENANCE AND EXCITATION. 37 1after injection of =Na is inhibited by azide, cyanide, or 2,4-dinitrophenol 32938and when inhibited by 2-millimolar cyanide is in part restored by injectionof adenosine triphosphate into the axon. This enabled the amount ofsodium extruded after a given dose of energy-rich phosphate (-P) to beestimated, affording a Na/-P ratio of 0.67. Further results of this type havebeen obtained by measurements during recovery after excitation, as describedbelow.Osmotic workis performed by most cells and tissues and results in potential differencesbetween their interior and exterior. More characteristic of nerve cells arethe events which follow a change in resting potential, caused by chemical orelectrical means.These events have been measured in detail and expressedmathematically, the analysis being based on a fundamental observationthat neural permeability to sodium and potassium depended on membranepotential and was independent of membrane current .32935 After diminutionin resting potential by some 20 mv two successive changes rapidly ensue.(a) Membrane conductance first increases, by a factor of about 40,current flows into the nerve, and within a millisecond the interior becomespositive, approaching the potential to be expected from the distributionof Na+ inside and outside the fibre. This is attributed to a change in theneural membrane which greatly increases its permeability specifically tosodium; the entering current is lacking if solutions outside lack sodium.Absence of sodium makes many excitable tissues non-responsive ,32 includingcerebral tissues.39 In electrical terms the changed permeability results in aflow of current, which diminishes the membrane potential of adjacent regionsbeyond that first involved. This diminution in potential again causesincreased permeability and current flow, so that the phenomenon spreadsalong the nerve.The increase in sodium conductance with fall in membranepotential is thus fundamental to neural transmission. It has been attributedto movements of charged membrane components, or to changed configurationat membrane-pores.m In explanation of effects of Ca++ on permeability,these components or pores are pictured to be normally associated with Ca++,which itself enters the fibre to a small extent on excitati0n.a(b) In a normal neurone, processes (a) are observed to be followed, atany one point on the nerve and within a fraction of a millisecond, by afurther group of changes which restore membrane potential.Potassiumconductance of the membrane increases by a factor of about 100, permittingan outflow of K+ which exceeds the influx of Na+ and so again leaves theinterior of the membrane with a negative charge. When the potentialapproaches that (-50 to -100 mv) normal for the neuron, potassium con-ductance falls. This increased permeability of the membrane to potassiumis also attributed to a movement of membrane constituents, quantitativedata being consistent with movement of the outgoing potassium by a pathwhich requires the juxtaposition of 4 charged particles, conceivably in a fine38 A.L. Hodgkin and R. D. Keynes, J . Physiol., 1955, 128, 28, 61; P. C. Caldwell,A. L. Hodgkin, R. D. Keynes, and T. I. Shaw, J . Physiol., 1960,152, 561.39 M. B. R. Gore and H. McIlwain, J , Physiol., 1952, 117, 471.40 L. J. Mullins, J . Gen. Physiol., 1959, 42, 817, 1013.41 A. L. Hodgkin and R. D. Keynes, J . Physiol., 1957, 138, 253.Excitation and Recovery.-Ion movements on excitation372 BIOLOGICAL CHEMISTRY.‘ I pore.” 38*40 The extent of the efflux of K+ is small, membrane potentialand resistance being recovered at any one point on the fibre of the giantaxon in a few milliseconds, and briefer periods sufficing in mammalian nerves.The K+ movements giving recovery proceed along the fibre in the wake ofthe depolarisation, the two resulting in the action potential.The nerve has thus returned to its resting electrical condition, but hasgained Na+ and lost K+.The net ionic changes following the passage ofsome hundreds of impulses have been determined by direct analysis of neuraltissue and surrounding fluids. Sepia axons 38 lose about 4 pp equiv. of K+per cm.2 per impulse; a similar value in a Libinia fibre is equivalent to3 mp equiv. of K+ per g. of tissue per impulse.42 Mammalian cerebralcortex lost K+ on applying pulses at 100 per sec., at the rate of 240 pequiv.of K+ per g.per hr., giving a minimum loss of 0.7 mp equiv. per g. perimpulse.37b The changes quoted are the net result of influx and efflux ofeach ion, and by the use of 24Na and &K these movements have beenmeasured separately. In the systems just quoted, the additional potassiumefflux was 3-10 times the concomitant influx, the total efflux in mammaliancerebral cortex rising to 700 pequiv. per g. of tissue per hr.Initiation of discharge. The diminution of membrane potential whichinitiates the changes described, is conveniently arranged for experiment byelectrical means; that is, by the route normally involved in transmission.In vivo, initiation is ordinarily by other nerve fibres or at sensory nerveendings and evidence often favours a change in permeability as the means ofcausing the fall in membrane potential.& Permeability may in some in-stances be affected mechanically and in others chemically.Events in theretina, involving the visual pigments,@ in and in detecting motion 48have been reviewed recently.The apparatus by which a nerve affects a muscle or another nerve fibreis highly specialised structurally and chemically, and many potent drugsact at such junctional sites. Recent investigation of the cholinergic systemsof the brain exemplifies this, and has shown in parts of the brain a pattern,found elsewhere, of (i) synthesis of acetylcholine at the endings of onenerve, (ii) its release from that nerve on stimulation, and (iii) the stimulationof a second nerve, across the narrow synapse.by the liberated acetylcholine.Previous study had suggested acetylcholine to be “ synthesised into ” abound form:’ and differential and gradient density centrifugation indeedshowed both it and choline acetylase, the enzyme concerned in synthesis,t o coexist in particular subcellular fractions of ground cerebral tissue.48These fractions were shown by electron microscopy to be enriched in aspecific and quite elaborate type of structure.4g This was visible also on48 A. M. Shanes, J . G y , Physiol., 1951, 34, 795.43 J . A. B. Gray, in Neurophysiology,” 1, 123, American Physiological Society,44 R. Hubbard and A. Kropf, Ann. N.Y. Acad. Sci., 1959, 80, 388.45 Y. Zotterman, Ann. N . Y . Acad. Sci., 1959, 80, 358.46 W. R. Loewenstein, Ann.N.Y. Acad. Sci., 1959, 80, 367.47 W. Feldberg, Physiol. Rev., 1945, 25, 596.48 C. 0. Hebb and B. N. Smallman, J . Physiol., 1956, 134, 385; C. 0. Hebb and49 E. G. Gray, J . Anat., 1959, 93, 420; E. G. Gray and V. P. Whittaker, J . Physiol.,Washington, 1959.V. P. Whittaker, ibid., 1958, 142, 187.1960,153, 3 6 ~ MCILWAIN : NEUROCHEMISTRY : MAINTENANCE AND EXCITATION. 373examination of the tissue before grinding, and represented part of a synapticregion; the end of one nerve containing small mitochondria and a patternof vesicles, retaining attached to it part of the post-synaptic membrane.Addition of acetylcholine to sliced or to ground cerebral tissues alterscertain aspects of their phospholipid metabolism. For instance, inorganicp2P]phosphate was then incorporated to an increased extent in phospho-inositides and phosphatidic acids.50 A cerebral microsomal fraction carrieda kinase which synthesised the phosphatidic acids from diglycerides andadenosine triphosphate at a rate that was accelerated 40-90% by 10-100pM-acetykholine (an alternative synthetic route to the phosphatidic acidwas not similarly sensitive 51).The fraction carried also a phosphatidicacid phosphatase. It was proposed 52 that acetylcholine acted by causingdepolarisation and influx of sodium, and that the two enzymes participatedin the active extrusion of sodium. Rates observed for the two enzymesappear however to be about 1 pmole per g. of fresh tissue per hr., and thusto preclude appreciable contribution to active transport in the tissues as awhole, for transport of the order of 600 pequiv.per g. per hr. is required.37bConceivably the processes observed reflect a localised relation betweenacetylcholine and specifically the postsynaptic membrane or the synapticvesicles ; considerable physical movement, if not synthesis and breakdown,of membrane constituents must be involved in their formation and dis-charge.53including that ofelectric fishes which in special electric organs can generate potentials of100 v or more. Interesting attempts have been made to isolate the sub-stances with which acetylcholine interacts in discharging the electric organs,by employing substances which inhibit its action.55 Extracts from theorgan in Electrophorus were fractionated by ammonium sulphate and foundto yield a precipitate with curare at particular pH and ionic strength.Thetissue constituent concerned was stated to be a protein and to bind certaincholine derivatives, especially acetylcholine.Not all interactions between neurones are in the sense of one, presynaptic,causing excitation of a second, postsynaptic, cell; instead depression ofexcitability can r e ~ u l t . ~ * ~ , ~ ~ y-Aminobutyric acid may act as mediator ofsuch inhibitory impulses in certain crustacea,lOa in addition to having themetabolic importance in the brain referred to above.67 In the mammalianbrain also, some correlations between cerebral activities and level of y-amino-butyrate have led to proposals6J0" that the substance performs there aninhibitory role.Recovery.A period of maximal excitation of a neural system leads toAcetylcholine is important in many neural systemsL. E. Hokin and M. R. Hokin, Biochinz. Biofihys. Acta, 1955, 18, 102.61 M. R. Hokin and L. E. Hokin, J . Biol. Chem., 1959, 234, 1381, 1387.62 L. E. Hokin and M. R. Hokin, Internat. Rev. Neurobiol., 1960, 2, 99.53 H. McIlwain, Proc. 4th Internat. Neurochem. Symp., 1960.54 D. Nachmansohn, " Chemical and Molecular Basis of Nerve Activity," Academic55 C. Chagas, E. Penna-Franca, K. Nishie, and E. J. Garcia, Arch. Biochenz. BiojWzys.,57 E. Roberts and E. Eidelberg, Internat. Rev. Neuvobiol., 1960, 2, 279.Press, New York, 1959.1958, '95, 251; S. Ehrenpreis, Science, 1959, 129, 16,13.J.C. Eccles, '' The Physiology of Nerve Cells, University Press, Oxford, 1957374 BIOLOGICAL CBEMlSTRY.considerable change, not only in sodium and potassium, but also in manyassociated material~.~9~~ A group of such changes in cerebral tissue (derivedfrom three separate investigations) 37959 is shown in Fig. 1; after a fewminutes' stimulation a new equilibrium state is reached in which the tissuehas about 70% of its original potassium content and has little phospho-creatine, but shows increased rates of respiration and glycolysis. Theseincreased rates are attributed 3958,60 to increase in inorganic phosphate andphosphate acceptors which can be limiting intermediates in respiration andI206 0t *I I 6oL 5 0390UA 8 0 30 6 0Time (seconds)Changes in cerebral cortical tissue during and after electrical stimulation in vitro(cf.refs. 37, 59).1,2,3,4,Respiration (pmoles of oxygen per g. per hr.).Inorganic phosphate (pvnoles per g.).Adenosine triphosphate (pmoles ger g.).Phosphocreatine (pmoles per g.), (a) after 7 seconds' stimulation, (b) after 20 minutes'A, Before stimulation.B, During stimulation.Abscissae give time after stimulation has stopped.stimulation.5, Potassium (pequiv. per g.) , after 20 minutes' stimulation.glycolysis ; and the increased phosphate to the utilisation of energy-richphosphate in ion transport. An indication of the speed and relation be-tween these processes is given by events when stimulation is stopped. Ifstimulation has been for a brief period only, phosphocreatine is resynthesisedrapidly, at a maximum speed of 150 pmoles per g.per hr. However, ifpulses have been applied for some 20 min. resynthesis occurs more slowly,little being regained during the first 30 sec. It is during this period that themost rapid reassimilation of potassium takes place when, after pulses have58 H. McIlwain, Physiol. Rev., 1956, 36, 355.s9 H. McIlwain, J . Physiol., 1954, 124, 117; P. J. Heald, Biochem. J., 1954, 57, 673.6o H. McIlwain, Proc. 2nd Internat. Neurochem. Symp., London, 1957MCILWAIN : NEUROCHEMISTRY : MAINTENANCE AND EXCITATION. 375been applied for some minutes, the 12 pequiv. of potassium per g. of tissuewhich have been lost are in the course of being reabsorbed: reassimilationtakes place at a maximum rate of about 600 pequiv.per g. per hr. Thedata suggest 37b a K/-P ratio of about 1 and the performance of osmoticwork equivalent to 18% of the additional free energy supplied. The squidaxon after stimulation extruded 30 pequiv. of sodium per g. per hr., whichwas estimated to require 10% of the energy supplied by its resting respir-ation.61Few neural enzymes react with energy-rich phosphates at speeds adequateto form a basis for these processes, but the properties of adenosine triphos-phatases are relevant.60 The rates required in cerebral tissues probablyinvolve about 500-1000 pmoles of -P per g. per hr., and adenosine tri-phosphatases from this source have been observed capable of causing lossof 800-2000 pmoles of the triphosphate per g.per hr.; 62 more than oneenzyme is involved. In certain neural preparations the enzyme has aninterestingly relevant sensitivity to ions. Finely particulate material fromcrab nerve contained an adenosine triphosphatase whose action was acceler-ated by magnesium or sodium or by low concentrations of potassium; itwas inhibited by calcium and by higher concentrations of potassium, thepotassium and sodium then competing for a common site.63 Some analogousproperties are shown by adenosine triphosphatases of cerebral preparations,Mincluding fractions likely to be derived from membrane structures.Adenosine triphosphatases can be incorporated into mechanisms ofactive transport in many ways; some of these are analogous to the role ofthe enzyme in muscle and others involve phosphorylating a hypotheticalion-carrier or membrane component.One general sequence with such acomponent (Y; conceivably part of the enzyme itself) is: 6oOf known cerebral reactions of this type, that leading to incorporation of32P of ATP into phosphoprotein 23 is relevant and can proceed at rates ofat least 400 pmoles per g. of tissue per hr. Although this reaction in cerebraltissues was specifically stated to have been differentiated from that ofadenosine triphosphatase on the basis of fluoride i n h i b i t i ~ n , ~ ~ this does notpreclude it from forming part of an adenosine triphosphatase comprising aseries of linked steps, as (l), (a), above, of which only one is fluoride-sensitive,especially as the different cerebral adenosine triphosphatases could differin fluoride sensitivity.The phosphoprotein was found to be attached tostructures which were not nuclei or mitochondria. Mechanisms utilisingadenosine triphosphate in ion transport need not, however, involve aneasily isolable phosphorylated intermediate.Characterisation of other neural constituents involved in ion selection ortransport is given in the following section.Newly Recognized Constituents in Excitation and Recovery.-The normal(I) ATP + Y ADP + YP (2) YP __)_ Y + PR1 A. L. Hodgkin and R. D. Keynes, Symp. Soc. exp. Biol., 1954, 8, 423.62 M. B. R. Gore, Biochern. J., 1951, 50, 18.63 J. C. Skou, Biochirn. Biophys. Acta, 1957, 23, 394; 1960, 42, 6.61 H. Hess and A. Pope, Fed.PYOC., 1957, 16, 196; J . Jarnefelt, Biochim. Biophys.,Ada, 1961, 48, 104, 111; D. H. Deul and H. McIlwain, unpublished work376 BlOLOGICAL CHEMISTRY.response of isolated cerebral tissues to electrical excitation (Fig. 1) is lostwhen the tissues are kept in cold media 85 but can be restored by incubatingthem with certain tissue extracts or blood-plasma preparations. Theplasma fractions which were active contained glycoproteins and theirpotency was correlated with their content of neuraminic acid derivatives.66Activity in restoring excitability was shown by other neuraminic acidderivatives and was greatest in preparations of cerebral gangliosides 66which acted at 0.1 mg./ml. The inactive condition was found to be due tomigration of basic proteins from the neurone nuclei to elsewhere in theand could be reproduced by addition of other basic proteins andpeptides to normal cerebral t i s s u e ~ .~ ~ , ~ ~ Both basic proteins 69 and ganglio-sides 70 became attached to the tissue during these interactions; the quantityof gangliosides required as antagonist approximated to the quantity nativeto the tissue.66When normal cerebral tissues were ground and fractionated by differentialand density-gradient centrifugation, gangliosides were found in greatestquantities in fractions derived from membranes of the cell boundary or itsendoplasmic reticulum,71 and these fractions possessed greatest ability tocombine with basic proteins.72 Protamines were among the most potentof the basic proteins and inhibited, not only the respiratory response of thetissue to excitation, but also the loss of phosphocreatine shown in Fig.1,implying diminution in energy-consuming reactions. Protamines werewithout effect on the loss of K+ during excitation but inhibited its subse-quent reassimilation 73 and thus acted at a major system concerned with ion-selection or active transport. The gangliosides thus appeared to be part ofsuch a system.73Other properties of gangliosides which indicate a role in neural activitiesconcern a bacterial toxin and a virus. Tetanus toxin owes its spectaculareffects to action at motor or associated neurons of the central nervoussy~tem.~q Mixing the crude75 or purifiedT6 toxin with suspensions ofcerebral tissue, and filtering, gives a fluid of diminished toxicity.Prepar-ations of cerebral lipids, especially sphingolipids, could be substituted forthe tissue suspension and the most active fraction contained gangli~sides.~~The toxin protein and the gangliosides were shown by ultracentrifugal andelectrophoretic examination to form complexes, which however remainedsoluble unless calcium salts and a cerebroside or sphingomyelin werepresent. Purified ganglioside fractions proved highly active, their potency65 N. Marks and H. McIlwain, Biochew. J., 1959, 73, 401.66 H. McIlwain, Biochem. J., 1960, 76, 1 6 ~ ; 1961, 78, 24.67 H. McIlwain, Biochem. J., 1959, '73, 514.68 H. McIlwain, J . Physiol., 1960, 152, 6 0 ~ .69 C. G. Thomson and H. McIlwain, Biochem. J., 1961, 79, 342.70 S.Balakrishnan and H. McIlwain, Biochem. J., in the press.71 L. S. Wolfe, Biochem. J., 1960, '77, 9 ~ .7 2 L. S. Wolfe and H. McIlwain, Biochem. J., 1960, 76, 6 5 ~ ; 1961, 78, 33.73 J. T. Cummins, H. McIlwain, and R. J. Woodman, unpublished work.74 V. B. Brooks, D. R. Curtis, and J. C . Eccles, J. Physiol., 1957, 135, 655.75 A. Wasserman and T. Takaki, Berlin. Klin. Wochschr., 1898, 35, 5; K. Land-7* A. J. Fulthorpe, J. Hyg., 1956, 54, 315.77 W. E. van Heyningen, J . Gen. Microbiol., 1959, 20, 291, 301, 310.steiner and A. Botteri, Zentr. Baht. (Orig.). 1906, 42, 562MCILWAIN : NEUROCHEMISTRY MAINTENANCE AND EXCITATION. 377varying with N-acetylneuraminic acid content (see below) between 950 and1300 receptor units/mg., implying combination of 1 mg.of ganglioside with20 mg. of toxin, of which mg. is lethal to a mouse. Combinationrequired the N-acetylneuraminic acid portion of the molecule, but was notshown by other sialic acid derivatives such as ovine mucoid or a ganglioside-like substance from horse erythrocytes.'8and neurotoxicity81 in certain influenza viruses. The viruses contain aneuraminidase and the inhibitions have been ascribed to gangliosidesthemselves 80ps1 and to associated neuraminic acid derivative^.'^ Certainganglioside preparations contain neuraminic acid residues not released byneuraminidase and these preparations do not inhibit hzemagglutination butstill fix tetanus toxin in proportion to their neuraminic acid content.83Characterisation of the gangziosides.Neuraminic acid, the subject of arecent Report,= was recognised and named in 1941 as a distinctive con-stituent of a group of cerebral lipids which also contained fatty acids (mainlystearic), sphingosine, and g a l a c t ~ s e . ~ ~ These were subsequently namedgangliosides 86 and prepared (Method a) from chloroform-methanol extractsof cerebral tissue from which phosphorus-containing compounds wereremoved by cadmium salts and cerebrosides by extraction with aqueousacetone ; purification proceeded through lead salts, adsorption on aluminafrom a solution made in hot pyridine, and precipitation from hot glacialacetic acid. The product yielded 21-22y0 of a chromogen, in currentnomenclature 82,84 N-acetylneuraminic acid, which was obtained as itsmethyl glycoside. Galactosamine 87 was also found to be part of the ganglio-side molecule.It was at first suggested that normal brain contained only about O.lyoof its fresh weight of ganglioside and that this increased to about 1% incertain lipidoses.m By a simple chloroform-methanol (2 : 1) extraction ofbrain, and partition dialysis (Method b) a distinctive glycolipid was foundto constitute 0.7y0 of normal cerebral tissue and named ~ t r a n d i n , ~ ~ but itwas subsequently found to contain some 23% of N-acetylneuraminic acidin addition to each of the constituents already recognised in the gangliosides;peptides were also present.Peptides were not present in material madeby other methods 91 including that extracted from acetone-dried cerebralMaterial in ganglioside preparations inhibits hzemagglutination 79*c 8 IV.E. van Heyningen and P. Miller, J . Gen. Microbiol., 1961, 24, 107.79 A. Rosenberg, C. Howe, and E. Chargaff, NatNre, 1956, 177, 234.8o S. Bogoch, Virology, 1957, 4, 458.S. Bogoch, P. Lynch, and A. S. Levine, Virology, 1959, 7, 161.82 A. Gottschalk, " The Chemistry and Biology of Sialic Acid and Related Sub-stances," Cambridge, Univ. Press, 1960.*3 A. W. Bernheimer and W. E. van Heyningen, J . Gen. Microbiol., 1961, 24, 121.W. J. Whelan, Ann. Re$orts, 1957, 54, 319.x3 E. Klenk, 2. physiol. Chem., 1941, 268, 50.86 E. Klenk, 2. physiol. Chem., 1942, 273, 76.87 G. Blix, L. Svennerholm, and I. Werner, Acta Chem. Scand., 1950, 4, 717; E.8 8 E. Klenk, Proc.1st Internat. Neurochem. Symp., 1955, p. 397.8g J. Folch, S. Arsove, and J. A. Meath, J . Biol. Chem., 1951, 191, 819.Klenk, 2. physiol. Chem., 1951, 288, 216,H. Daun, Diss., Cologne, 1952; J. Folch, J. A. Meath, and S. Bogoch, Fed. Proc.,L. Svennerholm, Acta Chem. Scand., 1956, 10, 694.1956, 15, 254378 BIOLOGICAL CHEMISTRY.tissue by hot chloroform-methanol (1 : 2) (Method c).~~ Material preparedby Method b has also been termed ga " brain mucolipid " which does notappear an adequately specific description of the major group of cerebralsialmucolipids, for which it is suggested that the name " gangliosides " beretained; subsequent ganglioside preparations, based on Method a, havegiven yields approaching those from Method b. Brain also contains otheracidic glycolipids and protein-bound derivatives of neuraminic acid notsoluble in lipid solvents; 91 also further ganglioside-like extractives areyielded to chloroform-methanol (2 : 1) in presence of the antitrypanosomaldrug ~ u r a m i n .~ ~Properties and structure of gangliosides. The distinctive oil-watersolubility of ganglioside mixtures enables crude preparations to be maderelatively easily and gives specificity to methods for their determinationbased on measurement of N-acetylneuraminic acid.66s94* 95 Althoughextremely water-soluble after extraction, gangliosides appear to be in firmassociation in the tissue with other materials and are not extracted by avariety of aqueous reagents. After extraction, e.g., by Method b (above)they are easily washed out of chloroform-methanol by dilute aqueous saltsolution; 95~96 they are not easily diffusible 86*89 and dialysis of the aqueoussolution, followed by evaporation, gives a preparation containing 26-30%of N-acetylneuraminic acid, representing an enrichment of about 300-foldover the original cerebral content.Ultracentrifugal measurement of molecular weight in aqueous solutionhas suggested values of 180,000-250,000 or more for material prepared byMethod b.89992*97 Method a yielded material having M 1500 in dimethyl-formamide 98 and as this material also was non-diffusible in aqueous solu-tion86 a molecular weight of this order appears likely to represent theganglioside molecule ; the larger values will represent colloidal aggregates 91or mi~elles.~s Preparations b were salts of an acid of equiv.wt. 1200-1500; 8 6 ~ 8 ~ they contained little sulphur or phosphorus and so were distinctfrom sulphatides and phosphatides. N-Acetylneuraminic acid, the onlyacidic moiety, was split from the molecule by mild acid-hydrolysis ; 85991397598in the early stages of hydrolysis it is the only diffusible product and hastherefore been considered to be a terminal grouping. Further hydrolysisof the residue yields also galactose and galactosamine and leaves acerebroside ; the quantities involved led to tentative structures con-taining 2 cerebroside, 1-2 hexosamine, 2-3 hexose, and 2-3 neuraminicacid re~idues.8~9~~ Fractionation of gangliosides (Method c) on cellulosecolumns,99 ion-exchange resins,g1 or silicic acid has, however, yielded92 A.Rosenberg and E. Chargaff, J . Bid. Chem., 1958, 232, 1031.93 S. Balakrishnan and H. McIlwain, unpublished work.94 L. Svennerholm, Acta SOC. Med. Uppsalla, 1957, 62, 1; Acta Chem. Scand., 1958,95 C. Long and D. A. Staples, Biocbzem. J., 1959, 73, 385.g6 J. Folch, M. Lees, and G. H. Sloane-Stanley, J . Biol. Chem., 1957, 226, 497.97 S. Bogoch, Biochem. J., 1958, 68, 319.9s E. Klenk and W. Gielen, 2. Physiol. Chenz., 1960, 319, 283; A. Rosenberg andE. Chargaff, Bioclzim. Biophys. Acta, 1960, 42, 357; J. D. Karkas and E. Chargaff,Biochinz. Biophys. Acta, 1960, 42, 359.s9 I>. Svennerholm, Acta Chem. Scand., 1954, 8, 1108; R. Kuhn, Proc. 4th Internat.Congr. Biochem., 1959, 1, 69.12, 547WHITTAM : CHEMICAL ASPECTS OF ACTIVE TRANSPORT.379material of simpler molar ratios, for one of which was proposed thesequence : looN- Acetylneuraminic acid-N-acetylgalactosamine-galactose-glucose-sphingosine-fatty acidFrom products of methylation (which proved difficult and was achievedto the extent of 86%) and hydrolysis, provisional structural formulze havebeen pr0posed,~8 one of which contains the above sequence. A secondmaterial without hexosamine was considered to be present; others 78 haveseparated two ganglioside components both containing hexosamine, butwith varying content of N-acetylneuraminic acid. Values quoted above forN-acetylneuraminic acid in ganglioside preparations obtained by Method 6are higher than required by the preceding formula, implying the presence ofa further constituent.The separation of 8 or 9 ganglioside fractions by apartition methodlol appears likely to be related to micelle formation inaqueous solution ; the material contained peptides which, it was concluded,were an essential part of the molecule. However, the material was preparedby Method b and lipophilic proteins and peptides are extractable fromcerebral tissue in conditions similar to Method b but to a smaller extentonly in those of Method c.lo2 One protein associated with ganglioside(Method b) contained 35% of argininelo3 and firm associations betweengangliosides and arginine-rich histones have been o b s e r ~ e d . ~ ~ ~ ~ ~ J ~ Manyaspects of ganglioside chemistry remain to be solved, and at present theformulation above may be regarded as a probable structure of one majorcomponent of the ganglioside mixture.Ion movements, reviewed in this and the following section,constitute very much the centre of neurochemistry. Their interpretationis now the subject of many hypotheses; one, concerning the active move-ments of Na+ and Kf, is based on evidence suggesting that the Na+- andK+-activated adenosine triphosphatase acts in association with neuraminicacid derivatives in utilising phosphate-bond energy for extrusion of Na+.lo5While not attempting appraisal here, it is to be noted that several suchhypotheses have reached points a t which purely chemical studies can makemajor contributions ; when, for example, stereochemical aspects of ganglio-side structure, or the kinetics of postulated metabolic changes, can becomccritical in choice of mechanism.Comment.H.McI.4. CHEMICAL ASPECTS OF ACTIVE TRANSPORTIN view of the absence of previous Reports on active transport the presentarticle will be devoted mainly to an outline of the problem and to the trans-port of alkali metals. A description of cation movements in certain cellsand a discussion of recent chemical investigations will be made. General100 L. Svennerholm, Nature, 1956, 1'97, 824.101 H. L. MeItzer, J. Bid. Chem., 1958, 233, 327.102 L. L. Uzman and M. K. Rumley, Arch. Biochem. Biophys., 1960, 89, 13.1°3 F. N. Le Baron and J . Folch, PhysioZ. Rev., 1957, 37, 539.In4 A. F. Harris and A. Saifer, J.Neurochem., 1960, 5, 218, 383.10s H. McIlwain, Res. Publ. Assoc. Res. Nerv. Ment. Dis., 1960, 40, in the press380 BIOLOGICAL CHEMISTRY.publications on the subject include a monograph,l reviews,2 and proceedingsof symposia; and related reviews have appeared on the transport of sugarsJ4Definition.-The potassium concentration in almost all the living cellsthat have been studied is higher than in the fluid normally surroundingthem, and in most cells the sodium concentration is lower than that outside.’These concentration gradients are not maintained by non-diffusible anionslocated on one side of inert semi-permeable membranes, or by impermeablemembranes, because a leakage of potassium and an uptake of sodium occurswhen the cell metabolism is inhibited.Radioactive tracers of these metalsalso reach approximate isotopic equilibrium between intracellular and extra-cellular fluids in vivo under conditions such that the concentration gradientsremain constant.8 Further, potassium and sodium ions may be selectivelytransported into and out of cells against concentration and electrical poten-tial gradients. These facts, together with similar facts about the transport,across membranes, of sugars, amino-acids, and carboxylic acids, raise theproblem of “ active transport.”It is worth stating first that the maintenance of concentration gradientsof alkali-metal ions across cell membranes generally is closely related to theproblems of secretion and absorption. Secretion involves the elaborationfrom one side of cells of material that is either absent or in low concentrationon the other side, and absorption implies the transport of material acrosscells; in both cases, cells are joined together as an epithelium which separatesthe fluid on each side of it.Whilst trans-cellular flow of material is there-fore the property of certain epithelia only, active transport across cellmembranes appears to be a property of all cells whether they are bacteriaor from plants lo or animals.l Secretion and absorption may be regarded asfats,6b and amino-acids61 E. J. Harris, “Transport and Accumulation in Biological Systems,” 2nd ed.,Butterworth’s Scientific Publications, London, 1960. * A. L. Hodgkin, Proc. Roy. Soc., 1958, B, 148, 1; I. M. Glynn, Internat.Rev. Cytol.,1959, 8, 449; A. Leaf, Ann. New York Acad. Sci., 1959, 72, 396; F. A. Fuhrman, Ann.Rev. Physiol., 1959, 21, 19; ,p. M. Shanes, Pharm. Rev., 1959, 10, 59.The Method of Isotopic Tracers Applied to the Study ofActive Ion Transport,” Pergamon, London, 19$?; Q. R. Murphy (editor), “ MetabolicAspects of Transport Across Cell Membranes, Univ. of Wisconsin Press, Madison,U.S.A., 1957; G. E. W. Wolstenholme and C. M. O’Conner (editors), Ciba FoundationStudy Group No, 5, “ Regulation of the Inorganic Ion %ntent of Cells,” J. and A.Churchill Ltd., London, 1960; A. M. Shanes (editor), Electrolytes in BiologicalSystems,’’ Amer. Physiol. SOC., Washington, D.C., 1955.4 W. Wilbrandt, J . Pharm. Pharmacol., 1959, 11, 65; C. R. Park, D. Reinwein,M.J. Henderson, E. Cadenas, and H. E. Morgan, Amer. J . Med., 1959, 26, 674; R. B.Fisher, Brit. Med. BUZZ., 1960, 16, 224; P. J. Randle and F. G. Young, ibid., p. 23’7;F. Bowyer, Internat. Rev. Cytol., 1957, 6, 469.5 (a) J. R. Robinson, Physiol. Rev., 1960, 40, 112; R. P. Durbin, P. F. Cunan,and A. K. Solomon, Adv. Biol. Med. Physics, 1958, 6, 1; (b) A. C. Frazer, Brit.Med. Bull., 1958, 14, 212; D. S. Fredrickson and R. S. Gordon, Physiol. Rev., 1958,88, 585.Biochemistry,” Academic Press, London, Vol. 11, 1960, p. 403.23, 175; H. A. Krebs, R. Whittam, and R. Hems, Biochem. J., 1957, 66, 63.Biol. Rev. Camb. Phil. Soc., 1959, 84, 169; R. N. Robertson, ibid., 1960, 85, 231.8 J. Coursaget (editor),6 H. N. Christensen, Adv. Protein Chem., in the press.7 F.Brown and W. D. Stein in M. Florkin and H. S. Mason’s (editors), ‘I Comparative8 A. Krogh, Proc. Roy. SOG., 1946, B, 133, 140.0 P. Mitchell, Ann. Rev. Microbiol., 1959, 18, 407; A. Rothstein, Bact. Rev., 1959,10 E. A. C. McRobbie and J. Dainty, J. Gen. Physiol., 1958, 42, 335; J. F. SutcliffeWHITTAM : CHEMICAL ASPECTS OF ACTIVE TRANSPORT. 381specialised aspects of active transport in which the transport is predomin-antly in one direction across a layer of cells.described by the forces of diffusion, the membrane potential, or a Donnanequilibrium and, instead, depend on chemical reactions intimately connectedwith metabolism. A rigorous definition is a movement occurring againstboth a concentration and an electrical potential (or electrochemical) gradientand hence, more generally, from a phase of low to one of high electrochemicalpotential.ll.12 The direction of active movements is, therefore, opposite tothat which would cause the cell to approach thermodynamic equilibriumwith its environment.This means that energy must be provided, and theonly possible source is metabolism. The fundamental problems of activetransport are the chemical nature of the mechanism responsible for theseion movements and the way in which the transport is linked to metabolism.Kinetic and metabolic aspects of active cation transport will be consideredfirst, because these have established the facts and characterised the process.The basic theories will then be discussed.Kinetics.-Very many data (referred to as flux data) on the rates ofmigration of sodium and potassium ions across membranes have beenobtained with 24Na and 42K under conditions such that a steady state wasmaintained.(For discussions of the steady state in biology, see ref. 13.)Net changes in concentrations have also been measured by flame-photo-metric analysis; both kinds of data show some common features in the move-ments of sodium and potassium ions that occur across membranes of differentkinds of cells. The most precise information has been obtained with muscleand nerve fibres, in which the membrane potential can be measured, andwith red blood cells, in which the membrane potential can be regarded asboth small and constant. Although the latter has never been measured,the distribution of chloride between the inside and the outside of human redcells depends primarily l4 on pH and appears to be determined by a Donnanequilibrium created mainly by hzemoglobin; it is reasonable to suppose thatthe potential difference is similarly dependent.Essentially, the experimentshave been concerned with the measurement of the rates of movement ofions into and out of cells and with the effect on these movements of varyingthe composition of the saline medium in which the cells are immersed.After it had been established in the early experiments with tracers,about 1941, that cell membranes generally were permeable to both sodiumand potassium i ~ n s , ~ J ~ two concepts arose to explain the uneven distributionof these ions across the membrane.First, there is the membrane hypothesis,which supposes that the intracellular ions are almost completely freelyionised and that the selectivity of cells towards sodium and potassium arisesfrom chemical forces, by which they are moved across the membranes ofActive transport may be said to occur when ion movements cannot be-l1 T. Rosenberg and W. Wilbrandt, Internat. Rev. CytoZ., 1952, 1, 65; I. M. Glynn,l2 H. H. Ussing, Physiol. Rev., 1949, 29, 127; Nature, 1947, 160, 262,l3 E. J . Conway, Physiol. Rev., 1957, 37, 84; A. von Bertalanffy, Science, 1950, 111,l4 E. J. Harris and M. Maizels, J. PhysioZ., 1952, 118, 40.l5 W. 0. Fenn, T. R. Noonan, L. G. Mullins, and L. Haege, Amer. J. Physiol., 1941,Prop. Biophysics Biophys.Cham., 1957, 8, 241.23.135, 149; L. A. Hahn, G. C. Hevesy, and 0. H. Rebbe, Biochem. J., 1939, SS, 1549382 BIOLOGICAL CHEMISTRY.living cells, metabolic energy being used to accumulate potassium and toexpel sodium. A substance in the membrane is thought to combine speci-fically with the ion to be actively transported and the complex then diffusesacross the membrane.16-18 By liberating the ion at the opposite face ofthe membrane, a concentration gradient for the complex can be set up inthe direction of transport. Mathematical equations describing the kineticsof this system have been derived but almost nothing is known about thechemical nature of the carrier molecules. Secondly, there is the view thatthe high potassium concentration inside cells is due to the intracellular bind-ing of this ion in preference to sodium.The membrane hyj$othesis. The evidence for the membrane hypothesisis: (1) The interior of muscle and nerve fibres is at a uniform potentialabout 50-95 mv negative with respect to the outside, and the potentialdrop apparently occurs abruptly over a depth of less than 1 p when themicroelectrode impales the membrane.lg (2) Intracellular 42K in cuttlefishnerve axons and in frog muscle fibres 21 moves down a longitudinal voltagegradient with a mobility similar to that of potassium ions in potassiumchloride solution.Further, osmotic balance suggests that almost all theinternal potassium ions must contribute towards the intracellular osmoticpressure.22 (3) The time course of the exchange of =Na and 42K betweenthe inside and the outside of single muscle 23 and nerve fibres 24 follows simpleexponential laws for first-order processes, as is to be expected for a two-phase system in which the membrane is the main barrier to diffusion. Asmall amount of sodium less mobile than the bulk of the sodium in the fibreshas been reported,25 but it is probably bound in connective tissue at theends of the muscle.The general applicability of first-order kinetics to theexchanges of ions across cell membranes has, however, been doubted 1p26on the grounds that diffusion within cells is rate-limiting as well as thetransfer across the membrane. (4) The membrane resting potential agreeswell with that predicted by the Nernst equationRT activity of potassium insideP activity of potassium outside E=-lnwhere E is the membrane potential, and RT and P have their usual mean-i n g ~ .~ ' Concentrations have been used in the equation instead of activities,but it is perhaps reasonable to assume that the activity coefficients are closeto unity. The dependence of the potential difference of frog striated16 J, F. Danielli, Symp. SOC. Ex@. Biol., 1954, 8, 502.17 A. L. Hodgkin and R. D. Keynes, J. Physiol., 1955, 128, 28.T. I. Shaw, J. Physiol., 1955, 129, 464.l9 A. L. Hodgkin, Biol. Rev. Camb. Phil. SOC., 1951, 26, 339.20 A. L. Hodgkin and R. D. Keynes, J. Physiol., 1953, 119, 513.E. J. Harris, J. Physiol., 1954, 124, 248.22 E. J . Conway and J. I. McCormack, J. Physiol., 1953, 120, 1.23 A.L. Hodgkin and P. Horowicz, J , Physiol., 1959, 145, 405.24 R. D. Keynes, J. Physiol., 1951, 114, 119; A. M. Shanes and M. D. Bermann,25 E. J . Harris and H. B. Steinbach, J. Physiol., 1956, 133, 385.26 E. J. Harris, J. Gen. Physiol., 1957, 41, 169; C. Edwards and E. J . Harris, J.27 G. Ling and R. W. Gerard, Nature, 1950, 165, 113.J . Gen. Physiol., 1955, 39, 279.Physiol., 1957, 135, 667WHITTAM : CHEMICAL ASPECTS OF ACTIVE TRANSPORT. 383muscle on the distribution of potassium at equilibrium holds for a variationboth of internal and of external potassium.28 When the external potassiumconcentration was rapidly raised, the resulting depolarisation was fasterthan the repolarisation found when a high external potassium concen-tration was rapidly 1 0 w e r e d .~ ~ ~ ~ ~ Chemical estimations show that thesechanges are correlated with a movement of potassium chloride that is fasterinwards that outwards.30 These observations recall the rectification effectin the muscle membrane that was in the same d i r e ~ t i o n . ~ ~ The above factsthrow doubt on the alternative hypothesis that the high internal potassiumconcentration is due to binding to (unknown) compounds with a high affinityfor potassium,32 but discussion on this controversial matter continue^.^^^^^That the membrane is the site of thediscrimination between sodium and potassium is suggested by the linkagethat has been observed between part of the outward movement of sodiumwith part of the inward movement of potassium.Whilst the outwardmovement of sodium is clearly active, for it is against both a concentrationand an electrical gradient, the inward movement of potassium might bepassive and occur to maintain electroneutrality or as a result of the mem-brane potential. Further, it would not be evidence of a linkage to showthat metabolic inhibitors cause passive movements of sodium and potassiumin opposite directions, for this would be expected even if the potassiummovements were consequential to the sodium movements. However, theextrusion of sodium from frog muscle requires the presence of potassium inthe saline medium,35 and a similar reduction in sodium efflux after removalof potassium from the outside solution has been shown in Sepia giant nerveaxons l7 and in horse l8 and human 36937 red cells.The maintenance of thepotassium concentration in brain-cortex slices is also partly dependent onthe presence of sodium in the medium.38 The effect of the externalpotassium concentration on the outward movement of sodium from cells isdifficult to explain other than by a chemical reaction in the membrane thatsimultaneously causes a movement of sodium outwards and of potassiuminwards.To test whether part of the sodium efflux from frog muscle was dependentalso on the presence of sodium in the outside solution, a detailed study ofthe efflux of sodium was made when lithium and choline were substitutedfor sodium in the external solution. A one-to-one exchange of internalsodium for external sodium would not cause a net movement and could besimilar to the exchange of ions between a cation-exchange resin and aInter-relation of ion movememk.28 R. H.Adrian, J. Physiol., 1956, 133, 631.2y A. L. Hodgkin and P. Horowicz, J. Physiol., 1959, 148, 127.30 R. H. Adrian, J. Physiol., 1960, 151, 154.31 B. Katz, Arch. Sci. physiol., 1949, 3, 285.32 G. Ling, J. Gen. Physiol., 1960, 43, supplement, 149; S. E. Simon, Nntuve, 1959,L. M. Chailakhian, Biophysics, 1959, 4, 1; A. S. Troskin, ibid., 1960, 5, 104,34 E. J. Conway, J . Gen. Physiol. , 1960,43, supplement, 17.35 R. D. Keynes, Proc. Roy. SOC., 1954, B, 142, 359.36 E. J. Harris and M. Maizels, J. Physiol., 1951, 113, 506.37 I. M. Glynn, J. Physiol., 1956, 134, 278.38 H. M. Pappius, M. Rosenfeld, D. hlcL.Johnson, and K. A. C . Elliott, Canad.184, 1978.J . Biochem. Physiol., 1958, 36, 217384 BIOLOGICAL CHEMISTRY.solution, and for cases where this kind of exchange is apparently mediatedby a carrier in the membrane the term exchange diffusion has been sug-gested.12 It was shown by Keynes and Swan39 that the sodium efflux wasreversibly reduced by about 50% in the absence of external sodium, andthe suggestion of exchange diffusion thus received experimental support.The effect of removing external sodium was found to add to that of removingexternal potassium, which had earlier been shown in itself to reduce sodiumefflux.% The outward movement of tracer sodium from frog muscle istherefore coupled partly to an inward movement of sodium and partly to aninward movement of potassium.A linkage between movements of sodiumand of potassium has also been found in rat skeletal muscle, in which thesodium efflux was affected by the concentrations of both sodium and potas-sium in the bathing solution; the potassium uptake was also facilitated bythe presence of sodium.40 Part of the sodium efflux from human red cellscan also be ascribed to exchange diffusion, as it persists in the absence ofglucose and of external potassium.37 Kinetic studies with both human redcells and striated muscle therefore show that the movements of sodium andpotassium across membranes are partly coupled in a way which does notseem to be a simple requirement of maintaining electroneutrality.Metabolic Aspects.-There has been much interest in the effects of meta-bolism on the distribution and rates of movements of ions across mem-branes, because a knowledge of the way in which metabolism is linked toactive transport is almost certain to throw light on the chemistry of thetransport process.Tissues and cells appear to fall into three groups asregards their dependence on metabolism for active transport. First, thereare mammalian red cells which do not respire very markedly and dependon glycolysis for energy for active transport. Then there are cells whichderive energy from either respiration or glycolysis, depending on whetherthey are incubated aerobically or anaerobically. These cells exhibit a highPasteur effect in being able to adapt metabolically to the deprivation ofoxygen by increasing their rate of lactic acid production.This metabolicphenomenon is characteristic of fetal tissue and of rapidly dividing cells,such as those in cancerous tissues and some epithelia.a A third kind of celldepends almost entirely on respiration because the rate of glycolysis is toolow anaerobically to provide sufficient energy. The only common featuresin the various kinds of dependence on metabolism are the synthesis of ATPfrom ADP, and the oxidation and reduction of co-enzyme 1 (DPN) ; evidencewill be noted later which suggests that a supply of ATP is the requirementfrom metabolism for active transport.Human red blood cells were among the firstliving cells to be shown to require energy from metabolism for the mainten-ance of concentration gradients of alkali metals, as distinct from processesof absorption and secretion which have long been known to require metabolicenergy.During cold storage of blood at 4", the red cells lose potassium d2Dependence on glycolysis.39 R. D. Keynes and R. C. Swan, J . Physiol., 1969, 147, 591.40 H. McLennan, Biochim. Biophys. Actu, 1957, 24, 333.41 0. Warburg, Science, 1956, 123, 309.42 M. Maizels and N. Whittaker, Lancet, 1940, I, 590; C. B. B. Downman, J. 0.Oliver, and I. M. Young, Brit. Med. J., 1940, I, 559WHITTAM CHEMICAL ASPECTS OF ACTIVE TRANSPORT. 385which can be regained when the temperature is raised to 37".43944 There-accumulation of potassium requires glucose and is blocked by low con-centrations of fluoride and iodoacetate which inhibit g l y c ~ l y s i s .~ , ~ ~ Sodiumleaks into cells at 4", but is expelled again when they are warmed for somehours after cold storage, and glucose is also required.44 Active accumulationof potassium occurs also in fermenting yeast with considerable specificity,hydrogen ions being liberated into the medium in exchange for potassium; 46sodium can also be expelled actively from yeast.47 Inhibitors of respirationsuch as malonate, azide, cyanide, and fluoroacetate have no effect on theactive movements in red cells.48 Similar results have been found with redcells of other mammals, such as rabbit, horse, and dogg9 The normalactive transport of sodium and potassium in human red cells depends on afirm union of calcium in the membrane, because once this bond is brokenthe cells become highly permeable to electrolyte^.^^ The effect of high con-centrations of fluoride in rendering the cells permeable to ions 51 is probablydue to removal of calcium from the membrane.An ability to transport sodium and potassium ions against concentrationgradients both aerobically and anaerobically has been demonstrated in slicesof the cortex cut from kidneys of new-born rabbits and rats.52 Duringanaerobic incubation in a medium 5 mM in potassium, the tissue retainedmore potassium (about 65 m.-equiv. per kg.of tissue) than it did whenglycolysis was inhibited with iodoacetate (about 25 mmole per kg. wet wt.).The loss of potassium on inhibition of both respiration and glycolysis wasbalanced by a gain of sodium.Immature young animals of some speciesare able to survive anoxia for appreciable periods (about 30 and theability of kidney slices to prevent a loss of potassium is one aspect of theresistance to anoxia which is not shown by the same tissue from adultanimals of the same species. Slices of seminal vesicle mucosa of guinea pigscan also transport ions actively during anaerobic, as well as during aerobic,i n c ~ b a t i o n . ~ ~ Ascites tumour cells manifest a marked Pasteur effort andare able to expel sodium actively provided that either respiration or glyco-lysis is allowed. Thus, no fall in sodium efflux occurred when respirationwas depressed with cyanide, but further addition of iodoacetate, to inhibitglycolysis also, did cause a fall in the efflux.55 The potassium influx intofresh duck red cells, which are nucleated and can both respire and glycolyse,43 J.E. Harris, J . Biol. Chem., 1941, 141, 579.44 M. Maizels, J . Physiol., 1949, 108, 247.45 T. S. Danowski, J . Biol. Chem., 1941, 139, 693.46 E. J. Conway and E. O'Malley, Biochem. J . , 1946, 40, 59; A. Rothstein and L. H.Enns, J . Cell. Compt. Physiol., 1946, 28, 231.47 E. J. Conway and D. Hingerty, Biochem. J., 1953, 55, 455.4* M. Maizels, J . Physiol., 1951, 112, 59.49 M. Maizels, Symp. SOC. Ex?. Biol., 1954, 8, 202; H. S. Frazier, A. Sicular, andA. K. Solomon, J . Gen. Physiol., 1954, 87, 631.50 V. Bolingbroke and M. Maizels, J . Physiol., 1959, 149, 563.51 R, E. Eckel, Amer.J . Physiol,, 1954, 179, 632.52 R. Whittam, J . Physiol., 1960, 153, 358.53 J. F. Fazekas, F. A. D. Alexander, and H. E. Himwich, Anzer. J . Physiol., 1941,54 H. J. Breuer and R. Whittam, J . Physiol., 1957, 181, 213; R. Whittam and55 M. Maizels, M. Remington, and R. Truscoe, J . Physiol., 1958, 140, 80.134, 281.H. J. Breuer, Biochem. J., 1959, 72, 638.REP.-VOL. LVII 386 BIOLOGICAL CHEMISTRY.appears to be greater under anaerobic conditions that aerobically, althoughthe effect depends on the external potassium concentrati~n.~~ Anotherexample of active transport independent of respiration is potassium uptakeby rabbit polymorphonuclear leucocytes, in which the rate of glycolysis andalso the rate of potassium uptake are increased when the respiration isinhibited by cyanide.In these cells, there seem to be separate mechanismsfor the uptake of potassium and the extrusion of sodium, but both theseactive transfers, which occur after a period of storage a t 4", depend onglycolysis rather than re~piration.~' A net trans-cellular movement ofsodium chloride across anaerobic frog skin separating two pools of the samefluid suggests that this tissue is able to transport sodium anaerobically,although at a much lower rate than that is found aer~bically.~* The trans-port was measured as the current flow across the short-circuited skin, which,under aerobic conditions, has been shown to arise from the active transportof sodium.59Dependence on respiration. By far the largest group of tissues is thatrequiring oxygen for active transport.The study of the effects of a varietyof conditions (cooling, cyanide, anoxia) causing either inhibition of respir-ation or (2,4-dinitrophenol) an uncoupling of the supply of ATP fromrespiration has shown that the following tissues require the normal respir-atory activity and concomitant formation of ATP: brain and kidney 62cortex slices from adult guinea pigs and rabbits, retina of the oxJ6* ratdiaphragm 63 and skeletal muscle,64 and giant nerve axons of squid^.^^^^^Inhibition of respiration in this group of tissues causes a net gain of sodiumand a net loss of potassium, and these changes can usually be reversed byrestoring the respiration. It is certain that sodium is actively expelled fromthe cells, but in tissue slices the potential difference across the membranes isnot accurately known, although in the cells that have been studied, the insideis negative to the outside.66 It is therefore difficult to decide whetherpotassium is actively transported inwards or whether it is attracted inwardsby the internal negative electrical potential.The inhibition of metabolismmay, therefore, cause a leakage of potassium because of an inhibition of anactive transport mechanism for potassium, or as a secondary effect becauseanother cation must move in an opposite direction to preserve electro-neutrality when a net entry of sodium occurs. These possibilities cannotbe distinguished until the membrane potential is known.58 D. C. Tosteson and J. S. Robertson, J .Cell. Comfit. Physiol., 1956, 47, 147.57 P. Elsbach and I. L. Schwartz, J . Gen. Physiol., 1959, 42, 883.58 A. Leaf and A. Renshaw, Biochem. J., 1957, 65, 90.59 H. H. Ussing and K. Zerahn, Ada Physiol. Scand., 1951, 23, 110.60 C. Terner, L. V. Eggleston, and H. A. Krebs, Biochem. J., 1949, 47, 139.61 H. A. Pappius and K. A. C. Elliott, Canad. J . Biochem. Physiol., 1956, 34, 1053.62 H. A. Krebs, L. V. Eggleston, and C. Terner, Biochem. J., 1951, 48, 530; G. H.Mudge, Amer. J . Physiol., 1951, 165, 113; R. Whittam and R. E. Davies, Biochem. J.,1953, 55, 880; H. Aebi, Helv. Physiol. Pharmacol. Acta, 1953,11, 96; I. Deyrup, Amer.J . Physiol., 1953, 175, 349.63 R. Creese, Proc. Roy. Soc., 1954, B, 142, 497; E. Calkins, I. M. Taylor, and A.B.Hastings, Amer. J . Physiol., 1954, 177, 211.64 H. McLennan, Biochim. Biophys. Acta, 1956, 22, 30.6.5 A. M. Shares and M. D. Berman, J . Gen. Physiol., 1955, 39, 279.66 C.-L. Li and H. McIlwain, J . Physiol., 1957, 139, 178WHITTAM : CHEMICAL ASPECTS OF ACTIVE TRANSPORT. 387Slices of brain 67~@ and kidney cortex 69 and of liver 70 swell considerablywhen the aerobic metabolism is reduced either by cooling or by the additionof inhibitors at 3 7 O . The swelling is due to an entry of water into thecells G9.71 and, in kidney slices, the water content decreases when optimumconditions for respiration at 37" are restored. The uptake of water istherefore reversible. Although it was held that the prevention of the entryof water into respiring cells may itself require energ~,~2 on the suppositionthat the intracellular osmotic pressure was greater than that outside, thisview is no longer tenable.6" Direct cryoscopic measurements of osmoticpressure have shown that no activity gradient of water exists, whatever thestate of hydration of the ce11s.22p73 Furthermore, to a first approximation,the entry of water into cells in metabolically unfavourable conditions isaccompanied by an entry of sodium chloride, which may be ascribed to afailure of the active transport mechanism for sodium.74 The entry ofsodium is therefore balanced partly by a loss of potassium and partly by anentry of chloride,71 and the net uptake of sodium chloride is in the form ofextracellular fluid.The maintenance of the normal volume of cells may beconsidered to depend upon the active transport mechanism for sodiumwhich can thus be seen to occupy a central position in the control of thewater, chloride, and potassium concentrations of the cells.The results obtained with sartorius muscles from frogs are conflicting.Thus, cyanide did not cause a net loss of potassium from frog muscles whenthey were in a condition close to the state in v ~ v o , ~ ~ nor did it cause a changein sodium efflux from muscles containing a high sodium concentration afterstorage for several hours at 4°.76 Other recent work, however, shows thatcyanide and anoxia inhibit net sodium extrusion by 60% during a periodof incubation after the muscles had been soaked overnight at 0°.77 Themuscle sodium concentration also decreased when 2,4-dinitrophenol wasadded at a concentration that inhibited oxidative phosphorylation. Itshould be noted that the large store of creatine phosphate in striated muscleallows contraction to continue even after poisoning and may also accountfor the apparent insensitivity of sodium extrusion towards inhibitors by asimilar provision of ATP from the operation of creatine phosphokinase.The Redox Pump Theory.-A theory to explain how energy derived frommetabolism may be linked to active movements of cations has been formul-67 J.R. Stern, L. V. Eggleston, R. Hems, and H. A. Krebs, Riochem. J., 1949,68 H. M. Pappius and I<. A. C. Elliott, Caizad. J . Biochem. Physiol., 1956,6s J. R. Robinson, PYOC. Roy.SOL, 1950, B, 137, 378.'O J. R. Robinson, PYOC. Roy. Soc., 1952, B, 140, 135; K. D. Heckmann and D. S.71 R. Whittam, J. Physiol., 1956, 131, 542,7 2 J. R. Robinson, Biol. Rev. Camb. Phil. SOC., 1953, 28, 158.'3 J. W. T. Appelboom, W. A. Brodsky, W. S. Tuttle, and I. Diamond, J . Gen.Physiol., 1958,41, 1153; W. A. Brodksy, J. W. Appleboom, W. H. Dennis, W. S. Rehm,J. W. Miley, and I. Diamond, ibid., 1956, 40, 183; R. H. MaHy and A. Leaf, ibid.,1959, 42, 1257,44,410.34, 1007.Parsons, Biochim. Biophys. Acta, 1959, 36, 203, 213.74 A. Leaf, Biochem. J., 1956, 62, 241.I.' R. D. Keynes and G. W. Maisel, PYOC. Roy. SO~., 1954, B, 142, 383.i 6 H. S. Frazier and R. D. Keynes, J . Physiol., 1959, 148, 362.7 7 M. J. Carey, E. J. Conway, and R. P.Kernan, J . PhysioE., 1959, la, 61.- 388 BIOLOGICAL CHEMISTRY.ated by C o n ~ a y , ~ , ~ ~ although Lund 79 first introduced the concept of oxido-reduction as sources of bioelectric phenomena in cells. A redox theory foractive accumulation of anions by plants has been formulated; a similarconcept to account for the secretion of hydrochloric acid was proposed,S1and later modified to account for high rates of secretion.82 The crux of thehypothesis is that the flow of electrons through the reduction-oxidationchain of reactions of the cytochrome system liberates hydrogen ions, fromthe hydrogen of metabolites, at a site in the cell different from that wherethe electrons are accepted by oxygen to form hydroxyl ions. The reactionsdepend on the oxidation and reduction of iron:4FeS+ + 4H = 4Fea+ + 4H+4Fe2+ + 2H,O + 0, = 4Fes+ + 40H-2H,O + 0, = 4H+ + 4 0 H -The theory suggests that hydrogen ions are either secreted or are free toexchange with other cations across the cell membrane, instead of combiningwith hydroxyl ions to form water. The high specificity of the transportmechanism presents a difficulty, which is overcome, however, by postulatingthat a membrane carrier is directly connected with the iron pigments in thecytochrome chain.A recent account of this theory stresses the importanceof the size of the hydrated cations that may exchange for hydrogen ions.%It follows that, if sodium and potassium ions are transported as a secondaryexchange with hydrogen ions, then four is the maximum number of ions thatcould be moved per molecule of oxygen reduced.A critical test of the theory has been made with frog skin where the sodiumions actively transported across the short-circuited epithelium were shownto range from 2-13 per molecule of oxygen consumed.83 The sodium fluxacross the skin accounts for the current flowing when identical solutions onopposite sides of the skin are short-circuited to abolish the potential differ-ence that normally exists.59 Similar results have been obtained with toadbladder,s4 and appear to invalidate for these tissues a simple mechanism ofactive transport causally linked to the oxidation and reduction of iron-containing compounds in the cell.The question is still open as regards frogsartorius muscle for, as described above, similar experiments have givenconflicting results.76$ 77Role of ATP.-An alternative to the redox pump as the link betweenmetabolism and ion transport is a mechanism dependent on a supply of ATP,which is synthesised during both respiration and glycolysis.This possibilityhas recently received much attention as it might apply generally to anaerobic,as well as to aerobic, active transport.Two kinds of experiment have been made with human red Red cells.78 E. J. Conway, Internat. Rev. Cytol., 1953, 2, 419; 1955, 4, 377.79 E. J. Lund, J . Exptl. Zool., 1928, 51, 265.80 H. Lundeggrdh, Synzp. SOC. exp. Biol., 1954, 8, 262; Nature, 1939, 148, 203.111 E. E. Crane, R. E. Davies, and N. M. Longmuir, Biochem. J., 1948, a, 321.82 R.E. Davies and A. G. Ogston, Biochem. J., 1950, 46, 324.83 A. Leaf and A. Renshaw, Biochem. J.. 1957, 65, 82; K. Zerahn, Acta Physiol.84 A. Leaf, L. B. Page, and J. Anderson, J . Biol. Chem., 1959, 234, 1625; A. Leaf,Scand., 1956, 38, 306.J. Anderson, and L. B. Page, J. Gem Physiol., 1968, 41, 667WHITTAM : CHEMICAL ASPECTS OF ACTIVE TRANSPORT. 389cells to find out whether the active movements of sodium and potassiumcan occur in the absence of metabolism provided ATP is available. Oneapproach was to measure the potassium influx into cells deprived of glucosewhen they contained different amounts of endogenous ATP, to see whetherfalling concentrations of ATP were associated with reduced rates of potassiuminflux. After allowance for some production of ATP from ADP owing tothe metabolism of endogenous phosphorylated intermediates, it was shownthat the potassium influx, measured at hourly intervals, was linearly relatedto the mount of ATP hydrolysed in the same time.85 A similar result hasalso been quoted in an abstract.86 Studies of net changes in potassium con-centration also show that the prevention of a loss of potassium is correlatedwith the hydrolysis and re-synthesis of ATP.@p8' The falI in ATP concen-tration and potassium influx caused by metabolic inhibitors is not in itselfproof that the active transport depends on ATP, because the inhibitorscould affect the transport and metabolic processes separately without alink via ATP existing between them.The correlation between potassiuminflux and the rate of hydrolysis of ATP suggested, however, that ATP maybe a link between metabolism and active transport.A more direct approach has made use of the phenomenon of reversiblehzemolysis.When red cells are lysed, the membranes become permeable tohzemoglobin and other solutes within the cell, and yet the subsequentaddition of 3~-sodium chloride to restore isotonicity causes the membranesto become again impermeable to h a e m o g l ~ b i n . ~ ~ ~ ~ ~ The reconstituted cells,or ghosts, behave as osmometers in solutions of various non-penetratingsolutes. Ghosts with a low permeability towards sodium and potassiumare best prepared by incubating the hzemolysate, after the addition of saltto restore isotonicity, for about 30 min.at 37°.91 The ghosts may then besuspended in a physiological saline medium and their membrane propertiesstudied in the absence of the complications that arise from the presence ofendogenous metabolites, which are removed during lysis. Reconstitutedcells prepared in this way have been shown to accumulate potassium when asubstrate for glycolysis is provided.92 Ghosts have also been prepared fromcells that had been lysed in a dilute solution of ATP, and an active accumul-ation of potassium, insensitive to arsenate, was found in the absence oflactic acid prod~ction.~~ Hoffman 94 reports that ATP supports an activeefflux of sodium which does not occur with inosine triphosphate or ADP;this work has not been described in full, but it appears from the abstracts85 R.Whittam, J . Plzysiol., 1958, 140, 479.86 E. T. Dunham, Fed. PYOG., 1957, 16, 33.87 E. Gerlach, A. Fleckenstein, and E. Gross, Pjlug. Arch. ges. Physiol., 1958, 266,628; E. Gerlach, A. Fleckenstein, and K. J. Freundt, ibid., 1957, 263, 682; T. A. J.Prankerd and K. I. Altman, Biochern. J., 1954, 58, 622.88 L. E. Bayliss, J . Physiol., 1924, 59, 48.89 J. F. Hoffman, J . Gen. Physiol., 1959, 42, 9.90 T. Teorell, J . Gen. PhysioZ., 1952, 35, 669.91 J. F. Hoffman, D. C. Tosteson, and R. Whittam, Nature, 1960, 185, 186.S2 J. F. Hoffman and D. C. Tosteson, Proc. 20th Internat. Physiol. Congr., 1956,93 G. Gardos, Acta Physiol. Acad. Sci. Hung., 1954, 6, 191; F. B. Straub, ibid.,94 J. F. Hoffman, Fed. Proc., 1960, 127.p.429.1954, 4, 235390 BIOLOGICAL CHEMISTRY.that human red-cell membranes are able selectively to transport sodiumand potassium ions against concentration gradients provided ATP is presentand in the absence of lactic acid production.Nerve. Three papers have appeared giving results on the effects of theinjection of ATP and other phosphate esters on the efflux of sodium fromsquid giant nerve axons. It had been shown previously that the sodiumefflux and potassium influx in giant axons of cephalopods are reduced bymetabolic inhibitors17 and by anoxia,65 and this work raised the questionwhether their effects might be due to interference with reactions involvingATP. Caldwell 95 showed that cyanide and 2,4-dinitrophenol, at suitablepH,96 caused falls in the concentrations of ATP and arginine phosphate thatran parallel with the reductions that these inhibitors caused in the sodiumefflux.A technique had been developed for the injection of material intogiant axons by means of a fine pipette attached to a syringe inserted longi-t ~ d i n a l l y , ~ ~ and this method was used for the injection of phosphate estersinto poisoned axons, in which the normal active transport of sodium wasblocked. The injection of arginine phosphate or phosphoenolpyruvaterestored the normal efflux of sodium that is coupled to the entry of potassium,and the injection of ATP increased only the sodium efflux that is indepen-dent of potassium infl~x.~8 Thus, the effects of arginine phosphate and ofphosphoenolpyruvate on the sodium efflux were abolished by the removal ofpotassium from the outside saline medium, although the effect of ATP wasunaltered. It is suggested that the greater effects of arginine phosphate andof phosphoenolpyruvate might arise from the regeneration of ATP as soonas it is hydrolysed by reactions similar to those catalysed by creatine phospho-kinase, viz.:Creatine phosphate + ADP = Creatine + ATPArginine phosphate + ADP = Arginine + ATPand by pyruvate kinase, viz. :Phosphoenolpyruvate + ADP = Pyruvic acid + ATPA higher ratio ATP : ADP might therefore be maintained near the mem-brane after injection of either arginine phosphate or phosphoenolpyruvatethan after injection of ATP. The experiments support the view thatmetabolism drives the cation-transport system by formation of compoundssuch as arginine phosphate and ATP.Support for the view that argininephosphate is important was found by studying in detail the effects of poison-ing with cyanide and 2,4-dinitrophenol on sodium efflux. In conditionssuch that the concentrations of both arginine phosphate and ATP werereduced, the sodium efflux coupled to potassium influx was also reduced,and, when the concentration of ATP was maintained but that of argininephosphate was reduced, the coupled sodium-potassium transport wasabolished.99 Very little is known about the intermediary metabolism of95 P. C . Caldwell, J . Physiol., 1960, 152, 545.96 P. C. Caldwell, Biochem. J., 1957, 67, 1 ~ .97 A. L. Hodgkin and R. D. Keynes, J.Physiol., 1956, 131, 592.98 P. C . Caldwell, A. L. Hodgkin, R. D. Iceynes, and T. I. Shaw, J . Physiol., 1960,99 P. C. Caldwell, A, L. Hodgkin, R. D. Keynes, and T. I. Shaw, J . PhysioE., 1960,152, 561.162, 591WHITTAM CHEMICAL ASPECTS OF ACTIVE TRANSPORT. 391giant nerve axons, and the effects of the metabolic inhibitors and of theinjection of phosphate esters on the rates of respiration and of lactic acidproduction, which have not yet been measured, appear to be relevant to theinterpretation of the studies on sodium efflux.Adenosine Triphosphatase.-The evidence for the participation of enzyme-like protein in the transport of certain organic compounds such as sugarsand carboxylic acids is strong,lW but only recently have enzymes beenimplicated in the active transport of cations.Discussion of possible systemsfor cation transport originates from Osterhout’s work with marine algze,lolbut nothing definite has been known about their chemical nature. Theinvolvement of enzymes in a transport process need not present moredifficulties than the migration of any other carrier molecule between thetwo surfaces of a membrane. The evidence already discussed indicatesthat ATP is probably somehow involved in active transport in human redcells and giant axons of crustacean nerves, and various studies of the adeno-sine triphosphatase (ATPase) in these cells have been undertaken to see ifthis enzyme might be connected intimately with the transport process.ATPase activity in the sheath of giant nerve axons 1029103 and in peripheralnerves from the rat lo3 has been described. Nerves from the shore crab(Carcinzts maenas) appear to contain two kinds of ATPase, the activity ofwhich may be increased by the addition of calcium or magnesium, sever-ally.104 The enzyme in crab nerve activated by magnesium is localisedin submicroscopic particles, as is also the enzyme from the sheath of giantaxons.An ATPase isolated from muscle was also activated by magnesiumand strongly inhibited by calcium.lo5 The important recent discovery isthat the ATPase from crab nerve that is activated by magnesium is furtheractivated when sodium is present as well as magnesium, and still furtheractivated on the concomitant addition of potassium in small concen-trations.lM A similar observation has been made with a brain prepar-ation.lo6 The presence of magnesium is obligatory for any activity of theenzyme and hence for the further activation by sodium and potassium.The effect of potassium depended on its concentration, because high concen-trations inhibited the activity due to sodium, although the activity due tomagnesium was unaffected.The effect of calcium was entirely inhibitoryunder all conditions. When the enzyme preparation contained sodium,potassium, and magnesium in concentrations equal to those in the nerveaxoplasm, decrease in the potassium concentration, as well as increase inthe sodium concentration, increased the enzyme activity. These are thepassive changes in the intracellular sodium and potassium concentrationsthat occur on stimulation of nerves l9 which are later reversed more slowlyby active transport.It was therefore suggested that ATPase may be in-volved in the active movements during the recovery of the concentration100 G. N. Cohen and J. Monod, Bact. Rev., 1967, 21, 169.101 W. J. V. Osterhout, Ergebn. Physiol., 1933, 35, 967.102 B. Libet, Fed. Proc., 1948, 7, 72.103 L. G. Abood and R. W. Gerard, J . Cell. Comp. Physiol., 1954, 43, 379.104 J. C. Shou, Biochim. Biophys. Acta, 1957, 23, 394.105 W. W. Kielly and 0. Meyerhof, J . Biol. Chem., 1948, 178, 691.106 H. Hess and A. Pope, Fed. Proc., 1957, 16, 196392 BIOLOGICAL CHEMISTRY.gradients after stimulation. The different activating effects of sodium andpotassium suggest that they may differ in their site of activation of theenzyme and that the inhibitory effect of potassium at high concentrationsmay be due to an interference with sodium activation.If the substrate ofthe enzyme is Na-Mg-ATP, the various effects could be explained. It wasnot suggested that covalent bond between sodium and ATP is formed, andthe details of the reaction have not been completely elucidated.A later study lo7 of the enzyme showed that an inhibitor of active trans-port, namely, strophanthin, inhibited the activating effect of sodium, andof sodium and potassium added together. It is now further suggested thatthe enzyme is phosphorylated and that the phosphorylation occurs onlywith magnesium. The liberation of orthophosphate from the enzyme-substrate complex appears to be the step that is activated, either by sodiumalone or by sodium and potassium together.[Cardiac glycosides, e.g.,digoxin and strophanthin (or ouabain) have a powerful inhibitory effect onactive transport on such diverse tissues and cells as human red ~ells,~O~JO~J10frog skin,lll giant nerve axons,l12 gastric m u c o s i ~ , ~ ~ ~ frog sartorius muscle,ll4ascites tumour and the thyroid gland; Il6 they have been assumedto act directly on a membrane carrier involved in the active transport or toact as carrier molecules,117 and not to inhibit the rates of aerobic or anaerobicmetabolism; the evidence for the latter belief is, however, scanty, and islargely the fact that glycolysis is not inhibited in red ce1ls,1o9 even thoughthis lack of effect probably does not apply to other, more complex cells.]Recent work with fragmented membranes, obtained by the lysis ofhuman red cells, has shown that they also liberate orthophosphate from ATPby a catalyst that is activated by sodium and potassium ions in the presenceof magnesium.l18 Nine characteristics of the mechanism of hydrolysis ofATP were similar to those of the active transport process.Thus, forexample, both the enzyme and the transport system are located in the mem-brane, the activation due to potassium was also obtained with ammoniumions, and the concentrations at which potassium and ammonium ionsshow half their maximal effects are the same in the two processes. A furthersimilarity 119 is that the inhibition by a cardiac glycoside (scillaren) can beovercome by raising the potassium concentration, as can its inhibition ofpotassium influx into intact cells.l1° There are considerable differences inthe potassium concentration in red cells of different mammalian species and,107 J.C. Skou, Biochim. Biophys. Acta, 1960, 42, 6.108 C. R. B. Joyce and M. Weatherall, J . Physiol., 1955, 127, 3 3 ~ ; J. B. Kahn100 H. J. Schatzmann, Helv. Physiol. Pharmacol. Acta, 1953, 11, 346.110 I. M. Glynn, J . Physiol., 1957, 136, 148.111 V. Koefoed-Johnsen. Acta Physid. Scand., 1957, 42, Suppl. 145, p. 87.112 P. C. Caldwell and R. D. Keynes, J . Physiol., 1959, 148, 8 ~ .113 I. L. Cooperstein, J . Gen. Physiol., 1959, 42, 1233.114 J. A. Johnson, Amer.J . Physiol., 1956, 187, 328; C. Edwards and E. J. Harris,115 M. Maizels, M. Remington, and R. Truscoe, J . Physiol., 1958, 140, 61.116 J. Wolff and J. R. Maurey, Nature, 1958, 182, 957.117 W. Wilbrandt, Schweiz. med. Woch., 1959. 14, 363.118 R. L. Post, C. R. Merritt, C. R. Kinsolving, and C. D. Albright, J . Biol. Chem.,119 E. T. Durham and I. M. Glynn, J. Physiol., 1960, 152, 6 1 ~ .and G. H. Acheson, J . Pharmacol. Ex+. Therap., 1955, 115, 305.J . Physiol., 1957, 135, 567.1960, 235, 1796WHITTAM : CHEMICAL ASPECTS OF ACTIVE TRANSPORT. 383in the case of sheep, even within the same species. It is, therefore, significantthat sheep red cells with a low potassium concentration are reported topossess lower ATPase activity sensitive to sodium and potassium ions thanred cells of the same species that contain a high potassium concentration.lmThis recent work suggests that a system for hydrolysing ATP may be partof the mechanism responsible for active movements of sodium and potassiumions in crab nerve and in human and sheep red cells.Phosphatidic Acid.-The occurrence of phosphoglycerides in brain andnervous tissue, and in cell membranes, is well-known but their function isnot yet understood.121 An important member of this class of compound isphosphatidic acid (diacylglycerophosphoric acid), which is involved in thesynthesis of phospholipids and triglycerides.When secretion is stimulatedfrom slices of the pancreas in v i t ~ o , ~ ~ ~ and also after the addition of acetyl-choline to brain-cortex slices,123 there is a marked increased in the turn-overof the phosphate of phosphoinositide and phosphatidic acid.The suggestion 124 that phosphatidic acid may be the carrier for thetransport of cations across cell membranes merits careful consideration, as itleads to critical experimental tests and also accounts for some of the knownfacts about the transport process.Thus, phosphatides form lipoid-solublecomplexes with cations and solubilise sodium or potassium chloride in asolution of light petr01eum.l~~ A preference for potassium over sodium of10 : 1 has been noted with pure phosphatides.126 Other evidence in favourof the suggestion is that the stimulation with acetylcholine of slices of thesalt gland of the albatross causes an increased turn-over of phosphatidicacid.127 Acetylcholine causes a secretion of sodium chloride in vivo 128and, although the secretion could not be measured from slices of the glandin vitro, an increase in oxygen consumption, which also accompanies secretionin other tissues, was observed on the addition of acetylch01ine.l~' Theincreased turnover of phosphatidic acid was, therefore, thought to beassociated with the secretory activity both in slices of pancreas and in thesalt gland of the albatross.The enzymes necessary for the turn-over arepresent in the gland, viz. , diglyceride kinase, to form phosphatidic acid fromdiphosphoglycerate and ATP, and phosphatidic acid phosphatase, to causehydrolysis :ATP + Diglyceride = ADP + Phosphatidic acidPhosphatidic acid = Diglyceride + OrthophosphateAs phosphatidic acid is dibasic, a maximum of two sodium ions could besecreted for the turn-over of one molecule of phosphatidic acid and, with a120 D.C . Tosteson, R. H. Moulton, and M. Blaustein, Fed. Proc., 1960, 19, 128.le1 R. M. C. Dawson, Ann. Reports, 1958, 55, 365; Biol. Rev. Camb. Phil. SOC.,lZ2 L. E. Hokin and M. R. Hokin, J . B i d Chem., 1958, 233, 800, 805; Biochim.123 L. E . Hokin and M. R. Hokin, J . Biol. Chem., 1958, 2W, 818.I24 L. E. Hokin and M. R. Hokin, Internat. Rev. Neurobiol., 1960, 2, 99.126 A. K. Solomon, F. Lionetti, and P. Curran, Nature, 1956, 178, 582.127 L. E. Hokin and M. R. Hokin, J . Gen. Physiol., 1960, 44, 61.128 R. Fange, K. Schmidt-Nielsen, and M. Robinson, Amer. J .PhysioE., 1958,1957, 32, 188.Biophys. Acta, 1955, 18, 102.H. N. Christensen and A. B. Hastings, J. BioZ. Chem., 1940, 136, 387.195, 321394 BIOLOGICAL CHEMISTRY.phosphorylation quotient assumed to be 3, a maximum of twelve sodiumions could be secreted per molecule of oxygen used in respiration. Furtherwork is in progress in several laboratories to test whether the turn-over ofphosphatidic acid accompanies active transport in non-secreting cells , suchas red blood cells and muscle and nerve fibres, and also whether the rate ofturn-over of phosphatidic acid is compatible with the observed rates ofcation transfer.Microbial Permeases.-Important discoveries about the penetration oforganic compounds into micro-organisms have originated from the study ofthe " adaptive " formation of enzymes in bacteria.An example is providedby the bacterium, E. coli, which is normally unable to utilise lactose as asource of energy because it lacks the enzyme, p-galactosidase. (This enzymecatalyses the hydrolysis of lactose to galactose and glucose.) When grownin the presence of lactose, however, the synthesis of this enzyme is inducedand the organism therefore becomes adapted to the use of lactose. Com-pounds similar to lactose, such as methyl and butyl p-D-galactoside, arehydrolysed by the enzyme and also induce its formation provided they arepresent during the growth of the cells.129 Monod made the importantobservation that although the sulphur analogues of these compounds(methyl and butyl P-thiogalactoside) are not hydrolysed by p-galactosidase,they nonetheless induce its synthesis.loO Whilst studying the process ofenzyme formation induced by methyl p-thiogalactoside, it was found thatthis compound is accumulated within the cells in a concentration about fiftytimes higher than that in the external medium.100 The uptake was com-petitively inhibited by a similar compound, phenyl P-thiogalactoside, it hada high temperature-coefficient between 0" and 37O, and it was prevented byinhibitors of metabolism such as azide and 2,4-dinitrophenol.The high concentration of methyl p-thiogalactoside in the cells was notdue to chemical binding to the enzyme because the compound was osmotic-ally active.130 Methyl p-thiogalactoside can, therefore, be actively trans-ported into the cells, and lactose, o-nitrophenyl p-galactoside and p-thio-digalactoside also appear to be transported by the same mechanism.Thefact that the uptake occurs when synthesis of protein has been permittedleads to the suggestionloo that, besides the synthesis of p-galactosidase, afurther specific protein, termed galactoside permease, is formed which isresponsible for the active uptake. It is necessary to assume that an inter-mediate complex is formed between the substance accumulated and thepermease, similar to the complex formed between an enzyme and its sub-strate. Although the permease shows some of the properties of an enzyme(specificity and competitive inhibition) it differs from an enzyme in changingthe location instead of the chemical nature of the substrate.The permeationmechanism is distinct from the metabolic enzymes involved in the degrad-ation of metab01ites.l~~Further instances have been reported of specific transport mechanismsinvolving a protein, the formation of which is induced by exposure of the129 M. Cohn, Bact. Rev., 1957, 21, 140.130 W. R. Sisfxom, Biochim. Biophys. Acta, 1958, 29, 679.131 B. L. Horecker, J. Thomas, and J. Monod, J . Bid. Chem., 1960, 235, 1580REDFEARN : ELECTRON TRANSPORT AND OXIDATIVE PHOSPHORYLATION. 396organism to the compound that is later accumulated. Thus, Davis demon-strated a mechanism for the uptake of citrate by Aerobacter aerogenes whichhad been grown in the presence of ~itrate.1~2 This adaptation to citraterequired the formation of the transport mechanism only, because theenzymes which degrade citrate were already present in the unadapted cells.During the lag period that occurs before several other intermediates of thetricarboxylic acid cycle are oxidised by micro-organisms, a transport mechan-ism is induced that allows access of the substrates to the enzymes alreadypresent.There is evidence that separate permeases exist in some Pseado-monads for the transport of citrate, acetate, fumarate, succinate, a-oxo-glutarate, malate , and pyruvate.l= In another micro-organism, Coryne-bacterium erythrogenes, a common inducible permease transports bothsuccinate and malate.la Permeases in other micro-organisms may alsocause the accumulation of amino-acids, tartaric acid, and phenyl P-thio-glucuronide (see ref.100). The above studies have, therefore, clearlyestablished that specific proteins with properties similar to enzymes controlthe entry of some organic substances into micro-organisms.R. W.5. ELECTRON TRANSPORT AND OXIDATIVE PHOSPHORYLATIONELECTRON TRANSPORT and the associated process of oxidative phosphoryl-ation are among the most active fields of biochemical research at the presenttime and considerable progress has been made since the subject was lastreviewed in these Reports ten years ago. In the present review an attemptwill be made to present a broad picture of recent progress and current views.The electron-transport system or the respiratory chain is the systemwhereby the metabolites derived from carbohydrates, proteins, and fats areoxidised and the energy released is conserved and stored as adenosine tri-phosphate (ATP).The overall process may be represented by equation (1).2AH, + 0, --+ 2A f 2H,O + Energy (I)The hydrogen atoms do not react with oxygen in a single step; thiswould be a wasteful process. Instead they are transferred through asequence of hydrogen- and electron-carriers and at various stages the energyreleased is conserved by the esterification of inorganic phosphate to affordATP. The principal components of the electron-transport system or respir-atory chain are the dehydrogenases, pyridine nucleotides , flavoproteins ,cytochromes, and probably quinones. Each oxidisable substrate has itsown specific dehydrogenase.These are protein enzymes which activatethe substrate and catalyse the transfer of the hydrogen atoms to the firstcarriers in the system , the di- and tri-phosphopyridine nucleotides (DPN orCo I, and TPN or Co 11). From the pyridine nucleotides the pairs ofhydrogen atoms are transferred to a flavoprotein and, from there, electronsare carried by the cytochromes to the enzyme, cytochrorne oxidase, which132 B. D. Davis in 0. H. Gaebler (editor), " Enzymes: Units of Biological Structureand Function," Academic Press, Inc., New York, 1956.133 P. H. Clarke and P. M. Meadow, J . Gen. Microbiol., 1959, 20, 144.134 R. G. Tucker, J. Gen. Microbiol., 1960, 23, 267396 BIOLOGICAL CHEMISTRY.catalyses the reduction of oxygen to water.In the case of succinic acid,the dehydrogenase is a flavoprotein which itself carries the hydrogen atomsand transfers electrons to the cytochromes. This is because the oxidation-reduction potential of the succinate-fumarate system is more positive thanthose of the other dehydrogenase systems and does not permit reduction ofthe pyridine nucleotides. Thus hydrogen atoms can be fed into the respir-atory chain from two sources, the pyridine nucleotides and succinate.It is now well established that the electron-transport and oxidative-phosphorylation systems of animal and plant cells are localised in the solidphase (membranes and cristae) of the mitochondria.l These are smallintracellular structures, usually rod-shaped, about 3-5 in length and0-2-0+5 p in diameter.Electron microscopy has shown that they consistof an outer double membrane, which is probably lipoprotein, with deepunfoldings of the membrane (cristae) into the interior of the mitochondrion.The inner fluid matrix appears to contain soluble enzymes of the tricarboxylicacid cycle. The concept of the respiratory chain as an organised structuralsystem rather than a simple mixture of the various components was stressedmany years ago by D. E. Green. Recently, Green has even gone so far asadvancing the idea that the mitochondrion can be visualised ‘‘ as a giantmacromolecule or supramolecule which is no different except in respect tosize from macromolecules such as proteins.” While some may disagreewith such a rigorous concept there is fairly general agreement that therespiratory-chain carriers are embedded in the lipoprotein framework of themitochondria in a particular spatial arrangement which allows a rapid flowof electrons from the substrate to oxygen via the appropriate carriers withthe concomitant formation of ATP from ADP and inorganic phosphate.The mitochondrion is the principal site of energy conservation in the celland can be thought of as a biochemical machine which oxidises intermediatesof the citric acid cycle and conserves the energy released as ATP, the prin-cipal energy currency of living organisms.In the intact organism the efficiency of the coupling of phosphorylationto electron transport is probably regulated by metabolic and hormonalcontrol mechanisms according to energy requirements.In isolated mito-chondria oxidative phosphorylation is exceedingly labile and can readily beuncoupled from electron transport. For example, when mitochondria are“aged” simply by incubating them at 37” or are subjected to variouschemical or mechanical treatments, phosphorylation is abolished butelectron transport may not be affected. Uncoupling in these cases hasprobably been induced by disruption of the mitochondrial structure andthe loss of certain essential factors. However, certain potent uncouplingagents, such as 2,4-dinitrophenol, do not affect the structure but probablyact on specific enzyme systems concerned in oxidative phosphorylation.Most of the pioneering work on the structure and function of the respir-atory chain has been done on mitochondrid preparations which have lost1 G.E. Palade, in ‘ I Enzymes: Units of Biological Structure and Function ’ I (ed.0. H. Gaebler):,Academic Press, New York, 1956; P. Siekevitz, in Ciba FoundationSymposium ona D. E. Green, Adv. Enzymol., 1959, 21, 73.The Regulation of Cell Metabolism,” Churchill, London, 1969mDFEARN ELECTRON TRANSPORT AND OXIDATIVE PHOSPHORYLATION. 397the capacity for oxidative phosphorylation during the course of isolation.Thus the preparations used by Keilin and Hartree are now recognised asnon-phosphorylating fragments of heart-muscle mitochondria (sarcosomes) .3These particles are probably also identical with the electron-transportparticles (ETP) described by Green and his associates.2 These non-phos-phorylating preparations do not contain the complete sequence of com-ponents ; they have lost all the DPN-specific dehydrogenases and boundDPN, but they still oxidise DPNH, and succinate.It is interesting that theintact mitochondrion will not oxidise external DPNH,.Recently various authors have described techniques for obtaining sub-mitochondrial particles which still possess the ability of oxidative phos-phorylation. These have proved very useful in studies on the mechanism ofphosphorylation (see below).Nature and Sequence of Components of the Electron-transport System.-The pioneering work of Keilin’s school on the spectroscopic identificationand the structure of the respiratory chain formed the basis of the presentconcepts. This early work has been developed and extended by Slater,Chance, Green, and other workers largely through the application of newand powerful techniques. Green and his group, have been particularlysuccessful in the development of procedures for the fractionation of mito-chondria.Using organic solvents and surface-active agents coupled withhigh-speed centrifugation they have been able to obtain a number of mito-chondrial fragments containing one or more components of the respiratorychain. These have yielded valuable information on the structure of theelectron-transport system and the properties of the individual components.It is hoped that these studies will eventually lead to the reconstitution of theelectron-transport system from its component parts.The components of the respiratory chain have characteristic absorptionspectra in the oxidised and the reduced forms.This fact is made use of byChance and his colleagues who have studied the reactions of the componentsof the respiratory chain in sitw, using sensitive spectrophotometers.Chance’s double-beam spectrophotometer consists of two monochromators,one of which is set on the absorption peak of the carrier being studied whilethe other is set at a reference wavelength where the absorption differencebetween the oxidised and the reduced state is negligible. The light fromeach monochromator is then switched alternately through the particlesuspension and the output from the “ end-on ’’ photomultiplier is amplifiedand fed to a suitable recorder. In this way the rate of change of absorbancydifferences at the two wavelengths can be measured.The main components of the electron-transport system are.the dehydro-genase enzymes specific for each substrate, the pyridine nucleotide co-C. Cooper and A. L. Lehninger, J . B i d . Chem., 1956,219, 489; W. W. Kielley andJ..R. Bronk, ibid., 1958, 230, 521; W. W. McMurray, G. F. Maley, and H. A. Lardy,zbzd., p. 219; D. M. Ziegler, R. L. Lester, and D. E. Green, Biochim. Biophys. A&,1956, 21, 80.B. Chance and G. R. Williams, Adv. Enzynzol., 1956, 17, 65; B. Chance, in Proc.Internat. Symposium on Enzyme Chemistry, Tokyo and Kyoto, 1967, Pergamon Press,London, 1958.8 E. C. Slater, Adv. EnzymoE., 1958, 20, 147.6 D.Keilin and E. C. Slater, Brit. Med. Bull., 1953, 9, 89398 BIOLOGICAL CHEMISTRY.enzymes, the flavoproteins, and the cytochromes. In addition, certain lipidcofactors (e.g., quinones) and metal ions may prove to be essential com-ponents. All these components appear to be embedded in the mitochondriato form an organised structural system. This has made the isolation ofmost of the individual carriers difficult. Exceptions are the water-solublecarriers, the pyridine nucleotides and cytochrome c, and the lipid-solublequinone, ubiquinone (coenzyme Q), which can be readily isolated andpurified.In the last few years, however, there has been considerable progress inthe development of techniques for the isolation of the other components.Succinic dehydrogenase has been isolated in a pure form and shown to be aflavoprotein.' It can be obtained in two forms; one isolated from freshpreparations of beef heat mitochondria always contained 4 atoms of ironper mole of flavin, while a less active enzyme with 2 atoms of iron per moleof flavin was obtained from mitochondrial acetone powders which had beenkept for several months.Attempts are now being made to isolate and purifythe flavoprotein specific for the dehydrogenation of DPNH,.8The cytochromes are haemoproteins which act as electron carriers byvirtue of the reversible oxidation-reduction of the iron atom; the reducedform (ferrocytochromes) exhibit sharp selective absorption bands in thevisible region. The three groups of cytochromes, a, b, and c, have differenthzem prosthetic group^.^ Cytochrome c, first isolated by Keilin many yearsago, has now been cry~tallised.~ Recently it has been claimed that thewater-soluble form is an isolation artifact and that the actual functionalform in the intact particle is a lipid-soluble cytochrome c.l0Wainio,ll Green,2 Okunuki,12 and Stotz l3 and their colleagues haveapplied fractionation techniques which have led to the isolation of highlypurified preparations of cytochromes b, cl, and a (or a + a3).Keilin 5 in his early work had shown that '' cytochrome a " actuallyconsisted of two spectroscopically distinguishable cytochromes, a and a3,and that the a3 component was a very autoxidisable member of the respir-atory chain. Thus, cytochrome a3 was identified with cytochrome oxidase.Subsequently it was shown that a and a3 always occur together in constantproportions and that they could not be physically separated.It has beensuggested therefore, that a + a3 is a single entity consisting of two differentprosthetic groups attached to the same protein; this complex is oftenreferred to as cytochrome oxidase. Others workers 2*12 are doubtful aboutthe existence of two different prosthetic groups and designate cytochromeoxidases simply as cytochrome a.7 T. P. Singer, E. B. Kearney, and V. Massey, Adv. EnzymoE., 1957, 18, 65.8 T. E. King and R. L. Howard, Biochim. Biophys. Acta, 1960, 37, 557; R. L.Ringler, S. Minakani, and T. P. Singer, Biochewz. Biophys. Res. Comm., 1960, 3, 417.9 G.Bodo, Nature, 1955, 176, 829; B. Hagihara, I. Morikawa, I. Sekuzu, T. Horio,and K. Okunuki, ibid., 1956, 178, 630.10 C. Widmer and F. L. Crane, Biochim. Biophys. Acta, 1958, 27, 203.11 D. Feldman and W. W. Wainio, Science, 1959, 130, 796.12 K. Okunuki, B. Hagihara, I. Sekuzu, and T. Horio, in Proc. Internat. Symp. on1s L. Smith and E. Stotz, J . Biol. Chem., 1954, 209, 819; C. Widmer, H. W. Clark,Enzyme Chemistry, Tokyo and Kyoto, 1957, Pergamon Press, London, 1958.H. A. Neufeld, and E. Stotz, ibid., 1954, 210, 861REDFEARN : ELECTRON TRANSPORT AND OXIDATIVE PHOSPHORYLATION. 399The presence of copper in purified cytochrome oxidase is interesting andits role is now being investigated.14 The mechanism of action of cyto-chrome oxidase has been the subject of a number of recent papers.15Studies on the stoicheiometric relations of the components of the respir-atory chain in various mitochondrial preparations have indicated that thevarious cytochromes are present in approximately equimolecular concen-trations6 In ETP the flavin concentration appears to be roughly stoicheio-metrically equivalent to the cytochromes,2 but in rat liver mitochondria theratio of flavin to cytochrome a is 3.6 : 1, while the corresponding ratio forpyridine nucleotide is 19 : 1.A number of authors have put forward schemes showing the pathwaysof hydrogen and electron carriers in the respiratory chain.These differ ona number of points but the main controversy centres on the position ofcytochrome b.Probably the simplest scheme is that favoured by Chancefor the phosphorylating system (Fig. 1). This forms a useful basis for thediscussion of the other schemes.Amytal Antirnycin ABALI v vDPNH, ~ P D\cyt.b + cyts,Succinate fps IAioxaloacetaternalonate* cyt.cicyt.a __t cyt.a, __t 0,Cyanide,aideFIG. 1. The Phosphorylating electron transport system and sites of action of inhibitors.( f p , = DPNH, dehydrogenase $avoprotein, f p s = succinic dehydrogenase $avo-$rote in .)This scheme is consistent with the standard oxidation-reduction poten-tials of the carriers, with the action of inhibitors, and with Chance’s kineticstudies of intact phosphorylating mitochondria. In non-phosphorylatingheart-muscle preparations of the Keilin-Hartree type, the kinetics of theoxidation-reduction of cytochrome b are not consistent with its position onthe main respiratory pathway.Chance has therefore proposed that cyto-chrome b is by-passed in the non-phosphorylating system. This view hasbeen criticised by Slater,3 who finds it difficult to accept a fundamentalchange in the pathway without loss of efficiency when phosphorylation isuncoupled. Slater’s view is that cytochrome b is part of the succinic oxidasel4 S. Takemori, I. Sekuzu, and K. Okunuki, Biochim. Biophys. Acta, 1960, 38,158; R. H. Sands and H. Beinert, Biochern. Biophys. Res. Comm., 1960, 1, 175; C. V.Wende and W. W. Wainio, J . Biol. Chem., 1960, 235, PC 11.l5 T. Yonetani, J . Biol. Chem., 1960, 235, 845; J. H. Wang and W.S. Brinigar,Proc. Nat. Acad. Sci. U.S.A., 1960, 48, 958; I. Sekuzu, S. Takemori, Y . Orii, and K.Okunuki, Biochim. Biophys. Acta, 1960, 37, 64; T. E. King and C. P. Lee, ibid., p. 342400 BIOLOGICAL CHEMISTRY.system, but not of the DPNH, oxidase system, in both phosphorylating andnon-phosphorylating particles. A third and different view is taken byGreen and his school 2y16 who suggest that cytochrome b lies off the succinate-and DPNH,-oxidising chains under all conditions. This raises the questionof the precise function of cytochrome b in the electron-transport system. Isit concerned in some ancillary function such as a biosynthetic process, or isit essential for electron transport and oxidative phosphorylation in a morecomplex arrangement of carriers than has been considered hitherto? Thereis obviously a need for further investigation of this problem.There are four principal sites of action of inhibitors in the electron-transport system (see Fig.1). These are (i) cytochrome a3 (cytochromeoxidase), inhibited by cyanide, azide, and carbon monoxide, (ii) a site be-tween cytochromes b and cl, inhibited by antimycin A, British Anti-Lewisite(BAL) (2,3-dimercaptopropanol), the naphthaquinone antimalarials, and2-alkyl-4-hydroxyquinoline oxides, (iii) a site between DPNH, and flavo-protein in phosphorylating preparations, inhibited by sodium amytal,though in non-phosphorylating preparations the inhibitory site moves to apoint between the flavoprotein and cytochrome b, and (iv) succinic dehydro-genase inhibited by oxaloacetate and malonate which, unlike the others, isa competitive inhibition.Studies with BAL led Slater to postulate the presence of an additionalfactor between cytochromes b and cl.There appears to be some evidencethat this factor is different from the antimycin A-sensitive region but thisis not completely convincing. Recent work l7 has implied that at least thenaphthaquinone inhibitors probably act by virtue of a non-specific physicaleffect. This would favour the view that the inhibitory site is a structuralfactor, perhaps of a lipid nature. A similar explanation may also apply toamytal-sensitive region, but the apparent movement of the site in the non-phosphorylating system is difficult to explain. Is this another manifestationof fundamental changes in the structure and sequence of carriers whenoxidative phosphorylation is uncoupled? It is interesting that the DPNH,-oxidising system is much more sensitive than the succinic oxidase systemto the action of surface-active agents and organic solvents; this points,perhaps, to the presence of a lipid-containing structural factor in the DPNH,system.The question whether separate and independently active respiratorychains serve the individual dehydrogenases, or all the dehydrogenases arelinked to a common electron-transport system, has been discussed recentlyby Kimura and Singer.ls These authors concluded from a study of thecholine and succinate oxidase systems of rat-liver mitochondria that thepathway of carriers from cytochrome c1 to a3 was common to both systems.This supported earlier work19 which indicated that the DPNH, and thesuccinate oxidase system of Keilin-Hartree preparations had a commonpoint of fusion.An alternative view that separate chains exist for the16 D. E. Green and R. L. Lester, Fed. Pvoc., 1959, 18, 987.17 D. Hendlin and T. M. Cook, Biochem. Biophys. Res. Cornm., 1960, 2, 71.18 T. Kimura and T. P. Singer, Nature, 1959, 184, 791.19 C. Y. Wu and C. L. Tsou, Sci. Sinica, 1956, 4, 137REDFEARN : ELECTRON TRANSPORT AND OXIDATIVE PHOSPHORYLATION. 401oxidation of succinate and DPNH, has been advanced by Green., TheETP has been likened to a sandwich made up of the two chains. It isclaimed that the sandwich can be separated to give a preparation with onlyDPNH,-oxidising activity; however, the corresponding succinic oxidaseparticle has not yet been isolated. A more likely explanation of theseresults is that the isolation procedure results in selective destruction of oneof the oxidising activities.20It is convenient at this point to explain the terminology used to describethe various enzyme systems of the respiratory chain.The activities of thevarious enzyme systems which make up the respiratory chain are deter-mined by adding the appropriate substrate and then measuring the reductionof a natural or artificial hydrogen- or electron-acceptor which reacts withthe chain at a particular point. Thus succinic and DPNH, oxidase activitiesare a measure of the rate of oxidation of the substrate by the completesystem with molecular oxygen as the terminal acceptor.In measuring theactivity of cytochrome c reductase, cytochrome c is added to the prepar-ation and its rate of reduction measured spectrophotometrically afteraddition of the substrate; in this case cytochrome oxidase must be in-hibited with cyanide; it should be noted, however, that added cytochrome cis not as catalytically active as the bound material and that activities deter-mined by this method are, in terms of electron transfer, usually much lessthan those of the substrate oxidase. The activity of succinic dehydrogenaseis measured by the rate of reduction of phenazine methosulphate, an artificialdye which reacts with the Aavoprotein ; the activity of cytochrome oxidaseis measured by the rate of oxygen uptake in the presence of its substrate,reduced cytochrome c.The Role of Lipids in the Respiratory Chain.-It has been known for anumber of years that mitochondria contains relatively high concentrationsof lipid substances and that the phospholipids, which make up the majorpart, were probably important structural factors in the respiratory chain.,lThis idea was strengthened when electron microscopy revealed that themembranes and cristae are made up of what appear to be layers of phospho-lipid molecules sandwiched between layers of protein molecules.1 Thus theelectron-transport system is localised in a structure in which lipids play apredominant role.In the last few years there has been an intensification ofinterest in the role of lipid substances as structural and functional factors inelectron transport.Lipid analyses of rat-liver mitochondria, ETP, and Keilin-Hartree pre-parations have given values of, respectively, 23y0,22 34y0,22 and 38% ona dry-weight basis.In each case the predominant lipid was phospholipid,with smaller amounts of cholesterol and neutral lipids.An interesting approach to the problem of lipid function in electrontransport was that used by Nason and his colleague^.^^ In this, the prepax-ation (skeletal- or heart-muscle particles) was shaken with an organic solvent20 M. Klingenberg and T. Biicher, Ann. Rev. Biochem., 1960, 29, 669.2 1 E. G. Ball and 0. Cooper, J . Biol. Chem., 1949, 180, 113.22 M.J. Spiro and J. M. McKibbin, J . Biol. Chem., 1956, 219, 643.23 A. Nason and I. R. Lehman, Science, 1955, 122, 19; J . Biol. Chem., 1956, 222,511402 BIOLOGICAL CHEMISTRY.such as iso-octane, the layers were separated by a short spin in the centrifuge,and enzyme activities, such as the succinic- and DPNH2-cytochrome creductase, were determined. It was found that the solvent-treatmentusually resulted in a marked inactivation of these systems but that theycould be restored to their original levels by adding (+)-x-tocopherol as asuspension in bovine serum albumin. A hypothesis implicating tocopherolas an essential factor in electron transport was presented, even though thesame group of workers and others= found that other lipid substances,unrelated to tocopherol, would also reactivate the systems.It soon becameevident that the specificity of reactivation by tocopherol was doubtful and,as originally suggested by Deul et u Z . , ~ ~ it was shown first by Redfearn andPumphrey 26 and then by others 27 that the marked inactivation of enzymesystems after a short treatment with an organic solvent was due primarilyto the retention of small amounts of the solvent which acted as an inhibitor,rather than to the removal of lipid. The mechanism of reactivation bytocopherol and many other substances appeared to be removal or dispersalof the traces of inhibiting solvent. A further blow to the claim that toco-pherol was an essential component of the chain came when it was foundthat the relatively high concentration of tocopherol previously reported inmitochondrial preparations was in error because of the presence of anothersubstance with similar spectral and chemical properties.= Nevertheless,mitochondria do appear to contain a small amount of tocopherol and whileit is probably not functioning as an electron carrier it may serve in a pro-tective capacity by virtue of its antioxidant property.29Ubiquinone (Coenzyme Q).-The history of the discovery of the ubi-quinones, or coenzymes Q, by groups in Liverpool and Madison has beenadequately reviewed recently.30They are compounds which can be represented by the general formula (I),where m indicates the number of isoprenoid residues in the side-chain and( 1 )may be 6-10 in the naturally occurring quinones.They can be designatedas ubiquinone (50), (45), etc., or as CoQ,,,, etc., depending on the nomen-clature adopted. All the ubiquinones have the same absorption spectrawith a principal maximum (in ethanol) at 275 mp, an inflexion at 320 mp,24 K. 0. Donaldson, A. Nason, and R. H. Garret, J . Biol. Chem., 1958, 233, 572;F . Weber, U. Gloor, and 0. Wiss, Helv. Chim. Acta, 1958, 41, 1038, 1046.26 D. Deul, E. C. Slater, and L. Veldstra, Biochim. Biophys. Acta, 1958, 27, 133.26 E. R. Redfearn and A. M. Pumphrey, Biochim. Biophys. Acta, 1958, 30, 437;E. R. Redfearn, A. M. Pumphrey, and G. H. Fynn, ibid., 1960, 44, 404.27 C. J. Pollard and J. G. Bieri, Biochim. Biophys. Acta, 1958, 30, 658.28 J. Bouman, E. C. Slater, H. Rudney, and J.Links, Biochim. Biophys. Acta, 1958,29, 456.29 J. G. Bieri and A. A. Anderson, Arch. Biochem. Biophys., 1960, 90, 105.30 R. A. Morton, Nature, 1958, 182, 1764REDFEARN : ELECTRON TRANSPORT AND OXIDATIVE PHOSPHORYLATION. 403and a minor peak at 407 mp. On reduction to the quinol the maximumshifts to 290 mp with a fall in extinction; the 320 rnp inflexion and the 407 mppeak disappear. The distribution of the ubiquinones in various tissues hasbeen surveyed by a number of workers 31 and a summary is given in theannexed Table. It will be seen that the ubiquinones are widely distributedDistribdion of the ubiquinones.UQ(50); CoQ,, 49.9" 165 Human kidney, human liver, beef heart, pigkidney, cod heart, pike heart, rat liver, ratheart, Pseudomonas denitrifcans, Arum macu-latum spadixUQ(45); CoQ, 45-2 185 Rat liver, rat heart, housefly, bowfly larvae,walleyed pike, Rhodospirillum rubrum, Pseudo-monas pyocyanea, Torula utilisUQ(40); CoQ, 37 206 Escherichia coli, Proteus vulgaris, Azotobactervinelandii, Neisseria catarrhalis, Aerobacteraerogenes, Pasturella pseudotuberculosis, Ser-ratis marcescensUQ(35); CoQ, 30-5 221 Torula utilis, Chromatium sp.strain DUQ(30) ; CoQ, 19-20 260 Saccharomyces cerevisiae, Saccharomyces cava-* At 275 mp, in EtOH.Homologue M. p. El% 1Cm. * Distributionlieri, Saccharomyces fragilisin Nature. As a general rule there are relative large amounts in highlyaerobic tissues, but there are exceptions in the bacteria.In animal and higher plants the quinone is located principally in themitochondria.By using a method for determining the ubiquinone concen-tration in small amounts of mitochondrial preparations, it has been shownthat the concentration with respect to the individual cytochrome is veryhigh; e.g., in pig heart-muscle preparations the ratio of the molar concen-trations of ubiquinone to cytochrome c1 is 12 :Evidence that ubiquinone functions as an oxidation-reduction carrierin the respiratory chain is based on the facts that incubation of mitochondrialpreparations with intermediates of the tricarboxylic acid cycle underanaerobic conditions results in the reduction of the quinone, while onaeration the quinol is reoxidised,= and that the quinone specifically restoresenzymic activities in suitable extracted preparations.=The kinetics of the oxidation-reduction reactions of ubiquinone have beenstudied.35 It was shown that the rate of reduction of endogenous ubi-quinone by succinate or DPNH, or heart-muscle preparations was less thanthe rate of the overall electron-flux as measured by the substrate oxidaseactivities.Thus in a number of determinations, succinic-ubiquinonereductase rates were 13--52% of the succinic oxidase rates.31 R. L. Lester and F. L. Crane, J . Biol. Chem., 1959, 234, 2169; D. H. L. BishopK. P. Pandya, and H. K. King, unpublished work; J. F. Pennock, R. A. Morton, an;D. E. M. Lawson, Biochem. J., 1959, 73, 4 ~ ; €3. 0. Linn, A. C. Page, E. L. Wong, P. H.Gale, C . H. Shunk, and K. Folkers, J . Amer. Chem. Soc., 1959, 81 4007.32 A.M. Pumphrey and E. R. Redfearn, Biochim. J., 1960, 76, 61.33 F. L. Crane, Y . Hatefi, R. L. Lester, and C. Widmer, Biochirn. Biophys. Acts,1957, 25, 220; A. M. Pumphrey, E. R. Redfearn, and R. A. Morton, Chem. and Ind.,1958, 978.94 €2. L. Lester and S. Fleischer, Arch. Biochem. Biophys., 1959, 80, 470.35 E. R. Redfearn and A. M. Pumphrey, Biochem. J , , 1960, 76, 64404 BIOLOGICAL CHEMISTRY.The action of inhibitors on the oxidation-reduction reactions of ubi-quinone was also in~estigated.~~ Amytal inhibits the reduction of ubi-quinone with DPNH, as substrate, while malonate or oxaloacetate inhibitsthe reduction with succinate as substrate. Antimycin A has no effect onubiquinone reduction but it inhibits the oxidation of ubiquinol.Cyanidealso inhibits oxidation of ubiquinol. It appears that the site of action ofubiquinone is between the flavoproteins and the antimycin A-sensitiveregion.The mechanism of restoration of enzymic activities with ubiquinone andits derivatives in solvent-extracted preparations appears to be complex.Ambe and Crane 36 have carried out experiments with ETP and succinicdehydrogenase complex (SDC) which have been extracted with iso-octaneand acetone. SDC was prepared by treatment of ETP with deoxycholate.This preparation, previously referred to as the red fraction, contains a smallamount of cytochrome a, and when supplemented with cytochrome c itcatalysed the oxidation of succinate by oxygen. The main conclusions ofthis work were that SDC has three pathways involving cytochrome c (oroxygen) which respond to the addition of quinones.These are: (1) theantimycin-insensitive pathway to external cytochrome c induced by additionof menadione (2,3-methoxy-5-methylbenzoquinone) and short-chain ubi-quinone homologues; (2) the antimycin-sensitive pathway to external cyto-chrome c that can be induced only by homologues of ubiquinone [rangingfrom ubiquinone(50) to ubiquinone(lO)], but not by analogues of ubiquinonesuch as plastoquinone and the heptadecyl derivative; and (3) the antimycin-sensitive pathway to molecular oxygen which involves bound cytochrome cand can only operate in the presence of ubiquinone and its homologues,ubiquinone analogues (heptyl and heptadecyl), or plastoquinone. It wasfound also that a lipid component, NL 11, was essential for maximal restor-ation of succinic oxidase activity with ubiquinone homologues with morethan two isoprenoid units in the side chain.In contrast, ubiquinone(50)was maximally active without added NL I1 in the restoration of the activityof cytochrome c reductase of the same particle.Recently an enzyme system catalysing the reduction of ubiquinone bysuccinate has been isolated.37 It consists of a flavoprotein and cytochrome b,although it has been shown that the latter does not participate as an oxid-ation-reduction carrier in the reaction. Since pure succinic dehydrogenaseflavoprotein does not catalyse the reduction of ubiquinone by succinate, itis assumed that there is some other essential factor between the flavoproteinand the quinone in the active system.The precise position of ubiquinone as a hydrogen carrier in the respiratorychain has not yet been settled.Redfearn38 has discussed three possibleschemes on the basis of results obtained with non-phosphorylating prepar-ations (Fig. 2). In the first, ubiquinone is a member of the main respiratorychain acting between the flavoproteins and the antimycin A-sensitive factor.36 K. Ambe and F. L. Crane, Biochim. Biophys. Acta, 1960, 43, 30.37 D. M. Ziegler and K. A. Doeg, Biochem. Biophys. lies. Comm., 1960, 1, 344.38 E. R. Redfearn, in Ciba Foundation Symposium on ‘‘ Quinones in Electron Trans-port,” Churchill, London, 1961REDFEARN : ELECTRON TRANSPORT AND OXIDATIVE PHOSPHORYLATION.405The anomalous kinetics could then be explained by assuming that only aportion of the large excess of ubiquinone, with a fast rate of turn-over, wasactually required. This scheme is favoured by the Madison workers,presumably on the basis of extraction-reactivation experiments. In thesecond, the quinone is assumed to lie on a blind alley pathway reacting withthe flavoproteins only. In this scheme, the large excess of ubiquinone may(iii)non-phosphorylating electron-transport system,FIG. 2. Three possible schemes for the participation of ubiquinone (UQ) in theact as a source of reducing equivalents for some other process. Thirdly, thequinone may be placed on a branch pathway, linking the flavoproteins withthe antimycin A-sensitive factor.This would be in accord with the kineticmeasurements. In such a scheme the ubiquinone could be acting as aninterchain conductor or as an intermediate in oxidative phosphorylation.Most of the work on the enzymic function of ubiquinone has been doneon non-phosphorylating preparations. Experiments with intact phosphoryl-ating mitochondria have indicated that significant changes in the steady-state oxidation-reduction levels occur in the different metabolic states.These experiments will be discussed in the last section below.Oxidative Phosphory1ation.-The overall free-energy changes involved inthe oxidation of the substrates can be calculated from the standard oxid-ation-reduction potentials. The reduction of oxygen to water by DPNH,and succinate gives values of -51.9 and -39.7 kcal./mole, respectively.The number of ATP molecules formed per molecule of substrate oxidised(or P/O ratio) gives maximum experimental values of 3 for DPHN,-linkedsubstrates and 2 for succinate.The three sites of the phosphorylationappear to be between DPNH, and flavoprotein, between cytochromes band cl, and between cytochromes c and a.6The mechanism of oxidative phosphorylation is not yet understood, butsteady progress is being made in a several laboratories and a number ofworking hypotheses have been suggested. Basically, all these propose tha406 BIOLOGICAL CHEMISTRY.a carrier C couples with a molecule to form a high-energy intermediate whichin the presence of ADP and inorganic phosphate forms ATP.c+x+c.-x (2)A further property of the phosphorylating system is that of respiratorycontroL6BB If substrate is added to mitochondria in a medium containinginorganic phosphate there is a very slow oxygen uptake (resting or quiescentstate).On addition of ADP, however, rapid oxygen uptake is inducedimmediately (active state) and this continues until all the ADP has beenphosphorylated, the mitochondria then returning to the quiescent state.Experiments have shown that ADP does not activate electron transfer, butthat it reverses an inhibition of respiration. The control mechanism prob-ably operates in vivo to regulate the ATP supply of the organisms. Chancehas identified spectrophotometrically three sites of inhibition in the restingstate which he calls “ cross-over” points.6 These are between DPNH,and flavoprotein, cytochrome b and c, and cytochrome c and a.Theseare the sites of phosphorylation and Chance has suggested that a naturalinhibitor, I, inhibits electron transport in the quiescent state. Thus themechanism of oxidation phosphorylation can be written as follows :C - X + ADP + Pi C + X + ATP (3)cox. + I Cox.] (4)C0J + 2e -, CEd - I (5)Cred - I -/- x # c,+ x N I (6)X-l+Pp,=+=X-PP+I (7)In the absence of inorganic phosphate (Pi) or ADP the inhibited form ofthe carrier CoxJ builds up and electron transport slows down or stops.Uncoupling by 2,4-dinitrophenol is assumed to act by irreversible bindingof I:The natures of X and I are not known; it is possible that there are threedifferent 1’s corresponding to the three sites of phosphorylation.Lehninger’s group 40 have been working mainly with phosphorylatingsub-mitochondrial fragments prepared by treating rat-liver mitochondriawith digitonin.* Lehninger’s scheme for oxidative phosphorylation can bewritten :X - P + ADP-X+ ATP (8)X - I + DNP X + I.DNP (9)Electron t nnsfer c+x-c-x (10)C N X + P i - - c + x - P ( 1 1 )Instead of trying to identify the primary “ high-energy ” form of thethree specific respiratory carriers which are involved in the energy coupling,Lehninger has approached the problem from the “ back-door ” and has39 B.Chance, in Ciba Foundation Symposium on “The Regulation of Cell Meta-bolism,” Churchill, London, 1959.40 A. L.Lehninger, C. L. Wadkins, C. Cooper, T. M. Devlin, and J. L. Gamble,Sciewce, 1958, 128, 450.X-P+ADP - -X+ATP (12KEDFEARN : ELECTRON TRANSPORT AND OXIDATIVE PHOSPHORYLATION. 407investigated the terminal reactions leading to the formation of ATP througha transphosphorylation to ADP. In the absence of net electron transferthe submitochondrial fragments bring about three characteristic trans-formations of ATP. These are : (i) adenosine triphosphatase activity,activated by 2,4-&nitrophenol; (ii) an ATP-Pi exchange reaction, inhibitedby dinitrophenol and azide, and ADP-dependent; and (iii) an ATP-ADPexchange reaction, inhibited by dinitrophenol but not by azide, and with itsrate not modified by presence or concentration of inorganic phosphate.These three processes appear to be manifestations of a sequence of reactionsas shown above.The ATP-Pi exchange is the sum of reactions (11) and(12), the ATP-ase activity is the sequence of reactions (12) and (ll), followedby hydrolytic breakdown of C - X with liberation of inorganic phosphate,and the ATP-ADP exchange is represented by reaction (12). It has alsobeen established that the high-energy complex is formed with the carrier inthe oxidised state. Thus the reaction leading to the complex is analogousto substrate-level phosphorylation in which energy-conservation occurs inan oxidative reaction. These findings are, however, contrary to those ofChance who claims that the high-energy complex is formed with the reducedcarrier.Slater’s group 41, 42 have proposed a mechanism of oxidative phosphoryl-ation very similar to that of Chance and his colleagues except that the inter-mediate, I (not an inhibitor in the sense used by Chance), forms a high-energyintermediate with the oxidised form of the carrier.The energy is trans-ferred to a second hypothetical compound, X, giving X - I. For respir-ation and ATP synthesis to continue, X and I must be re-formed in reactionsinvolving inorganic phosphate and ADP. This provides a control mechan-ism regulating the rate of ATP formation according to the energy needs ofthe cells. The same group of workers have shown that there are fourdifferent DNP-sensitive enzymes with ATPase activity and they suggestthat three of them are intimately concerned with the three phosphorylationreactions.These results, however, have been criticised by Chance andConrad 43 who claim that the identification of the phosphorylation sites bythe determination of pH optima is not feasible at the present time.Naturally Occurring Coupling and Uncoupling Factors.-As alreadypointed out, mitochondria possess the property of respiratory control inaddition to the ability to synthesis ATP. It has been shown that the twoprocesses are di~sociable.~~ Thus loss of respiratory control is not necessarilyaccompanied by a loss of phosphorylation efficiency. Uncoupling agentshave a differential effect on the two processes. Thus 4-hydroxy-3,5-di-iodo-benzoate (DIB) can bring about an almost complete loss of respiratory con-trol without having much effect on the P/O ratio. Further, mitochondriain a magnesium-deficient medium have low respiratory control ratio buthigh P/O ratios. However, addition of magnesium ions restores respiratorycontrol.41 E. C. Slater, in Proc. Internat. Symp. on Enzyme Chemistry, Tokyo and Kyoto,1957, Pergamon Press, London, 1958.42 E. C. Slater and W. C. Hiilsmann, in Ciba Foundation Symposium on “ The Regul-ation of Cell Metabolism,” Churchill, London, 1959.43 B. Chance and H. Conrad, J . Biol. Chew., 1959, 234, 1568408 BIOLOGICAL CHEMISTRY.Recently, several naturally occurring controlling factors in mitochondriahave been recognised. Pullman et aLM have described a soluble heat-labilenon-dialysable fraction isolated from disrupted mitochondria which, whenadded to submitochondrial fragments, restores the P/O ratio. Anotherfactor, this time heat-stable, which stimulates oxidative phosphorylation,has been isolated from the soluble fraction after the treatment of mito-chondria with ultra~ound.~~ The activity of this substance is paralleled bythat of coenzyme A.The presence of an endogenous uncoupling factor in aged mitochondriahas been demonstrated. This substance was shown to have the spectrumof a hzm compound and was named " mitochrome." 46 Hulsmann et ~1.4'447have now shown that the uncoupling factor could be separated from thehaem compound by extraction with iso-octane. It is postulated that thefactor is a lipid (possibly an unsaturated fatty acid) which was originallybound to a cytochrome but is liberated when the cytochrome is convertedinto mitochrome. Bovine serum albumin, which restores phosphorylationin aged mitochondria, probably acts by binding the uncoupling factor.An interesting soluble mitochondrial protein named R factor has beenisolated from mitochondria treated with ultrasound.& This factor has beenshown to abolish respiratory control in mitochondria without affectingphosphorylation ; in high concentrations it also uncouples phosphorylation.R factor may be a mixture, because different preparations vary in theiruncoupling and " respiration-releasing '' activities.An extra-mitochondria1 uncoupling factor which is of major physiologicalimportance is thyroxine. This has been shown to be a potent uncouplingfactor in intact mitochondria; it causes swelling, possibly by an interactionwith a bound form of DPN. It does not have any action on mitochondrialfragments.48 Iuz vivo, thyroxine may act on the respiratory control mechan-ism. Hoch and Lipmann 49 found that mitochondria isolated from livers ofhyperthyroid rats have normal P/O ratios but are loosely coupled; i.e.,they respire at a high rate in the absence of a phosphate-acceptor system.(&inones in Oxidative Phosphory1ation.-Martius and his group 60 putforward evidence that vitamin K is a functional component of the respiratorychain. They suggested that vitamin K, was a hydrogen carrier, mediatingthe reaction between DPNH, and cytochrome b in a phosphorylating path-way, while the reaction through the flavoprotein represented a non-phos-phorylating pathway. Experiments carried out by Colpa-Boonstra andSlater 51 on Keilin-Hartree preparations using menadione (vitamin K3)showed that this substance did not act as a hydrogen carrier between44 M. E. Pullman, H. Penefsky, and E. Racker, Arch. Biochem. Biofihys., 1958, 76,45 W. C. McMurray and H. A. Lardy, J . Bid. Chem., 1958, 233, 754.46 B. D. Polis and H. W. Shmukler, J. Bid. Chem., 1957, 227, 419.47 W. C. Hulsmann, W. B. Elliot, and H. Rudney, Biochtim. Biophys. Actu, 1958,48 A. L. Lehninger, C. L. Wadkins, and L. F. Remmert, in Ciba Foundation Sym-49 F. L. Hoch and F. Lipmann, Proc. Nat. Acad. Sci. U.S.A., 1954, 40, 909.50 C. Martius and D. Nitz-Litzow, Biochim. Biophys. Acta, 1954, 18, 162, 288.51 J. P. Colpa-Boonstra and E. C. Slater, Biochinz. Biophys. Acta, 1968, !27, 122.227.27, 664.posium on " The Regulation of Cell Metabolism," Churchill, London, 1959REDFEARN : ELECTRON TRANSPORT AND OXIDATIVE PHOSPHORYLATION. 409DPNH, and cytochrome b. Furthermore, Martius’s hypothesis was weak-ened by the fact that vitamin K could not be detected spectroscopically inmitochondria1 preparation^.^^^^^Recent experiments involving a new technique have, however, providedfurther support for the participation of vitamin K in oxidative phosphoryl-ation. When rat-liver mitochondria are exposed to ultraviolet light theP/O ratios for the oxidation of P-hydroxybutyrate and succinate are de-pressed. Restoration of the P/O ratio with succinate was achieved byadding cytochrome c to the reaction mixture while that of the DPN-linkedsubstrates required both cytochrome c and vitamin K,.% Thus it seemed asif vitamin K, could replace a factor at the first site of oxidative phosphoryl-ation which had been destroyed or inactivated by the ultraviolet light.The facts that vitamin K is rapidly destroyed by ultraviolet light and that thereactivation is specific for vitamin K, support the hypothesis that the vitaminor a very closely related substance is an essential functional component ofthe oxidative phosphorylation system. However, the inability to detectvitamin K, or any closely related compound in mitochondria makes it diffi-cult to accept this hypothesis unreservedly.The possibility that ubiquinone may be intimately concerned in oxidativephosphorylation is being actively investigated. Oxidation-reduction of theendogenous quinone in intact mitochondria has been studied by Hatefi,Chance, and Redfearn and Pumphrey.54 These authors have shown thatthe changes in the steady-state oxidation-reduction levels in the variousmetabolic states are consistent with those of the other respiratory chaincarriers, but at the moment there is no evidence for its direct participationas an intermediate in oxidative phosphorylation.The work on vitamin K and ubiquinone has stimulated the productionof a number of theoretical schemes for the participation of quinones inoxidative pho~phorylation.~~E. R. R.J. N. DAVIDSON.T. W. GOODWIN.H. MCILWAIN.E. R. REDFEARN.R. WHITTAM.58 E. R. Redfearn and A. M. Pumphrey, unpublished work.69 W. A. Anderson and R. D. Dallam, J. Bid. Chew., 1959, 234, 1959; R. E. Beyer,ibid., 1959, 234, 688.64 Y. Hatefi, Biochinz. Biophys. Ada, 1959, 31, 502; B. Chance, in Ciba Found-ation Symposium on “ Quinones in Electron Transport,” Churchill, London, 1961 ;E. R. Redfearn and A. M. Pumphrey, Biochem. Biophys. Res., Comm., 1960,3,650.65 K. Harrison, Nature, 1959, 181, 1131; V. M. Clark, G. W. Kirby, and A. Todd.ibid., 1958, 181, 1650; I. Chmielewska, Biochim. Biophys. Acla, 1960, 39, 170

ISSN:0365-6217    

DOI:10.1039/AR9605700352

出版商:RSC    

年代:1960

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ANALYTICAL CHEMISTRY1. INTRODUCTIONPREVIOUS reporters have described 1*2*3 the difficulties of preparing anAnnual Report on analytical chemistry. There is now even more material.Chemical Abstracts for 1960 contains abstracts of over 5500 papers; Ana-lytical Chemistry’s review of two years’ fundamental developments inanalysis lists nearly 9000 references. Advances in the subject are to befound in a growing number of journals devoted to analytical chemistry ingeneral, analytical chemistry in particular, and applications of analysis tospecific fields of chemistry, as well as in more catholic journals in whichpapers of analytical importance find a place.Selection from this overabundance of material must be made; but anyselection must reflect the Reporters’ prejudices, to the inevitable disappoint-ment of some authors and readers. It may indeed lead to the exclusion ofwork destined to play a major part in the development of analyticalchemistry.Many of the revolutionary advances in the subject can betraced directly to discoveries made earlier, sometimes independently by anumber of workers, and awaiting a combination of need and enlighteneddevelopment for their acceptance. Such discoveries are seldom recognis-able as major ones from their inception: detailed study and applicationover a wide front and for a long time are more usually needed to establishtheir full possibilities and, equally important but often later to emerge, theirlimitations.In the assessment of worth, it is not even true that publication inone year of a great many papers on a particular method indicates its im-portance.Possibly it indicates a lack of fundamental information regardingthe method,2 or it may merely record the application, particularly in organicand biochemical analysis, of an established method to a host of slightlydiffering environments.Since selection is fraught with such difficulties, it is expedient to reduceit as far as possible. So, in order to give fuller attention to some develop-ments, others have been deferred to the next Report. Those omitted areelectrical methods in general, including electrodeposition, coulometry,polarography, radiochemistry, mass spectrometry, and instrumental endpoints in titrimetry.The arrangement of the Report is as follows; notwithstanding theomissions, much ruthless rejection of pertinent material has had to be made:(1) Introduction.(2) General. (3) Basic Operations and Apparatus.(4) Qualitative Analysis. (5) Methods of Separation. (6) Gravimetric and1 F. R. Cropper, Alan. Re@orts, 1950, 47, 373.2 C. L. Wilson, Ann. Reports, 1951, 48, 308.J. Haslam and D. C. M. Squirrell, Ann. Reports, 1957, 54, 353.Analyt. Chem., 1960, 32, No. 5CARTWRIGHT AND WILSON GENERAL. 41 1Titrimetric Analysis. (7) Determination of Elements in Organic Coni-pounds. (8) Spectroscopic Analysis. (9) Thermal Methods.2. GENERALTwo addresses of interest to analytical chemists generally have beenpublished. H. N. Wil~on,~ in “ The Changing Aspect of Chemical Analysis, ”surveys many present trends in analytical chemistry.He defines chemicalanalysis (rather than analytical chemistry) as a body of techniques, chemicaland physical, that are used to determine the composition of any substance,and he emphasises the economic aspects of speed, accuracy, and usefulnessof analyses. Information is nowadays wanted on new materials, andinformation on old materials is wanted more quickly. The author appliesthese requirements in a detailed and critical study of a number of chemicaland physical methods, pointing out, with examples, that the analyticalchemist needs more courage and skill in dropping some of his old methodsand reagents, and stressing the danger that standardising a method is oftena good way of stopping its development.P.J. Elving does not, in ‘‘ Organic Analysis: Art and Science,” confinehimself only to the organic field. He deals with the function and nature ofanalytical chemistry in general, and with the processes of its development.His definition of analytical chemistry is the scientific application of thechemical and physical properties of substances to their identification ,characterisation, and determination, and he is insistent that, however suc-cessful empirical methods may be, they are no substitute for scientificallybased and clearly understood developments. He gives a penetrating surveyof the scope and achievements of organic analysis, including analyticalresearch and the problems of scale and instrumentation. Both authorscomment briefly, and somewhat destructively, on the teaching of analyticalchemistry.In a more limited field, C.D. Susano gives an account of the r61e of theanalytical chemist in nuclear reactor technology, indicating the dual require-ments of new and better methods of analysis of a very wide variety ofmateriak, and the further development of automatic and remote analyticalcontrol of hazardous products.Analysts interested in the historical development of their subject willwelcome the attention drawn by C. Duva18 to the 17th and 18th centuryorigins of a number of analytical tests and techniques.The introduction of a new mass unit, the “ Emich,” denoting 10-15 g., isproposed by F. L. Hahn9 in order to extend definition of scales of work,with the usual prefixes, even down to molecular and atomic quantities;this has received support and comment.l* Hahn also advocates the defini-tion of sensitivity and volume of test solution, in the evaluation of colourH.N. Wilson, Analyst, 1960, 85, 540.P. J. Elving, Analyt. Chem., 1960, 32, 1538.C. D. Susano, Talanta, 1960, 6, iii.* C. Duval, Mikrochim. Acta, 1960, 630.F. L. Hahn, Mikrochtim. Acta, 1960, 650.lo A. A. Benedetti-Pichler, Mikrochim. A cta, 1960, 660412 ANALYTICAL CHEMISTRY.tests, by the negative logarithms of the limiting concentration and the limitof identification. The nomenclature of complexing agents and of titrationsinvolving them has been discussed.11J2Reviewing instrumentation in analysis, R. H. Miiller l3 combines ageneral survey of the advantages of transistors (reduction of space, warm-up time, and need for ventilation), of new reference standards of e.m.f.(adaptability and negligible temperature coefficient), and of new types oftransducer (faster and more sensitive measurement of displacement, coupledif necessary to digital presentation of data) with particulars of a selectionof devices which could be applied to a variety of instrumental problems inanalysis.Hal& and Schneider l4 describe a non-electronic integrator withdigital presentation applicable to rapidly changing variables.A review by Nelson15 of statistical methods in chemistry refers to anumber of applications of potential value to the analyst, as well as to somedirectly concerned with interlaboratory comparisons of methods.Reviews covering more than one method of analysis, and papers com-paring various methods for particular determinations, are considered next.Progress in thirty methods of analysis is surveyed in the biennial issueof Analytical Chemistry devoted to fundamental developments in analysis.Summaries have been published16 of papers presented at a symposium ofthe Analytical Division of the A.C.S.on trace analysis. They deal withX-ray spectrography, radio-activation analysis, emission spectroscopy,electrochemical methods, and gas chromatography. Rodden 17 surveyschemical, spectrographic, and isotopic standards in the field of nuclearenergy. In a review of light-scattering methods for the chemical character-isation of polymers, Peaker l8 deals with the applications and interpretationof turbidimetric titrations and light-scattering measurements.Methods ofseparating and determining vitamin B,, are reviewed by Shaw and Bessell.19The identification and determination of organo-silicon compounds , particu-larly silanes and siloxanes, are reviewed by J. C. B. Smith.20 Reviews havealso appeared on progress in analytical chemistry in general,21 on ultramicro-analysis,22 and on toxicological Progress in organic functionalgroup analysis is reviewed by T. S. Ma.24Milner and Edwards% have given a comprehensive review, with 139references, of the analytical chemistry of zirconium. They deal with theapplications and limitations of separation by precipitation, ion exchange,11 Analyt.Chim. Acta, 1960, 22, 300.12 F. Bermejo, J. Barcel6, A. Prieto, and A. Badrinas, Analyt. Chim. Acta, 1960,23, 500; A. M. G. Macdonald, ibid., 1960, 23, 502.13 R. H. Muller, Analyt. Chem., 1960, 32, 6 3 ~ .14 I. HalAsz and W. Schneider, 2. analyt. Chem., 1960, 175, 94.15 B. N. Nelson, Analyt. Chem., 1960, 32, 1 6 1 ~ .16 W. W. Brandt, Analyt. Chem., 1960, 32, 1595.17 C. J. Rodden, Talanta, 1960, 6, 3.18 F. W. Peaker, Analyst, 1960, 85, 235.19 W, H. C . Shaw and C . J. Bessell, Analyst, 1960, 85, 389.20 J. C. B. Smith, Analyst, 1960, 85, 465.2 1 I. P. Alimarin, Chem. Listy, 1960, 54, 462.22 M. Ordogh, Magyar Kbm. Lapja, 1960, 15, 325.23 A. S. Curry, J . Pharm. Pharmacol., 1960, 12, 321.24 T. S. Ma, Microchem. J., 1960, 4, 373.25 G.W. C. Milner and J. W. Edwards, A~zalyst, 1960, 85, 86CARTWRIGHT AND WILSON: BASIC OPERATIONS AND APPARATUS. 413solvent extraction, and chromatography, and of determination by gravi-metric, t itrimet ric, absorptiometric, and miscellaneous met hods, includingradioactivation. Various methods of determining traces of zinc in thepresence of a wide variety of metallic impurities have been compared 26 byusing radio-zinc, and solvent extraction with dithizone in the presence ofdiethyldithiocarbamate as a masking agent is recommended, followed byspectrophotometric determination. Solvent extraction is also applied tothe determination of uranium in sea and isotope dilution and fluori-metry are compared with pulse polarography for this determination.Beamish 28 gives a full and critical review, with 157 references, of old andnew methods of isolating and separating the platinum metals.In aninvestigation into the corrosion products of aluminium under variouscondition^,^^ many chemical and physical methods of examination wereused, including X-ray diffraction and fluorescence, differential thermalanalysis, and electrographic, spectrographic, and microscopical methods.3. BASIC OPERATIONS AND APPARATUS- The operations and apparatus considered here are those common tomany analytical methods.Chemical and physical properties of six types of glassware used in analysishave been reported.30 The availability of expendable plastic beakers andmetal dishes is a development in which the biochemist has led the way.The development, operation, and principles of automatic and con-tinuously-recording balances have been reviewed s with 165 references.They are not only of use in thermogravimetric studies: a list of generalapplications is given. Both null-point and deflection instruments aredescribed, which use mechanical, optical, electrical, and electronic means ofmeasurement, restoration, or recording.Lincoln 32 describes an automaticrecording electromagnetic balance with a range of 0-100 mg. and a pre-cision of 0.04 mg. A non-automatic electro-microbalance with a capacityof 1.5 mg. and a sensitivity of about 1 pg., for weighing fibres, is describedby Morgan.= Tests have been carried out on three types of microbalancemounting; 34 it is shown that while a rigid mount has little effect onvibrations, indiscriminate use of resilient material can amplify them.Properly selected springs can absorb all but very low-frequency vibration,and bolting the balance to the mount appears to be an advantage.Handling of moisture- or oxygen-sensitive materials can be carried outin a nitrogen-filled dry-box fitted for electrical sealing of the sample t ~ b e , ~ 5D.W. Margerum and F. Santacana, Analyt. Chem., 1960, 32, 1157.27 J. D. Wilson, R. K. Webster, G. W. C. Milner, G. A. Barnett, and A. A. Smales,2* F. E. Beamish, Talanta, 1960, 5, 1.z9 H. P. Godard and W. E. Cooke, Cor~osion, 1960, 16, 117.3" J. P. Williams, Microchem. J., 1960, 4, 187.31 S. Gordon and C. Campbell, Andyt. Chem., 1960, 32, 2 7 1 ~ .38 K.A. Lincoln, Rev. Sci. Instr., 1960, 31, 537.33 F. R. Morgan, J. Sci. Instr., 1960, 3'9, 53.34 E. Kissa, Microchem. J . , 1960, 4, 89.35 A. F. Williams and T. 0. Park, Analyst, 1960, 85, 126.Analyt. Chim. Acfa, 1960, 23, 505414 ANALYTICAL CHEMISTRY.or in a specially designed cylindrical vessel in a stream of argon or nitrogen,a weighing bottle being used with a long-stemmed stopper.36 The weighingof small samples of volatile liquids is improved by using a weighing capillaryfitted with a fine platinum wire to retain the liquid in the middle, minimisinglosses by diffusion of vapo~r.~' Amendments have been published to BritishStandards: tables for use in the calibration of volumetric glas~ware,~8density bottles ,39 and graduated measuring cylinders.40 The AmericanChemical Society recommends specifications for microchemical pipettesof the Folin, wash-out, and weighing types.To hasten routine analyses,pipettes and measuring vessels which can be rapidly filled by suction havebeen devised.42For highlypure aluminium Houpt and Winia 43 advocate hydrochloric acid and a fewdrops of cupric chloride solution, with the addition of hydrogen peroxidesolution during the dissolution. Where copper is undesirable, hydrochloricacid is effective if it is in contact with, e.g., platinum or gold, and a fewdrops of hydrogen peroxide solution are added as a depolariser. For refrac-tory materials, Feldman 44 employs fusion with ammonium hydrogen sul-phate instead of potassium pyrosulphate.Although it is not so effectivewith some materials, it can be kept molten under a tightly-fitting watch-glass indefinitely at 475"; it boils gently without solidification at highertemperatures, but it will vaporise smoothly and completely in the open at200-300". It does not attack platinum at low temperatures; at highertemperatures it can be used in quartz vessels. For some sodium peroxidefusions, zirconium crucibles are recommended.& Siliceous materials aredecomposed, for determination of silica, by sintering with sodium peroxide ,46followed by extraction with water and with sulphuric acid, and excess ofperoxide is destroyed by permanganate. Nitrogen in rocks and silicateminerals can be determined 47 after a sealed-tube digestion with sulphuricacid for l-lh hours at 420".General problems of sample preparation in micro-analysis are discussedby Schulek and La~zlovszky.~~ Reagents for reduction, oxidation , fusion,and saponification are recommended, and methods of concentrating traceelements are described.The Analytical Methods Committee of the Society for AnalyticalChemistry have published a comprehensive report 49 on the destruction oforganic matter. Methods of wet and dry decomposition are recommended,The dissolution of difficult materials has received attention.a6 T.Niedermaier, 2. analyt. Chem., 1960, 174, 407.37 Tetsuo Mitsui and Chieko Furuki, Mikrochim. Acta, 1960, 169.38 B.S. 1797 : 1952. Amendment No. 2.39 B.S. 733 : 1952. Amendment No. 2.40 B.S. 604: 1952.Amendment No. 4.4 1 See Analyt. Chem., 1960, 32, 1045.4 2 G. Lindley, Lab. Practice, 1960, 9, 40, 111.43 P. M. Houpt and R. A. F. Winia, Analyst, 1960, 85, 924.44 C. Feldman, Analyt. Chem., 1960, 32, 1727.45 R. P. Anibal, Analyt. Chem., 1960, 32, 293.46 C. B. Belcher and L. B. Skelton, AnaZyt. Chim. Acta, 1960, 22, 567.A7 F. J. Stevenson, Analyt. Chem., 1960, 32, 1704.48 E. Schulek and J. Laszlovszky, Mikrochim. Acta, 1960, 485.49 Analyst, 1960, $5, 643CARTWRIGHT AND WILSON : BASIC OPERATIONS AND APPARATUS. 415with their application t o particular types of organic materials, and notes ofthe advantages, disadvantages, and, where appropriate, possible hazards ofeach method. Special procedures are advocated when mercury is to bedetermined.In addition to general discussion, detailed procedures aregiven for nine methods of wet decomposition and six methods of dry decom-position. Particularly for the destruction of large organic molecules, aswith cellulose, wool, sugars, leathers, coal, and polymers, G. F. Smith andH. Diehl 5O recommend substituting periodic for nitric acid in their perchloric-nitric " liquid fire reaction." Lower temperatures and less concentratedperchloric acid solutions are required, giving better control of reaction rate.Rapid wet-oxidation procedures have been described for biologicalmaterial^,^^ petroleum and explosive^.^^ Hatcher reports that wetdigestion of plant materials can cause serious loss of boron. A study oferrors arising from the alkaline ashing of serum in determination of protein-bound iodine has resulted in a modified method.55For the determination of water and carbon dioxide in silicate rocks, aclosed system has been devised56 for recycling the dried air, giving lowerblanks.A drying apparatus for determining moisture in organic com-pounds 57 employs a conducting-surface tube for heating, and a double-ended weighing bottle to obviate loss by electrostatic " jumping." A rapidmethod of determining water in magnesium perchlorate 58 may have applic-ation to other desiccants; the water content is related to the increase intemperature on dissolving the sample under carefully controlled conditions.For magnesium perchlorate containing 5% of water there is an increase ofabout 30". Methods which employ the freezing of carbon dioxide under lowpressure in a liquid-air trap can be upset by condensation of the oxygen gasstream; this can be overcome by using a modified absorber and procedure.59Advantages of a magnetically agitated Van Slyke apparatus are described.60An investigation into saturated salt solutions for use in static control ofrelative humidity has led to recommendations 61 of systems which have lowtemperature coefficients, and systems which provide a wide range of humidi-ties at specified temperatures using relatively few salts.Miscellaneous apparatus of interest include : a continuous extractionfor use with ethanol under reduced pressure,62 a centrifugal filtration appara-tus where the filtering surface is a ground-glass joint between a bulb andthe mouth of a flask,63 a preheating automatic self-cleaning water sti11,M50 G.F. Smith and H. Diehl, Talanta, 1960, 4, 185.51 L. L. Reitz, W. H. Smith, and M. P. Plumlee, Analyt. Chem., 1960, 32, 1728.52 J. S. Forrester and J. L. Jones, Analyt. Chem., 1960, 32, 1443.53 R. N. Rogers, Analyt. Chem., 1960, 32, 1050.54 J. T. Hatcher, Analyt. Chem., 1960, 32, 726.55 0. P. Foss, L. V. Hankes, and D. D. Van Slyke, Clinica Chim. Acta, 1960,56 P. G. Jeffery and A. D. Wilson, Analyst, 1960, 85, 749.57 A. C. Thomas, Analyst, 1960, 85, 771.jS G. F. Smith, Talanta, 1960, 5, 189.51) V. Ramakrishna, Analyt. Chim. Acta, 1960, 22, 592.Go Lab. Practice, 1960, 9, 93.63 A. S. Curry and S. E. Phang, J . Pharm. Pharmacol., 1960, 12, 437.G3 E.L. Anderson, AnaZyst, 1960, 85, 228.G4 E. Bishop and J. R. B. Sutton, Analyt. Chim. Acta, 1960, 22, 590.5, 301.L. B. Rockland, Analyt. Chena., 1960, 32, 1375416 ANALYTICAL CHEMISTRY.and a multiple-bank still for determination of fluorine in plant samples.65An automatic level control for a liquefied gas is described,66 which dependson the temperature effect on an enclosed propane sample.4. QUALITATIVE ANALYSISInorganic.-Emphasis on schematic qualitative analysis, except as adiscipline, continues to decline as the versatility of instrumental methods ofdetection increases. A scheme for the chromatographic separation andidentification of 24 common anions on paper strips has been evolved.67Ethanol-pyridine-ammonia eluant is used, and the anions are identified byreagent sprays.Another chromatographic scheme,68 on calcium sulphatesticks, permits separation and identification of pairs of closely relatedanions. Factors influencing the stability and use of hydrogen sulphide dis-solved in acetone for precipitation have been studied.6BThe idea of a specific test for each element is no longer seriously enter-tained; but the work done to produce more sensitive and more selectivereagents is of the utmost value, particularly if it is so thoroughly done as toleave no doubt about the mechanism, potentialities, and limitations of thereaction. Such work, as well as having value in the qualitative sphere, canbe the basis of a new quantitative chemistry, for behind every new spot testis the possibility of better gravimetric, titrimetric, or spectrophotometricmethods.Afew general methods are considered first, followed by identification tests forindividual elements or small groups of elements, arranged in order of thePeriodic Classification.The versatility of metal-pyridine-thiocyanate formation in qualitativeanalysis has been illustrated.'* The extraction of the compound intochloroform affords a quick method of identifying bivalent copper, nickel,cobalt, iron, and manganese. The copper-pyridine compound can similarlybe used to identify thiocyanate and some other anions, and the copperpotassium thiocyanate compound to identify pyridine and to differentiatetertiary from primary and secondary amines. The ring-oven method hasbeen used in trace-metal identifi~ation,~~ in analysis of particulate matter inair,72 and in enhancing the sensitivity of s p ~ t - t e s t s .~ ~ For collecting tracesof material from antiques, and for obtaining samples of ores and minerals,the use of a small corundum rod is advocated; 74 its use in the subsequentidentification of lead is described.The alkali metals give few colour reactions: oneThis is already evident in some of the tests described below.Main group elements.G5 R. F. Brewer and G. F. Liebig, jun., Analyt. Chem., 1960, 32, 1373.66 V. E. Schupbach, AnaZyt. Chem., 1960, 32, 1536.67 I. I. M. Elbeih and M. A. Abou-Elnaga, AnaZyt. Chim. Acta, 1960, 23, 30.68 B. N. Sen, Analyt. Chirn. Acta, 1960, 23, 152.6o W. I. Stephen, Mikrochim.Acta, 1960, 927.'1 G. Ackermann, Mikrochim. Ada, 1960, 771.7 1 P. W. West, H. Weisz, G. C. Gaeke, jun., and G. Lyles, Analyt. Chem., 1960, 32,7 9 H. Weisz and P. W. West, Mikrochim. Acta, 1960, 584.i4 H. Ballczo, Mikrockim. Acta, 1900, 973.G. H. Ayres and S. S. Baird, Analyt. Chim. Acta, 1960, 23, 446.943CARTWRIGHT AND WILSON QUALITATIVE ANALYSIS. 417is described which can be used for spectrophotometric determination ofsodium and potassium, and, less satisfactorily, lithium. It appears to bevery specific for the alkali metals, only tertiary amines (for the identificationof which the test is normally used) interfering, although the colow can beinhibited by some ions. An intense violet-red colour is formed when anacetic anhydride solution of the sample is added to citric acid dissolved in2,4-pentanedione, toluene is added, and the mixture is warmed.76 1,2-Di-aminocyclohexane-NNN'N'-tetra-acetic acid has been recommended forthe detection and complexometric titration of calcium 76 in the presence ofother alkaline-earth metals and magnesium: it has been named Calci-chrome (CDTA), and its preparation is described.Traces of gallium inaluminium can be detected 77 by precipitation on titanium hydroxide andextraction of the alizarin lake into ether from an alkaline buffer.A sensitive method for the detection and rough estimation of carbonmonoxide in the atmosphere 78 depends on the acceleration of reduction togold of gold chloride solution by arsenious oxide in the presence of carbonmonoxide: the test is adapted for use on filter paper.Tin can be identifiedin tungsten minerals with toluene-3,4-dithiol if tungsten is masked bycitric acid, and the molybdenum complex is extracted with light petroleum.Trace amounts of nitrous acid 8* give a violet colour, insoluble in a numberof organic solvents, with amidopyrine and acetic acid. The reaction isrelatively free from interferences. Trace amounts of orthophosphate inbiological materials can be detected 81 by modifying a titrimetric method,involving quinoline molybdate, for use as a spot test. Under optimumconditions 1.5 xElementary sulphur can be identified,82 if necessary after extraction withethanol, by formation of polysulphide with sodium sulphide and reactionwith acetone to give a blue colour; neither thiocyanate nor thiosulphateinterferes.A range of thio-compounds, as well as cyanide and iodide, givea colour reaction with mercurated phenolphthalein; and some such com-pounds quench the fluorescence of mercurated fluorescein. Both reactionscan be useds3 for identification purposes. Selenium can be detected asselenate with +-ethoxychrysoidine,s4 and estimated by the time taken forthe colour to change from red to yellow. Conditions for maximum sensitivityof the sulphur dioxide reduction test for selenous acid have been studied.85A spot test for fluoride 86 is based on the blue-black reaction with silverof rhodizonic acid liberated from ferric rhodizonate by fluoride ions; inter-ference by oxalate can be suppressed by barium, but sulphide must beabsent.Microscopic examination of their reaction products with leadg. of phosphorus can be detected in 2 pl. of solution.i i F. E. Critchfield and J. B. Johnson, Talanta, 1960, 5, 58.76 R. A. Close and T. S. West, Talanta, 1960, 5, 221.77 V. K. Kuznetsova and N. A. Tananaev, Zhur. analit. Khirn., 1960, 15, 240.78 P. Paulin, Bull. SOC. chim. France, 1959, 1845.79 P. G. Jeffery, Rec. Geol. Surv. Uganda. 1955-56 (publ. 1959), 43.8o W. Wawrzyczek, Nature, 1960, 186, 883.R. Antoszewski and J. S. Knypl, Analyst, 1960, 85, 527.G. Ingram and B. A. Toms, Analyst, 1960, 85, 766.8s M. Wronski, 2. analyt. Chem., 1960, 175, 432.y4 L. Barcza and E. Schulek, Mikrochim. Actu, 1960, 261.95 E. R. Caley and C.L. Henderson, AnaZyt. Chem., 1960, 32, 975.86 H. Weisz, Mikrochim. Ada, 1960, 703.REP.-VOL. LVII 418 ANALYTICAL CHEMISTRY.chloride serves to identify fluoride-containing particles in the air; 87 sul-phate and phosphate can be distinguished and do not interfere. Iodinecan be distinguished from chlorine and bromine by its formation of anacetate ester with peroxyacetic acid; 88 the ester is detected by its reactionwith hydroxylamine followed by ferric chloride to give a wine-red colour.Small concentrations of periodate can be detected in the presence of iodateby its violet fluorescence with luminol and hydrogen per0xide.8~Transition elements. The uses and limitations of X-ray fluorescence fordetection, down to 0.01 or O.OOl%, of elements of greater atomic numberthan sodium have been described.g0 The method is rapid and does notconsume the sample ; it is particularly useful for distinguishing betweenclosely related transition elements.Copper may be detected, but not in the presence of nickel, ferric, orvanadyl ions, by formation of a bright blue complex with 1,2diaminocycIo-hexanetetra-acetic acid between pH 4.5 and lZgl The best conditions forthe microscopic identification of copper with picrolonic acid have beenstudied,92 and have made possible identification down toSpot tests for silver and for gold are reported,93 based on their catalyticaction on the decomposition of ferrocyanide in the presence of nitroso-benzene, giving a violet colour, with a lower limit of detection in one drop of0.004 pg.for silver and 0.05 pg. for gold. Mercury, palladium, and a numberof aromatic nitroso-compounds also react, but iodide will mask the inter-ference from mercury, and also from silver in testing for gold. A number ofother ions reduce the sensitivity, and the test is affected by sunlight.Cadmium may be identified by microscopic examination of the crystalsproduced by pyrimidine in the presence of sodium chloride or hydrochlorica~id.~4 Of the common cations, many give white precipitates, but onlymercury gives a grey precipitate, with potassium antimony1 tartrate.95Both cupric and cerous ions give a blue complex with BromopyrogallolRed at pH 7.2. Copper can be distinguished with sulphide, enabling the testto be used for cerium in tissues.g6In the firstJg7 ammon-ium thiocyanate is added to the slightly acid ferric solution covered with alayer of ether, and the mixture is shaken in a closed flask.A reagent papercarrying a small fleck of freshly prepared potassium zinc ferrocyanide ishung in the ether, and in the presence of iron the fleck turns blue. Thesecond test 98 is based on the reaction between the ferrous ion (reduced by,g . or less.Two sensitive tests for iron have been described.B. J . Tufts, Anulyt. Chim. Acta, 1960, 23, 209.88 J. G. Sharefkin and H. E. Schwerz, Analyt. Chem., 1960, 82, 996.89 A. Berka, Coll. Czech. Chem. Comm., 1960, 25, 1224.90 C. Raimbault and G. Baron, Chim. analyt., 1960, 42, 336; G. Baron. J. Favre,91 F. B. Martinez and M.G. Abella, 2. unalyt. Chem., 1960, 174, 411.92 E. Wiesenberger, Mikrochim. Acta, 1960, 946.93 I. Kraljit, Croat. Chem. Acta, 1960, 32, 43; Analyt. Chim. Acta, 1960, 23, 514.ga J. C. B. Graf, Mikrochim. Acta, 1960, 902.os E. Chinoporos, Analyt. Cham., 1960, 32, 1364.96 J. Fischer, V. FischerovA-BergerovB, and E. VaSAkovB, Pracovni Le'Ka?5slvi,s7 F. 1;. Hahn, Mikrochim. Ada, 1960, 675.98 K. L. hlallik and B. Sen, Analyt. Chim. Acta, 1960, 23, 225.and C. Raimbault, ibid., p. 388.1960, 12, 26CARTWRIGHT AND WILSON QUALITATIVE ANALYSIS. 419e.g. , ascorbic acid) and phenyl 2-pyridyl ketoxime to give a violet chelate onthe addition of ammonia solution. This test is virtually free from inter-ferences.Organic.-The detection of elements in organic compounds by classicalmethods has been surveyed.99 The use of a dispersion of sodium in tolueneor, preferably, a less volatile liquid 100 overcomes many of the difficulties ofthe sodium fusion test for elements.Simple preliminary tests are de-scribed lol for compounds which yield on pyrolysis water or ammonia;these products react with an admixed thio-compound to give hydrogensulphide, which is detected with lead acetate paper. A sensitive spot testfor nitrogen compounds in petroleum fractions lo2 involves spraying thesample spot on filter paper with tetracyanoethylene in benzene. Thecolours produced by many interfering compounds are destroyed by heatingat l l O o , but those due to nitrogen compounds persist and can be used semi-quantitatively.The pyrolytic oxidation of some chlorine- and sulphur-containing compounds by higher metallic oxides can be used,lm throughdetection of the chlorine, hydrogen chloride, or hydrogen sulphide produced,for classification of the Compounds. Some quinones, particularly 2,5-di-phenyl-l,4-benzoquinoneJ can be used in microscopic mixed fusions lOQ forthe identification of hydrocarbons.A great many colour reactions for classes of organic compounds, andfewer for individual compounds, are constantly being devised. Some ofthese are adapted from established reactions and their conditions are wellunderstood. Others have been thoroughly investigated, and the nature ofthe reactions, the reasons for interferences or suppressions, and the funda-mental requirements for maximum sensitivity or quantitative application,have been elucidated.There are, however, many in which at least a degreeof empiricism is evident. The analyst cannot afford to ignore them, but hecould wish in some cases that more had been done to establish their mechan-ism, and hence more clearly their scope and limitations.Olefins may be detected by reaction with ozone and hydrolysis to car-bony1 groupsJ105 or by Friedel-Crafts reaction,lo6 followed by detection with2,4-dinitrophenylhydrazine. Ether is identified by detecting, with copperacetate-benzidine acetate, the ether peroxide formed on heating; lo7 insome hydrocarbon solvents, and in carbon disulphide, the test works onlyif carbon tetrachloride or chloroform is present, probably owing to liberationof chlorine by the ether peroxide.Colour reactions, which can be used to differentiate individual compoundsby spectrophotometric study, have been devised for detecting some classesof compounds in the atmosphere.Fluorene derivatives108 can thus begg J , B. Njederl and J. A. Sozzi, Mikrochim. Acta, 1960, 693.loo J, Patrick and F. Schneider, Mikrochim. A&, 1960, 970.Io1 F. Feigl and J. R. Amaral, Mikrochim. Acta, 1960, 816.laa P. V. Peurifoy and M. Nager, Analyt. Clzem., 1960, 32, 1135.1°3 F. Feigl, D. Goldstein, and D. Haguenauer-Castro, Bec. Trav. chim., 1960, 7fl, 531.lo4 D. E. Laskowski, Analyt. Chem., 1960, 32, 1171.loB J. G. Sharefkin and A. Ribner, J. Chem. Educ., 1960, 37, 296.lo6 J. G. Sharefkin and T.Sulzberg, Analyt. Chem., 1960, 32, 993.Io7 F. Feigl, R. J. Amaral, and D. Haguenauer-Castro, Mikrochim. Ada, 1960, 821.lo* E. Sawicki, T. W. Stanley, and J. Noe, Analyt. Chem., 1960, 32, 816420 ANALYTICAL CHEMISTRY.identified by using 1 ,2-dinitrobenzene, inner-ring o-quinones lo9 with 3,4-di-methoxyaniline, and 1,4-naphthaquinones 110 (unless they contain anelectron-donor group in the 2-position) with 2-aminothiophenol. Similaridentification of aralkyl and dialkyl ketones ll1 and polynuclear diary1ketones 112 is possible.A versatile test, which can be used for the specific identification of anyof its reactants, results from the reaction between glycine or some of itssimple derivatives, alkyl chloroformates, and pyridine. A dark greencolour is produced, which turns red on standing or with excess of pyridine,and the conditions for its formation have been investigated.lnAldehydes can be detected by the red or pink colour on warming themwith a few crystals of indole suspended in hydrochloric acid."* They canbe detected and determined in polluted air with Z-hydrazinoben~othiazole,~~5and with the same reagent and 9-nitrobenzenediazonium fluoroborate.U6Glyoxal may be identified, or alternatively may be used to test for thereagents, by colours produced with 1,2-dianilinoethane, with 2,3-diamino-naphthalene, and with 2-aminothiophen01.l~~ A specific test for form-aldehyde and compounds which give it on pyrohydrolysis involves condens-ation with hydroxylamine to give formaldoxime, which is detected by analkaline solution of a manganous salt.l18Organic acids react with tetraphenylstibonium sulphate to form saltswhich can be isolated and have distinctive melting points.ll9Phenolic compounds can be detected and identified on paper chromato-grams by using commercially available stabilised diazonium salts of aromaticamines as sprays.Individual examples are widely used; a comprehensiveinvestigation using 30 such reagents has been made.120Easily oxidisable substances such as sugars, polyhydric compounds,phenols, and their ester derivatives can be detected by spotting them on topaper containing potassium periodatocuprate : 121 the brown colour givenby the reagent is bleached by the test drop. Methacrylate resins give a dis-tinctive blue colour, extractable with chloroform,122 on heating with concen-trated nitric acid, cooling, and adding water and zinc powder or sodiumnitrite.Alkyl halides can be detected and classified by converting them into thecorresponding nitroparaffins by using sodium nitrite in dimethylformamideor dimethyl sulphoxide ; the addition of sodium hydroxide, carbon tetra-chloride, and an acid gives a reddish colour with the primary, and a blue-lo9 E.Sawicki and W. Elbert, Analyt. Chim. Acta, 1960, 22, 448.E. Sawicki and W. C. Elbert, Analyt. Chim. Acta, 1960, 23, 205.111 E. Sawicki, J . Noe, and T. W. Stanley, Mikrochim. Acta, 1960, 286.112 T. W. Stanley, Chemist-Analyst, 1960, 49, 47.113 R. L. Sublett and J. P. Jewell, Analyt. Chem., 1960, 32, 1841.114 V.Anger and G. Fischer, Mikrochim. Acta, 1960, 592.115 E. Sawicki and T. R. Hauser. Analyt. Chem., 1960, 32, 1434.116 E. Sawicki and T. W. Stanley, Mikrochim. Acta, 1960, 510.l 1 7 E. Sawicki and W. C. Elbert, Talanta, 1960, 5, 63.11s E. Jungreis, Chemist-Analyst, 1960, 49, 14.l1@ H. E. Affsprung and H. E. May, Analyt. Chem., 1960, 32, 1164.120 I. A. Pearl and P. F. McCoy, Analyt. Chem., 1960, 32, 1407.121 T. G. Bonner, Chem. and Ind., 1960, 345.122 E. B. Mano, Analyt. Chem., 1960, 32, 291CARTWRIGHT AND WILSON : QUALITATIVE ANALYSIS. 421green colour with the secondary compounds.123 Alkyl halides and dihalidescan be characterised by refluxing them with ethylenethiourea in n-propanolto form their 2-alkylthio-4,5-dihydroglyoxalinium salts, and from these thecorresponding free bases and their picrates.Identification data are givenfor all three types of derivative for a wide range of halides and dihalides.12*A sensitive test for primary alkyl halideslZ5 involves heating them at 100"with sodium thiosulphate, decomposing the product by heating further to160-180", and detecting the sulphur dioxide evolved. Carbonyl chloride,in concentrations in air down to 0.3 vg. per litre, can be detected by its purpleor red colour with paper soaked in anabasine or a mixture with relatedalkaloids.126Various nitrobenzene derivatives will oxidise diphenylbenzidine in thepresence of Devarda's aIl0y.1~~ The resulting blue colour can be used toidentify and differentiate related nitro-compounds.Spot-test detection anddifferentiation of o- and p-nitrophenol is described: 128 on heating the formerin a small test tube closed by filter paper moistened with dilute sodiumhydroxide or sulphide solution, a yellow or orange colour is produced; thelatter, on heating with hydrated sodium thiosulphate, dissolving the melt inwater and shaking with benzene, gives a yellow aqueous layer. An improvedmethod for detecting and differentiating the mononitrotoluenes 129 consistsof reduction to the nitroso-compounds by boiling with zinc and calciumchloride, filtering, and adding fresh trisodium pentacyanoamminoferratesolution. The resulting colours differentiate between o-, m-, and &nitro-toluenes, although nitrobenzene, 2,4-dinitrotoluene, and 2,4,6-trinitrotoluenegive similar colours and must be separately tested for.Most amines give easily-crystallised salts with dibenzofuran-2-sulphonicacid; the crystalline forms and melting points of the salts of 31 amines aredescribed.lm Aromatic amines, but not other nitrogen-containing com-pounds, give highly-coloured oxidation products with ceric salts in a varietyof organic solvents; 131 the colours and their changes on warming can incertain cases be used, with the data given, to identify individual amines andto distinguish between isomers.Diphenylamine and its derivatives, andalso carbazole and its derivatives, give a blue colour 132 on warming withhydrated oxalic acid first to 160" and then to 180-190". Phenylenediamineisomers can be rapidly distinguished by their reaction with molybdo-phosphoric acid to give colours which depend on the relative positions of thearnino-gr~ups.~~~ The same reagent will distinguish, by colour and crystalform, between a number of diazine~.l~~A comparison of tests for amino-acids on chromatograms has been made,lZ3 R.L. Dannley and F. V. Kitko, Analyt. Cheun., 1960, 32, 1682.lZp R. N. Boyd and M. Meadow, Analyt. Chem., 1960, 32, 551.lZ5 F. Feigl, V. Anger, and D. Goldstein, Mikrochim. Acta, 1960, 231.lL6 Y. N. Forostyan and G. V. Lazur'evskii, U.S.S.R.P. 122,634/1959.lX7 V. Anger, Mikrochim. Acta, 1960, 827.12* F. Feigl and D. Haguenauer, Chemist-Analyst, 1960, 49, 43.li9 C. B. Hackett and R. M. Clark, Anatyst, 1960, 85, 683.130 R. E. Dunbar and F.J. Ferrin, Microchem. J., 1960, 4, 167.131 W. E. Hearn and R. Kinghorn, AnaZyst, 1960, 85, 766.132 F. Feigl and D. Goldstein, Analyt. Chem., 1960, 32, 861.133 R. G. Frieser and P. A. Scardaville, AnaZyt. Chew., 1960, 32, 196.134 B. Berisso, Mikvochim. Ada, 1980, 898422 ANALYTICAL CHEMISTRY.and conditions for identification investigated.135 Dibenzofuran-2-sulphonicacid, noted above in connection with amines, serves also to identify amino-acids136 by the crystal forms, melting points, and equivalents of theirderivatives.The precipitation and colour reactions of a number of thio-compoundshave been studied 137 to provide means of detection.Crystal and colour tests are given 13* for 51 modern anaIgesic drugs. Arange of identification data has been tabulated139 for 33 drugs.A newcolour test, unaffected by the usual diluents, has been described for heroin.140Sulphamerazine can be identified in the presence of equal parts of othersulphonamidesIdentification tests, following chromatographic separation of the pesti-cides, are given for captan and methoxychlor,142 and for parathion, parathion-methyl, and Chlorthion.l&5. METHODS OF SEPARATIONMethods of separation are sometimes almost an end in themselves, as inthe preparation of a pure substance to be used as a standard or a reference.More often they are a preliminary to the penultimate process of analysis,that of identification or determination. (The final process, assessment, andpresentation of results, frequently receives scant attention.) In some ana-lytical methods such as gas chromatography, the separation and detection ordetermination are normally, although not invariably, bound up with eachother; but even here a quite different preliminary separation is sometimesneeded.Apart from these, the method of determination need not bedependent on the method of separation, although there are some pairingswhich have obvious advantages, such as precipitation followed by gravi-metry, or solvent extraction followed by flame photometry or spectro-photometry.It is on these considerations that methods of separation are treated intheir own section, and with the suspicion that methods of fusion and fordestruction of organic matter, already dealt with, should rightfully find aplace here.Miscellaneous methods, mainly classical, will be considered first,followed by methods applying to solids, liquids, and gases which have morerecently revolutionised much of the practice of analysis.Miscellaneous.-Amalgam formation, followed by decomposition by acidor electrolysis, has been used1@ to separate gallium from aluminium.Higgins and Baldwin point out that when centrifuging is carried out as13.5 J. Opieliska-Blauth, M. Sanecka, and M. Chareziliski, J. Chromatog., 1960, 3, 415.136 R. E. Dunbar and F. J. Ferrin, Microchem. J., 1960, 4, 59.137 L. Rosenthaler, Pharnz. Acta Helv., 1960, 35, 81.138 E. G. C. Clarke, Bull. Narcotics. 1959, 11, 16.139 M. Brandstatter-Kuhnert, A. Kofler, and 0. Kostenzer, Sci. Pharm.,M.Lerner, Analyt. Chem., 1960, 32, 198.141 A. Coudswaard, Pharm. Weekblad, 1960, 95, 236.112 W. P. McKinleyand S. I. Graham, J . Assoc. O@c. Agric. Chemists,l * ) €3. Sperlich, Apoth.-Ztg., 1960, 100, 774.V. I. Lpsenko and E. V. Lisitsyna, Zavodskaya Lab., 1960, 26, 145.C. E. Higgins and W. H. Baldwin, AnaZyt, Chem., 1960, 32, 236.1960, 28, 7.960, 43, 89CARTWRIGHT AND WILSON: METHODS OF SEPARATION. 423part of an analytical procedure, significant temperature changes can occur,leading to disturbance of solution equilibria. Leslie and Kuehner 146 havereviewed progress in analytical distillation, considering laboratory fractionaldistillation , azeotropic distillation, and information on vapour-liquid equili-brium. A balanced and effective stirrer has been designed for spinning-band distillation c01umns.l~~ The high-vacuum distillation of trace quan-tities of boron as ethyl borate 14* has advantages over normal distillation asmethyl borate.In the determination of microgram amounts of fluorine inplant materials, a method of diffusion in a polythene bottle is emp10yed.l~~Chlorination at high temperatures, long used in metallurgy, has analyticalapplications to many transition elements. Zimmerman and Inglesuse chlorine at 900" to volatilise extraneous elements from the lanthanides.Butler and Hall 151 first bubble the chlorine through sulphur dichloride at40-50" and use a furnace temperature of 500-550" for a similar separation.Zone Melting.-Pfann and Theuerer 152 have reviewed, with 39 references,applications of zone melting and controlled freezing to analytical chemistry.They deal with the concentration of trace impurities to detectable levels,the provision of high-purity standards, direct analysis by zone melting, in-vestigations of phase diagrams, microtechniques, and the determination ofboron and phosphorus in silicon.The efficiency of zone refining of alumin-ium has been investigated,153 by using neutron activation determination of13 impurity elements. A simple apparatus which permits the passage,during a run, of 18 molten zones with cooling between each, through asample of organic compound, is described by Joncich and Bailey.l=Solvent Extraction.-The straightforward elution of inorganic and organicconstituents on the basis of their solubilities, although by no means alwaysempirical, requires little comment.There is, however, a still increasingvolume of work, developing largely on sound physical principles, on theextraction into organic solvents of metal complexes as a method of separ-ation. This forms the bulk of the following report.Morrison and F r e i ~ e r l ~ ~ have reviewed progress in the subject up tolate 1959. Tr6millon gives a general account 156 with special reference tothe behaviour of the organic phase and displacements of equilibria in theaqueous phase. Oosting 15' extends his theoretical development of thesubject by deriving formulz covering the cases where the complex is solublein both phases, and where it is soluble in the aqueous, but not the organicphase, and gives supporting experimental evidence.A simple apparatus ,based on a thin-walled Polythene bottle, has been devised15* for carryingR. T. Leslie and E. C. Kuehner, Analyt. Chem., 1960, 32, 2 6 ~ .147 W. F. Pease, A. H. Gilbert, and A. Cahn, Analyt. Chem., 1960, 32, 894.148 C. A. Parker and W. J. Barnes, Analyst, 1960, 85, 828.14s R. J. Hall, Analyst, 1960, 85, 560.J. B. Zimmerman and J. C. Ingles, Analyt. Chem., 1960, 32, 241.151 J. R. Butler and R. A. Hall, Analyst, 1960, 85, 149.lS2 W. G. Pfann and H. C. Theuerer, Analyt. Chem., 1960, 32, 1574.lS3 W. D. Macintosh, Analyt. Chem., 1960, 32, 1272.lS4 M. J. Joncich and D. R. Bailey, Analyt. Chem., 1960, 32, 1578.15j G. H. Morrison and H. Freiser, Analyt. Chem., 1960, 32, 3 7 ~ .136 B.Tr&millon, Bull. SOC. claim. France, 1960, 1011.l+jR T. W. Steele, Afialyst, 1960, 85, 153.M. Oosting, Bec. Trav. chim., 1960, 79, 627424 ANALYTICAL CHEMISTRY.out extractions. Dean 159 mentions the advantages of solvent extraction asa preliminary to flame-photometric determinations in metallurgical analysis.Applications to the separation of particular metals are very numerous;the following selection is arranged in the .order of the Periodic Classification,complicated by the many cases where a number of cations have been studiedtogether.Main grozCp elements. Lithium chloride is separated from sodiumchloride 160 by extraction with anhydrous dioxan containing metallic sodiumand calcium to destroy water. The partition of the oxinates of beryllium,magnesium, and the alkaline-earth metals between water and chloroform inthe presence and absence of n-butylamine has been studied.161Boron in steels is separated16* by extraction of the Methylene Blue-tetrafluoroborate complex into 1,2-dichloroethane.Gallium has beenextracted as its Rhodamine B complex from hydrochloric acid solution con-taining acetone, by means of benzene; 163 it can be separated from indiumby extraction from hydrochloric acid solution with ether,l@ or with ethylacetate of its complex with diethyldithiocarbamate in the presence of excessof oxalate.l= Gallium and indium, together with many transition elements,can be selectively extracted with 1-(2-pyridylaz0)-2-naphthol (PAN) .166Silicon can be extracted as molybdosilicic acid with tri-isodecylamine intoluene.lG7 Phosphorus can be separated from silicon by selective extractionof molybdophosphoric acid with ethyl acetateJ168 or by first forming theheteropoly-blue compound of both by reduction with l-amino-Z-naphthol-4-sulphonic acid, followed by extraction of the phosphorus compound withdiethyl ether.169 Very small quantities of lead may be determined in rocksand meteorites by distilling it at 1400" and extracting it with dithi20ne.l~~Dithizone extraction has also been applied to simultaneous extraction ofbismuth and lead from a solution in which other metals are masked, followedby return to acid solution and separate extraction of bismuth and thenlead.171 Bismuth, tin, and lead in natural waters, together with seventransition metals, are extracted into chloroform containing diethyldithio-carbamate 172 for spectrographic determination.Extraction methods forlead and traces of copper form part of a composite procedure for the analysisof aluminium bronze all0ys.1~~ Selective extractants for a number ofJ. A. Dean, Analyst, 1960, 85, 621.160 E. Blasius and F. Wolf, 2. analyt. Chem., 1960, 174, 349.161 F. Umland, W. Hoffmann, and K.-U. Meckenstock, 2. anaZyt. Chem., 1960, 173,162 L. Pasztor, J. D. Bode, and Q. Fernando, Analyt. Chem., 1960, 32, 277.163 V. K. Kuznetsov and N. A. Tananaev, Ref. Zhur., Khim., 1960, Abstract No.164 E. P. Cocozza, Chemist-Analyst, 1960, 49, 46.165 A. I. Busev, T. N. Zholondkovskaya, and 2. M. Kuznetsova, Zhur.analit.166 Shozo Shibata, Analyt. Chim. Acta, 1960, 23, 367.167 H. N. Wilson and J. M. Skinner, Rec. Trav. chim., 1960, 79, 574.168 J, Paul and W. F. R. Pover, Analyt. Chim. Acla, 1960, 22, 185.169 J. Paul, Analyt. Chim, Acta, 1960, 23, 178.R. R. Marshall and D. C . Hess, Analyt. Chem., 1960, 32, 960.li1 R. Socolovschi, Rev. Chim. (Roumania), 1960, 11, 348.1 7 2 I. T, Klimov and V. Y . Eremenko, Ref. Zhur., Khim., 1960, Abstract No. 56,770.173 M. Freegarde and B. Allen, Analyst, 1960, a, 731.211.56,694.Khim., 1960, 15, 49CARTWRIGHT AND WILSON : METHODS OF SEPARATION. 426selenium compounds have been described.174 Polonium can be extractedfrom hydrochloric acid solutions of bismuth by 2,4-dimethylpentan-3-01 or2,6-dimethylheptan-4-01 (di-isopropyl- or di-isobutyl-carbinol) .175By virtue of their complex-forming power, transi-tion elements are very amenable to solvent-extraction processes.Withproper pH control, PAN is a very selective extraction agent for cadmium,zinc, mercury, manganese, and iron, as well as gallium and indium.Copper in beryllium and beryllium oxide can be extracted as its neo-cuproin complex at pH 5 into isobutyl methyl ketone, other elements beingmasked by citric acid.176 The diethylammonium diethyldithiocarbamatecomplex in carbon tetrachloride serves to separate copper from lead alloys,and the dithizone complexes of copper and zinc, in biological materials,can be selectively extracted into chloroform.178 Schweitzer et al. have madea quantitative study, over a range of pH, and using various aqueous andorganic phases, of the extraction of silver ~ x i n a t e , l ~ ~ and silver and cadmiumdithizonates.l8O Silver has been extracted as its compound with tri-n-butyl-ammonium saccharin with dichloromethane at pH 4-5.Tri-iso-octylthiophosphate and tri-n-butyl thiophosphate are highly selective extractantsfor silver and mercury(I1); a thorough investigation into the use of thesereagents has been made.182 The gold complex with p-dimethylamino-benzylidenerhodanine is extractable into isopen tyl acetate .lS3A method for the extraction of mercury into carbon tetrachloride fromcarbonate buffered solutions, containing EDTA and cyanide as maskingagents, uses the diethyldithiocarbamate complex lS4 and should be applic-able to a wide variety of samples.Cerium(1v) la5 and chromium(II1) lS6 are extracted from faintly acidsolution into benzene as the 2-thenoyltrifluoroacetone complexes.Thepresence of acetic acid enhances the extraction of thorium, using the samereagent, into carbon tetrachloride or isobutyl methyl ketone; the reasonshave been studied.ls7The separation of vanadium(1v) from a number of other metals, byextraction from acid solution into ethyl acetate with cupferron, has beendescribed.ls8 Niobium can be separated from tantalum by extraction intoisobutyl methyl ketone from hydrochloric, sulphuric, and tartaric acids.lSQTransitiort elements.174 N. A. Filippova, L. A . Martynova, E. V. Savina, and R. D. Kulichikhina, Zaetod-175 F.L. Moore, Analyt. Chem., 1960, 32, 1048.I i 6 J. 0. Hibbits, W. F. Davis, and M. R. Menke, Talanta, 1960, 4, 101.177 J. H. Thompson and M. J. Ravenscroft, Analyst, 1960, 85, 735.17* K. 0. Raker, 2. analyt. Chem., 1960, 173, 57.17s G. K. Schweitzer and E. T. Bramlitt, Analyt. Chim. Acta, 1960, 23, 419.lS0 G. K. Schweitzer and F. F. Dyer, Analyt. Chim. Acta, 1960, 22, 172; F. F. Dyer181 M. Ziegler, H. Sbrzesny, and 0. Glemser, 2. analyt. Chem., 1960, 173, 411.188 T. H. Handley and J. A. Dean, Analyt. Chem., 1960, 32, 1878.183 T. M. Cotton and A. A. Woolf, Analyt. Chim. Acta, 1960, 22, 192.18* E. A. Hakkila and G. R. Waterbury, Analyt. Chem., 1960, 32, 1340.S. M. Khopkar and A. K. De, Analyt. Chem., 1960, 32, 478.lS6 S. K. Majumdar and A.K. De, Analyt. Chem., 1960, 32, 1337.ly7 G. Goldstein, 0. Menis, and D. L. Manning, Analyt. Chem., 1960, 32, 400.lR8 C. M. Stander, Analyb. Chem., 1960, 32, 1296.lR9 P. Senisc and L. Sant’Rgostino, Awlyt. Chim. A d a , 1960, 22, 296.skuya Lab., 1960, 26, 401.and G. K. Schweitzer, ibid., 1960, 23, 1426 ANALYTICAL CHEMISTRY.In the presence of tungsten, molybdenum may be extracted into chloro-form with 5-phenyl-2-pyrazoline-1-dithiocarbamic acid.lgO A study hasbeen made of chloroform solutions of a-benzoin oxime for the extraction(and precipitation) of chromium, molybdenum, tungsten, and vanadium ; lglneither the chromium nor the tungsten complex is of value in extraction,but molybdenum may be extracted, with masking of tungsten and vanadium,and vanadium may also be extracted.Tungsten can be extracted withpentyl alcohol as the thiocyanate complex, although molybdenum interferes;the process has been investigated using radi0-t~ngsten.l~~A number of methods have been investigated for the separation ofuranium and some transuranic elements. Uranium and protactinium canbe separated from thorium by extraction with a secondary amine.lg3 Thetributyl phosphate extraction of uranium 194 and uranium and plutonium lg5has been studied and applied. Uranium has also been separated byextraction with 2-thenoyltrifluoroa~etone,~~~ 1-(2-pyridylaz0)-2-naphthol,~~~and tri-iso-o~tylamine.~~~ From uranium-fission product mixtures, neptun-iumlg9 and plutonium200 in oxidised form may be extracted as nitratecomplexes into isobutyl methyl ketone, and in reduced form into thenoyl-trifluoroacet one-xylene.Solvent-extraction procedures are used in a scheme 201 for the separationand identification of manganese, technetium, rhenium, ruthenium, andmolybdenum on the ultramicro-scale.Manganese is removed by solventextraction from calcium and magnesium in a titrimetric method202 fordetermining all three.Iron(II1) may be extracted from iron(11) by acetylacetone in carbon tetra-chloride, permitting determination of both in s0lution.~03 Thenoyltrifluoro-acetone,= trioctylphosphine 4-methylpentan-2-0ne,~~~ and thio-cyanate 207 have all been used under various conditions in the extraction ofiron. Cobalt may be separated from iron and other metals by l-nitroso-%naphthol in the presence of or by tributyl phosphate a t highlSO A.I. Busev, V. M. Byr’ko, and I. I. Grandberg, Vestn. Moskov. Univ., Ser. Khim.,1960, 76.l91 H. J. Hoenes and K. G. Stone, Talanta, 1960, 4, 260.192 V. Pfeifer, Mikrochim. Acta, 1960, 518.l93 Fujis Ichikawa and Shinobu Uruno, Bull. Chem. SOC. Japan, 1960, 33, 569.194 H. Menke and G. Herrmann, Z. analyt. Chem., 1960, 175, 324; T. S. Urbariski,Chem. Analit., 1960, 5, 283; V. Pfeifer and F. Hecht, Mikrochim. Acta, 1960,378.195 R. P. Larsen and C. A. Seils, jun., Analyt. Chem., 1960, 32, 1863.lS6 S. M. Khopkar and A. K. De, Analyst, 1960, 85, 376.Ig7 Shozo Shibata, Analyt. Chim. A d a , 1960, 22, 479,lS8 F. L. Moore, Analyt. Chem., 1960, 32, 1075.199 W. J.Maeck, G. L. Booman, M. C. Elliott, and J. E. Rein, Analyt. Chem., 1960,200 W. J. Maeck, G. L. Booman, M. E. KUSSY, and J. E. Rein, Analyt. Chem., 1960,201 F. Jasim, R. J. Magee, and C. L. Wilson, Talanta, 1960, 4, 17.Z o 3 0. Gjems, Analyst, 1960, 85, 738.203 K. H. Lieser and H. Schroeder, 2. analyt. Chem., 1960, 174, 174.2*4 S. M. Khopkar and A. K. De, Analyt. Chim. Acta, 1960, 22, 223.zo5 J. 0. Hibbits, W. F. Davis, and M. R. Menke, Talanta, 1960, 4, 61.2ikR E. Cogan, Analyt. Chein., 1960, 32, 973.32, 605.32, 1874.0. Menis and T. C. Rains, AnaZyt. Chem., 1960, 32, 1837.J. Fischl, Clinica Chim. Acta, 1960, 5, 164CAKTWRIGHT AND WILSON : METHODS OF SEPARATION. 427hydrochloric acid ~oncentration.20~ In beryllium and beryllium oxide, itmay be separated by extracting the beryllium and other metals with acetyl-acetone, and then the cobalt as thiocyanate.210Palladium is separated from niobium and zirconium by extraction ofiodopalladate into isobutyl methyl ketone.211 Palladium, rhodium, andruthenium can be separated by selective extraction as their oxine complexesinto chloroform ,212In addition to the great variety of extractive processes for metals, thereis the indirect application of the method to the determination of certainanions which can affect, quantitatively, the efficiency of extraction of ametal.Fluoride, for example, prevents the extraction of hafnium intotrioctylphosphine. Radio-hafnium being used as a tracer, the efficiency ofextraction of hafnium is measured, and this is inversely related to fluoride~ n t e n t .~ 1 3Chromatography.-The term chromatography ceased to have any literalmeaning early in its history. It is now applied, for want of a better term,to a wide variety of phenomena of fractional partition, adsorption, extraction,ionic exchange, electrical migration, extraction, and precipitation methodswhich overlap most physical separation methods, and have in common onlythe provision of a solid, or solid-supported liquid, surface on which theseparations are carried out. There is seldom nowadays the requirement ofcolour or of direct visual indication of position. Strain,214 in a survey of itsfundamental developments, deals comprehensively with the classification ofits ramifications. For ease of reference in this Report, however, chromato-graphy is limited to liquid-phase methods on columns, paper, or gels.Electrophoresis, ion exchange, and gas chromatography are given separateheadings.Over the complete field the Report is mainly one of continued applicationrather than of rapid fundamental advance.CoZfimn chromatography.A number of mechanical and electrical aids tocolumn separations have been described. Harpur 215 describes switches forcontrolling turntables and siphons, and a siphon counter. Automaticfraction collectors have been devised of simple 216 for simultaneouscollection from a number of and for collection for subsequentevaporation.218 An automatic valve for constant-volume collection isdescribed,219 and a " Teflon " (PTFE) glass pump for supplying solventunder pressure and for other uses.22o An apparatus for multiple-columnV.T. Athavale, S. V. Gulavane, and M. M. Tillu, Analyt. Chim. Acta, 1960, 23,487.210 J. 0. Hibbits, A. F. Rosenberg, and R. T. Williams, Talanta, 1960, 5, 250.211 J . F. Duke and W. Stawpert, Amalyst, 1960, 85, 671.213 F. Jasim, R. J. Magee, and C. L. Wilson, Rec. Trav. chim., 1960, 79, 541.21a W. J. Maeck, G. L. Booman, M. C. Elliott, and J. E. Rein, Analyt. Chem., 1960,214 H. H. Strain, Analyt. Chem., 1960, 32, 3 ~ .21s R. P. Harpur, Chemist-Analyst, 1960, 49, 24, 50.216 H. Zahnd and M. Citron, Chemist-Analyst, 1960, 49, 29.217 P. Vestergaard, J . Chromatog., 1960, 3, 554.218 J. H. Schwartz, J . Chromatog., 1960, 3, 491.G. J.Nelson, Analyt. Chem., 1960, 32, 1724.220 A. C. Arcus, J . Chromatog., 1960, 3, 411.32, 922428 ANALYTICAL CHEMISTRY.gradient elution 221 ensures that the gradual change of solvent is the same foreach column.O’Sullivan discusses the mechanism of solvent mixing in gradientelution,222 and the regulation of the composition of the eluent. A measureof the surface area of silica and alumina-silica column packings is given,223within limitations, by the length of adsorbed zone of Methyl Red frombenzene.For inorganic work, cellulose is the most favoured column packing. Ithas been used to separate zinc from indium and nickel2% by elution withn-butyl alcohol-hydrochloric acid, with added iron to indicate band position.Uranium can be freed from iron and vanadium by elution on cellulosecolumns by using isobutyl methyl ket0ne.~~5 A composite method forseparating the platinum metals 226 uses a two-stage process on a cellulosecolumn, with first a reducing solvent to elute platinum and palladium, andthen an oxidising one to elute rhodium and iridium. Other column packingsfor inorganic work often involve modifying the packing material.A“ siliconised ” silica gel column treated with tributyl phosphate 227 is usedto separate niobium and tantalum, and is reminiscent of solvent extraction.Siliconised Celite will adsorb molybdophosphoric acid formed from ortho-phosphate, while other phosphate compounds pass through.228 Activatedcarbon, saturated with phenylarsonic acid 229 and dried, is used for separatingniobium and tantalum.Precipitation chromatography, in which a gel isimpregnated with a precipitating agent, diffusion of the test solution givingsharp bands of precipitate, has been used to separate with more or less cer-tainty mixtures of metals giving insoluble sulphides,sO and, by measurementof zone widths, to determine zinc.231In organic separations, activated alumina has had wide application,mainly to a range of natural products, as in the separation of the activeconstituents of pyrethr~m,2~~ of digitoxin in digitalis leaves,233 and ofalkaloid salts,234 and to a host of biological materials. It has also been usedin incidental separation or purification stages in the determination of tracesof organic materials, sometimes involving a number of successive separationswith different s0lvents.~35 Cellulose and modified celluloses are used toseparate ascorbic acid 236 and proteinsB7 Celite may be modified by buffer221 P.Vestergaard, J . Chromatog., 1960, 3, 560.222 D. G. O’Sullivan, Analyst, 1960, 85, 434.233 H. A. Benesi, Analyt. Chem., 1960, 32, 1410.224 E. G. Towndrow, R. Hutchinson, and H. W. Webb, Analyst, 1960, 85, 769.225 T. PalBgyi, Acta Chim. Acad. Sci. Hung., 1960, 22, 239.226 S. T. Payne, Alzalyst, 1960, 85, 698.227 S. Sekerskii and B. Kotlinskaya, Ref. Zhur., Khim., 1960, Abstract No. 13,064.2z8 B. Hagihara and H. A. Lardy, J . Biol. Chem., 1960, 235, 889.229 L. S. Aleksandrova and K. V. Chmutov, Izvest. Akad. NauR S.S.S.R., 1960, 801.23O J. D. Spain, Analyt.Chem., 1960, 32, 1622.23l I. N. Grigorenko, N. L. Olenovich, and A. A. Morozov, Zhur. analit. Khim., 1960,232 H. J. Smith. J . Sci. Food Agric., 1960, 11, 172.233 F. Neuwald, H.-J. Didier, and G. Grimmer, Pharm. Acta Helv., 1960, 35, 87.234 H. Bohme and H. Hocke, Arch. Pharm., 1960, 293, 342.235 J. R. Pasqualini, Compt. rend., 1960, 250, 3892.236 I. Crossland, Acta Chem. Scand., 1960, 14, 805.23’ S. Mandeles, J . Chromatog., 1960, 8, 266.15, 115CARTWRIGHT AND WILSON : METHODS OF SEPARATION. 429in the separation of phenoxyacetic acid~,2~* or organic liquids to provide astationary liquid phase, as in the use of methyl cyanide or 2-chloroethanol inthe separation of dinitrophenylhydra~ones.~~ Many other packingmaterials, including activated carbon,%O molecular sieves,241 kieselguhr withalbumin,242 polyamide 244 and starch 245 have their particularuses, but the only one to rival alumina in versatility is silica gel.It has beenemployed in the separation of polycyclic hydrocarbons,246 organic acids inriver waters ,247 series of dibasic free and esterified cholesterol incerebrospinal fluid,249 and, mixed with other supports, for phenothiazine 250and dinitrophenylhydrazine deri~atives.~51Apparatus has been devised for lowering papersto the solvent after equilibration has taken place,252 and for preparing,applying, and developing oxidisable samples in an inert atmosphere.253Slow application of large volumes of solutions through a syringe while airpressure under the point of application is reduced ensures rapid concen-tration of the The elution of large pieces of paper with smallvolumes of solvent,255 and the controlled elution of a large number of strips,256have been described.Much greater rapidity in development, with sharperresolution , is claimed for a device 257 whereby paper strips, arranged radially,are centrifuged during elution. A rapid estimate of zone content may bemade by rectified low-frequency measurements of conductance of the elutedRadioassay of zones containing labelled atoms has been im-260 A bibliography on radial development chromatography,mainly from 1957 onwards, has been published.261A theoretical and experimental study has been made of zone migration inpaper chromatography,262 and the reasons for limitations in the applicabilityPaper chromatography.238 F.Martin and M. Pallibre, Bull. Soc. chim. France, 1960, 375.239 E. A. Corbin, D. P. Schwartz, and M. Keeney, J . Chromatog., 1960, 3, 322.240 R. L. Stambaugh and D. W. Wilson, J . Chromatog., 1960, 3, 221.241 J. G. O'Connor and M. S. Norris, Analyt. Chem., 1960, 32, 701.242 J. D. Mandell and A. D. Hershey, Analyt. Biochem., 1960, 1, 66.243 2. KotAsek, J. Strachota, M, VAvrovQ, and J. SpiCkovQ, Chem. prumsyl, 1960,244 J. Davfdek, 2. L.ebensm.-Um?erswch., 1960, 112, 272.245 A. DrPze, Bull. SOC. Chim. biol., 1960, 42, 407.246 D. Hoffmann and E. L. Wynder, Analyt. Chem., 1960, 32, 295.247 H. F. Mueller, T. E. Larson, and M. Ferretti, Analyt. Chem., 1960, 32, 687.248 E. D. Smith, Analyt.Chem., 1960, 32, 1301.249 N. M. Papadopoulos, W. Cevallos, and W. C. Hess, J . Neurochem., 1959,250 D. Gunew, Analyst, 1960, 85, 360.251 M. L. Wolfrom and G. P. Arsenault, Analyt. Chem., 1960, 32, 693.25a R. S. Potter, E. M. Linday, and R. Chayen, J . Chromafog., 1960, 3, 202.253 P. Szarvas, T. Balogh, and L. MQczay, Magyar Kbm. Folydirat, 1960, 66,254 J. Logothetis, J . Chromatog., 1960, 3, 488.255 M. J. Canny, J . Chromatog., 1960, 3, 496.256 J. Skolik, J . Chromafog., 1960, 3, 273.257 J. R. Tata and A. W. Hemmings, J . Chromatog., 1960, 3, 225.258 G. G. Blake, Analyt. Chim. Acta, 1960, 22, 546.259 W. F. Bousquet and J. E. Christian, Analyt. Chem., 1960, 32, 722.260 H. Ludwig, V. R. Potter, C. Heidelberger, and C. H. de Verdier, Biochim.Bio-261 L. Peyron, Bull. SOC. chim. France, 1960, 1243.262 J. C. Giddings, G. H. Stewart, and A. L. Ruoff, J . Chromafog., 1960, 3, 239.10, 321.4, 223.137.phys. Acta, 1960, 3'7, 525430 ANALYTICAL CHEMISTRY.of theoretical principles are discussed. The origins and formation of multiplezones by pure substances have been d i s c ~ s s e d . ~ ~ ~ ~ ~ ~Inorganic paper chromatography has an extensive literature, particularlyconcerned with the separation of small closely-related groups of ions. A fewof the interesting separations which have been devised are described below.Some of the alkali metals can be separated by elution with methanol con-taining aqueous ammonia,2@' and many separations among the alkali andalkaline-earth metals, using 2-ethoxyethanol or acetone with dilute hydro-chloric acid, can be obtained.266 Of a number of metals forming insolublesulphides, only lead will pass through a cadmium sulphide zone on a paperstrip under conditions described.267 The modifying effect of anions presenton the behaviour of bismuth on paper strips eluted with butanol-thiocyanatesolvent has been studied.268 Separations of lanthanides, mainly amongnon-adjacent pairs, can be obtained with butanol on strips saturated withacid lithium nitrate.269 Six solvent mixtures for separation of yttrium andzirconium have been li~ted.~~O Selenium, tellurium, and polonium, andlead, bismuth, and polonium, can be separated with a butanol-propanoleluant containing acid lithium nitrate.271 Acid butyl acetate or ethylmethyl ketone can be used for semi-quantitative determination of uranium.272The prior formation of complexes and their separation by chromatographyin organic solution is applicable in many separations. Oxinates 273*274 andtartrates 275 of a number of metals may be used. A study has been madeof the separation of ten anions by ascending paper chromatography, butanol-acetone-water being used as solvent,276 and 24 anions are included in ascheme employing ethanol-pyridine-aqueous ammonia.277 Chloride can beseparated as its silver-ammonia complex and determined by exposing thespot to ultraviolet light.278 A most delicate method for determining metaltraces in high-purity water involves adsorption, from a large volume ofliquid, of the metals on a disc of cellulose phosphate.279Space limits consideration of organic paper chromatography to a verysmall fraction of the available work of the last year.Most of this work hasbeen concerned with separation or purification prior to determination ofparticular compounds or small groups of compounds. These have had to beomitted, and the report is concentrated mainly on a selection of separations,or detailed chromatographic studies, of classes of compounds.263 R. A. Keller and J. C. Giddings, J . Chromatog., 1960, 3, 205.264 A. H. Beckett, M. A. Beaven, and A. E. Robinson, Nature, 1960, 186, 776.268 E. C. Martin, Analyt. Chim. Acta, 1960, 22, 142.266 A. K. Majumdar and B. K. Pal, Z. analyt. Chem., 1960, 174, 429.267 M. Ziegler, Z.analyt. Chem., 1960, 174, 323.E. C. Martin, Analyt. Chim. Acta, 1960, 22, 228.J. Danon and M. C. Levi, J . Chromatog., 1960, 3, 193.270 G. Kallistratos, A. Pfau, and B. Ossowski, Analyt. Chim. Acta, 1960, 22, 195.271 M. C. Levi and J. Danon, J . Chromatog., 1960, 3, 584.2i2 T. PalPgyi, Acta Chim. Acad. Sci. Hung., 1960, 22, 131.273 A. Lacourt and P. Heyndryckx, Mikrochim. Acta, 1960, 473.271 I. Krausz, Magyar K h . Folybirat, 1960, 66, 296.275 E. J. Singh and A. K. Dey, J . Chromatog., 1960, 8, 146.276 H. Laub, Z. analyt. Chem., 1960, 173, 208.277 I. I. M. Elbeih and M. A. Abou-Elnaga, Analyt. Chim. Acta, 1960, 23, 30.278 F. Baykut and S. (Izeris, Istanbul Univ. Fac. Mecnzuasi, 1959, @, 79,37s F, F, Kember, Analyst, 1960, 85, 449CARTWRIGHT AND WILSON: METHODS OF SEPARATION.431Polycyclic aromatic hydrocarbons in trace amounts in cigarette smoke 280have been separated by elution with methanol-ether-water and othersolvents. Lower aliphatic alcohols can be separated as their xanthates byusing water-saturated butanol or pentanol,281 or as their 3,5-dinitro-benzoates.B2 The latter method has been employed with polyhydricalcohols, combined with a chromatographic study of the free alcohols.283Aliphatic ethers can also be converted into esters of 3,5-dinitrobenzoic acidfor paper chromatographic separation.= Data for eight ketones and threealdehydes, separated as their 2,4-dinitrophenylhydrazones, are given.285A detailed study, involving 111 organic acids of several homologousseries,286 has been made of correlations between chromatographic behaviourand structure. A number of aromatic acids may be separated 287 by usingpropanol-aqueous ammonia. Chromatography of substituted phenoxy-acetic acids has received intensive study,288 and the nature of their attach-ment to the cellulose and its modification by substituents clarified.Straight-chain aliphatic, and other, acids may be separated on paper saturated withdimethyl sulphoxide by using a number of solvents.289 Saturated, unsatur-ated, and hydroxy-aliphatic acids are treated on paper impregnated withliquid paraffin.290 The behaviour of 21 common phenolic acids found inplant materials has been studied by two-dimensional development .291 Asimilar number of substituted and unsubstituted phenols have been separatedas their 4-nitrophenylazo-derivati~es,~~~ and their behaviour has been relatedto the position of substituents.Polyamide-impregnated paper has beenused for chromatography of phenols.293 Thirty-seven aminoanthraquinoneshave been studied on paper impregnated with l-bromonaphthalene orf~rrnamide.~~*The separation of aliphatic primary amines as N-alkyl-3,5-dinitrobenz-amides on paper saturated with formamide has been described; 295 amineshave also been separated on paper containing an ion-exchange resin.296Data for multiple paper chromatography of 29 amino-acids are presented.297Water-soluble dyes have been studied. Chromatographic data are givenfor 70 dyes in one publication,298 and 49 in another.299 Cellulose esters and2so J.PavlC and J. h l a , Cas. Lkk. ces., 1960, 99, 101.2s1 R. Pholoudek-Fabini and T. Beyrich, Pharm. ZentralhaZle, 1960, 99, 341.282 G. E. Zaikov, Zhur. anaZit. Khim., 1960, 15, 104.283 J. Borecky and J. GaspariE, Coll. Czech. Chem. Comm., 1960, 25, 1287.284 M. JureEek, M. Hubik, and M. VeCeFa, Coll. Czech. Chem. Comm., 1960, 25, 1458.385 E. Breuer, €3. Leader, and S. Sarel, Bull. Res. Council, Israel, 1960, 9, A , 43.2y6 J. R. Howe, J . Chromatog., 1960, 3, 389.287 L. V. Golosova and G. B. Ovakimyan, U.S.S.R.P. 121,964/1959.288 L. S. Bark and R. J. T. Graham, Analyst, 1960, 85, 663, 905, 907.289 G. Hammarberg and B. Wickberg, Acta Cltem. Scand., 1960, 14, 882.2g0 V. P. Skipski, S. M. Arfin, and M. M. Rapport, Arch. Biochem.Biophys., 1960,291 R. K. Ibrahim and G. H. N. Towers, Arch. Biochem. Biofihys., 1960, 87, 125.292 E. Fedeli, A. Fiecchi, and G. Jommi, Gazzetta, 1959, 89, 824.r193 K.-T. Wang, Riechstofle u. Aromen, 1960, 10, 158.n91 J. GaspariC, J . Chromatog., 1960, 4, 75.205 M. VeEefa, B. VolAkovA,, M. KozzikovA, and M. JureEek, Coll. Czech. Chem.286 A. Lewandowski and A. Jarczewski, Talanta, 1960, 4, 174.297 M. S. Dunn and E. A. Murphy, Analyt. Chem., 1960, 32, 461.29s K. Woidich, T. Langer, and L. Schmid, Deut. Lebensm.-Rundschau, 1960, 56, 73.299 J. C. Riemersma and F. J. M. Heslinga, Mitt. Lebensmitt. Hyg., Bern, 1960, 51, 94.87, 259.Comm., 1960, 25, 1281432 ANALYTICAL CHEMISTRY.ethers can be separated on paper.3oo The chromatographic behaviour ofalkaloids derived from piperidine,301 and of derivatives of barbituric acid,302has been studied.Studies303~304 of the separation of steroids of the corti-coid type have been made. Satisfactory separation has been achieved of anumber of di- and tri-alkyl-tin comp0unds.m“Flat ” chromatography can be varied by substituting films of othermaterials for the usual paper. Glass plates coated with a thin layer of silicagel have been used in the separation of weakly polar steroids 306 and vitaminsof the B complex.307 A study of the potentialities of thin-layer silica geland cellulose cliromatography has been made.308 The provision, on paperstrips, of a band of reagent through which the sample is eluted has alreadybeen mentioned; 267 it has been applied in organic work, particularly tothe separation of related compounds, by applying a band of reagentwhich will form derivatives with the sample.A number of examples aregiven.309Electrophoresis.-Since such lists could not be comprehensive, therewould be little advantage in detailing particular application of electro-phoresis to inorganic, and even less so to organic, materials. The examplesof apparatus and methods selected are those of represerltative interest orpotentially wider application.An apparatus, suitable for simultaneous development af several iono-pherograms, has been designed310 to overcome staining by copper wireelectrodes. The use of palladium electrodes is advocated 311 to permit highcurrent densities without gassing.The cathode absorbs hydrogen, and theanode is cathodically charged with hydrogen before use; a modification isdescribed which allows indefinite use without formation of gas. A com-bination of agar gel and paper which gives concentration of zones is de-scribed.312 Microelectrophoresis on cellulose acetate membranes isclaimed 313 to give improved speed and clarity. By moving the paper in theopposite direction to that of the ion migration, keeping the sample midwaybetween the electrodes until separation is complete, and by immersing thepaper in cooled carbon tetrachloride to allow higher voltages and currents,efficient separation of amino-acids can be achieved.314 In vertical-columnelectrophoresis of proteins, improved control is possible if the columns are300 E.B. Mano and L. C. 0. Cunha Lima, Analyt. Chem., 1960, 32, 1772.3O1 J. Massicot, Bull. SOC. chim. France, 1959, 1825.302 A. Macek, Arch. Pharm., 1960, 298, 546.3O3 J. C. Touchstone and M. Kasparow. Analyt. Biochem., 1960, 1, 91.304 G. Cavina and E. Cingolani, Farmaco, E d . Prat., 1960, 15, 246; T.C. 1 s t . Sup.305 D. J. Williams and J. W. Price, Analyst, 1960, 86, 579.308 M. J. D. van Dam, G. J. de Kleuver, and J. G. de Heus, J . Chromatog., 1960,307 H. Ganshirt and A. Malzacher, Naturwiss., 1960, 47, 279.308 K. Teichert, E. Mutschler, and H. Rochelmeyer, Apoth.-Ztg., 1960, 100, 283.30s A. Becker, 2. analyt. Chem., 1960, 174, 161.310 S. Lovett, Chem. and Ind., 1960, 709.818 B. Zak, F. Volini, J. Briski. and L. A. Williams, Amer.J. Clin. Path., 1960, 33, 75.315 B. W. Grunbaum, P. L. Kirk, and W. A. Atchley, Analyt. Chem., 1960, 32, 1361.314 S. Natelson, J. B. Pincus, F. J. Annecchiarico, and E. Schmerzler, Microchem J . ,Sanit., 1960, 23, 254.4, 26.R. Neihof and S. Schuldiner, Nature, 1960, 185, 526.1960, 4, 145CARTWRIGHT AND WILSON : METHODS OF SEPARATION. 433closed with membranes of regenerated cell~lose.~~5 Direct photometry witha small range of colour intensities is possible for lipid electropherog~ams,~~~and ultraviolet direct photometry at 200 and 260 rnp has been used fornucleicThe alkali-metal cations can be separated on paper by using a potentialgradient of 15 v per cm., with ammonium formate and trichloroacetic acidin nitromethane as solvent,31s Traces of a number of heavy metals insodium citrate buffer have been separated by using a 300 v potential.320A series of buffers from pH 3.3 to 9.3 in formamide is used to obtainrapid electropherograms of a variety of classes of organic compounds.321Reference dyes are used to indicate mobilities, and relative figures fordifferent pH values can often permit classification of an unknown.A studyhas been made a22 of the relation between the structure of anthraquinonederivatives and their electrophoretic mobility. The value of addition ofsmall percentages of carboxymethylcellulose to the buffer employed in paperelectrophoresis is disc~ssed.~~3 Copper complexes of some amino-acids areused in paper electroph~resis.~~ In the electrophoresis of nucleic acids onfreshly prepared silica gel, it is concluded that the gel acts as a molecularsieve, allowing ribonucleic acid and peptides to migrate, but restrainingdeoxyribonucleic acid and proteins.325An apparatus enabling eight micro-samples to be run simultaneously,with high reproducibility, is described.326 In a method termed focusing ion-exchange,327 samples of fission isotopes are placed on a paper bridge immersedin carbon tetrachloride.One end of the paper dips into an anode solutionof hydrochloric acid, the other into a cathode solution of citric acid OF EDTA.Separation takes 5 minutes with a potential of 260-280 v and a current of2-10 rnA.Ion-exchange.-As with electrophoresis, the report deals with fewparticular applications (more abundant here in the inorganic field) but ratherwith papers of wider interest.Granular or liquid ion-exchange resins may be used 32* to concentratetrace materials for direct analysis by X-ray fluorescence.The conditionsfor successful application are discussed. Two indirect uses of ion-exchangeresins have been described. By adsorbing reducing or oxidising ions on toa column, it is effectively converted into an electron-exchanger; 329 for315 S. Sorof, E. M. Young, M. M. Spence, and P. L. Fetterman, Biochim. Biophys.Ada, 1900, 38, 559.816 R. Y. Vysotskii and V. F. Baumgart, Ref. Zhur., Khim., Biol. Khim., 1960,Abstract No. 8867.317 N. Ressler, Naturwiss., 1960, 47, 228.318 H. Bloemendal, J . Chromatog., 1960, 3, 509.319 M. M. Tuckerman and H.H. Strain, Analyi. Chem., 1960, 32, 695.320 D. Malysz, Acta Polon. Pharm., 1060, 17, 221.321 L. M. Werum, H. T. Gordon, and W. Thornburg, J . Chromatog., 1960, 8, 125.322 J. Franc and M. Wurst, Coil. Czech. Chem. Comm., 1960, 25, 657.323 R. Holmes and S. W. Wolfe, Arch. Biochem. Biophys., 1960, 87, 13.324 M. Szwaj and M. Kahski, J. Chromatog., 1960, 3, 425.325 D. N. Harris and F. F. Davis, Biochim. Biophys. Acta, 1960, 40, 373.326 B. W. Grunbaum and P. L. Kirk, Analyt. Chem., 1960, 32, 564.327 V. P. Shvedov, Ten Ten, and A. V. Stepanov, Zhur. analit. Khim., 1960, 15, 16.328 J. N. Van Mekerk and J. F. de Wet, Nature, 1960, 186, 380.329 I,. Erdey, J. Inczidy, and I. Markovits, TaZaNta, 1960, 4, 26.A review has been made of starch gel electrophoresi~.~~434 ANALYTICAL CHEMISTRY.example, adsorption of tin@) solutions enables the column to be used forreduction of iron(m) for titration.Finely-divided particles of stronglybasic anion-exchange resins concentrate at the interface between aqueousand organic liquids, and serve to collect traces from dilute aqueous solutions,the materials being chosen to provide sensitive colour reactions.=OThe general adsorption of 43 cations from hydrochloric acid solution onto a particular resin has been studied, leading to values for their distributioncoefficients in different normalities of acid.331 A similar study has beenmade for various concentrations of hydrofluoric acid.332The major constituents of sea water do not form anionic chloro-complexeswith traces of hydrochloric acid, but many of the trace elements do; thisaffords an efficient and simple method of concentrating trace elements onresin for spectrographic determinati~n.~~~ Resins are also used for the mainconstituents in the control of evaporation processes in the manufacture ofsea salt.=Alkali and alkaline-earth metals are separately and completely elutedfrom an exchange resin by an ammonium formate-formic acidTrace amounts of 36 metallic radioelements, pretreated to ensure particularoxidation states and to form some anionic complexes, can be separated intosix groups by elution with a series of complexing agents at controlled pHand ionic strength.336 Mixtures of bi-, ter-, and quadri-valent metals canbe separated into groups by elution with ethylenediammonium perchloratesolutions of varying concentration, some metals remaining on the column.337The separation of germanium from elements interfering with its deter-mination can more readily be carried out by using a mixed bed column thanby Trace elements in silicate rocks may be concentrated byion-exchange as chloro-complexes before spectrographic determinati~n.~~~Thorium in such materials may similarly be c0ncentrated.m Tellurium(1v)is adsorbed, and then reduced on the column by sulphur dioxide solutionto the element, whereupon other elements may be eluted.The tellurium isthen reoxidised and eluted; the adsorption of iodide and iodate has alsobeen studied.=In the salting-out procedure for separation of organic compounds, astudy has been made for the acetone, butanone, and pentan-%one series, ofthe effect on the distribution ratio of the length of hydrocarbon chain, theeluent salt, and the cross-linking and ionic form of the resin.342 A numberof eluents have been studied for the separation of derivatives of phenol on330 Masatoshi Fujimoto, Chemist-Analyst, 1960, 49, 4; Naturwiss., 1960, 47, 252.3 3 X F.W. E. Strelow, Analyt. Chem., 1960, 32, 1185.332 J. P. Faris, Analyt. Chem., 1960, 32, 520.333 R. R. Brooks, Analyst, 1960, 85, 745.334 G. N. Babatschew, 2. analyt. Chem., 1960, 173, 121.335 Hiroyuki Tsubota and Yasushi Kitano, Bull. Chem. Soc. Japan, 1960, 33, 770.336 W. J. Blaedel, E. D. Olsen, and R. F. Buckianan, Analyt. Chem., 1960, 32, 1866.337 J.S. Fritz and S. K. Karraker, Analyt. Chem., 1960, 32, 957.338 T. R, Cabbell, A. A. Orr, and J. R. Hayes, Analyt. Chem., 1960, 32, 1602.399 R. R. Brooks, L. H. Ahrens, and S. R. Taylor, Geochim. Cosmochim. Acta. 1960,540 J. Korkisch and P. Antal, 2. analyt. Chem., 1960, 173, 126.341 E. Kleemann and G. Herrmann, J . Chromatog., 1960, 3, 275.342 A. Breyer and W. Rieman, 111, Talanta, 1960, 4, 67.18, 162CARTWRIGHT AND WILSON : METHODS OF SEPARATION. 436cation-exchange resins.= Some separations of carbohydrates are possible,and some are not, by using water elution from a cross-linked resin in chloride,carbonate, or bicarbonate form.344 Separations are in order of molecularsize, but are not caused by a molecular sieve effect. The lower aliphaticacids can be separated as their N-2,4-dinitrophenylhydrazides from an acid-form resin by ethyl methyl ketone-acetone-water eluent.=A study of the separation of amino-acids on acid and base forms of anumber of ion-exchange resins, using only water as the eluent, indicates thatcomplete separation of all the common ones might be achieved if a smallnumber of resins of improved characteristics, with low cross-linkages andhigh mechanical rigidity to allow fast flow even when finely divided, wereavailable. The possibility is demonstrated of automatic recording of theamino-acid concentration in the effluent by passing it over an insolublecopper(I1) salt and measuring the enhanced conductivity of the cationiccopper complex.346 Simultaneous automatic monitoring of the effluentsfrom eight ion-exchange columns in the separation of amino-acids is de-s~ribed.~' Special columns and pumps permit high pressures and fast flowrates in amino-acid separations,m and a detailed theoretical approach hasbeen made to the separation, resulting in a simple algebraic expressionconnecting the fundamental phenomena upon which it dependsagTwo unusual ion-exchange materials have been described : zirconiumphosphate 350 has been used in the separation of rubidium and czsium; andalginic acid 351 in the separation of thorium and cerium.Gas Chromatography.-A useful introduction to the theory, development,and applications of gas chromatography has been published.352 It discussescommercial equipment, and lists the products of a large number of manu-facturers.Of interest in connection with general gas-chromatographicequipment is the description of a laboratory machine for producing compactcoils of glass capillary with a wide range of diameter and wall thickness.asThe influence of coils on resolution, marked in a preparative column, isd i s c u s ~ e d . ~ ~ A number of techniques and devices for collectingsamples 355~356 and injecting them 357*358 have been described. ,4 radiant34s Tokuichiro Seki, J . Chromatog., 1960, 4, 6.344 L. Hough, J. E. Priddle, and R. S. Theobald, Chem. and Ind., 1960, 900.845 Tokuichiro Seki, J . Chromatog., 1960, 4, 376.346 D. L. Buchanan and R. T. Markiw, Analyt. Chem., 1960, 32, 1400.347 D. H. Simmonds and R. J. Rowlands, Analyt.Chem., 1960, 32, 259.348 P. B. Hamilton, Analyt. Chem., 1960, 32, 1779.349 P. B. Hamilton, D. C. Bogue, and R. A. Anderson, Analyt. Chem., 1960, 32,350 C. B. Amphlett, L. A. McDonald, J. S. Burgess, and J. C. Maynard, J . Inorg.351 Takeo Takahashi and Shingo Miyake, Bull. Chem. SOC. Japan, 1959, 32, 1324.35* W. Simon, Chimia (Switz.), 1960, 14, 189.353 D. H. Desty, J. N. Haresnape. and B. H. F. Whyman, Analyt. Chem., 1960, 32,354 J. C. Giddings, J . Chromatog., 1960, 3, 520.355 R. C. Palmer, D. K. Davis, and W. Van Willis, Analyt. Chem., 1960, 32,358 W. W. Nawar and I. S. Fagerson, Analyt. Chem., 1960, 32, 1534.357 W. W. Nawar, F. M. Sawyer, E. G. Beltran, and I. S. Fagerson, rlnalyt. Chem.,a5* I,, S , Ettre and N. Brenner, J .Chromatog.. 1960, 3, 524.1782.Nuclear Chem., 1959, 10, 69.302.894.1960, 32, 1534436 ANALYTICAL CHEMISTRY.heater has been used for coiled columns, giving steady or programmedtemperatures and rapid cooling when req~ired.35~The fundamental factors of gas chromatography have received attention.Giddings 360 discusses mathematically the optimum conditions for separation,considering column length, flow rate, temperature, particle diameter,pressure, and time, and for capillary columns the tube diameter and thicknessof liquid layer. The sample-inlet system, distribution coefficient of solute,and amount of liquid in the stationary phase are considered by de Wet andP r e t o r i ~ s , ~ ~ ~ and the choice of carrier gas and quantity of stationary phaseby Loyd et aZ.362 The effects of distribution ratio, viscosity, and amount ofliquid phase are studied by Duffield and Rogers.363 Sen3M makes recom-mendations for determining the optimum operating conditions and repro-ducibility. The effect of temperature, when the principal factor is differencesin vapour pressure between the components to be separated, is discussed byW i ~ e r n a n .~ ~ ~ Experimental evidence of eddy diffusion and pressure-gradient effects has been obtained.366Various solid supports for the liquid phase have been described. Groundunglazed tile (0*2--0.3 mm.) has been used with tritolyl phosphate,367 andthe porous material left after heating a commercial detergent and extractingit with light petroleum was used with various non-polar substrates.368Molecular sieves have been used as packings, alone,369 and for removal ofspecific components before conventional separation.370 There is evidencethat secondary adsorption on such sieves may remove components whichshould pass The use of polyesters as stationary phases isdescribed.372Reduced driftand increased sensitivity in thermal conductivity cells by employing ax.excitation are claimed; 373 techniques are described for reducing the noise inthermal conductivity detectors to the level inherent in the thermistor.374The response of such detectors to changes of gas composition and operatingtemperature has been treated,S75 and it has been shown 376 that measuredresponse values, rather than relative areas, give reduced errors.The re-sponse of thermal conductivity cells to a wide range of organic compounds,Considerable work has been carried out on detectors.359 J. N. Roper, jun., Analyt. Chem., 1960, 32, 447.a60 J. C. Giddings, Analyt. Chem., 1960, 32, 1707.361 W. J. de Wet and V. Pretorius, Analyt. Chem., 1960, 32, 169.36% R. J. Zoyd, B. 0. Ayers, and F. W. Karasek, Analyt. Chem., 1960, 32, 698.363 J. J. Duffield and L. B. Rogers, ANalyt. Chem., 1960, 32, 340.364 B. Sen, Analyt. Chim. Acta, 1960, 22, 130.365 W. A. Wiseman, Nature, 1960, 185, 841.366 J. C. Giddings, S. L. Seager, L. R. Stucki, and G. H. Stewart, Analyt. Chem.,367 V. Luke$, R. Komers, and V. Herout, J . Chvomatog., 1960, 3, 303.368 A. W. Decora and G. U. Dinneen, Analyt. Chem., 1960, 32, 164.370 N.Brenner, E. Cieplinski, L. S. Ettre, and V. J. Coates, J . Chromatog., 1960,S71 L. S. Ettre and N. Brenner, J . Chromatog., 1960, 3, 235.37% W. Meyer zu Reckendorf, 2. analyt. Chem., 1960, 1'45, 350.373 J. R. Purcell and R. N. Keeler, Rev. Sci. Instr., 1960, 31, 304.374 R. Kieselbach, Analyt. Chem., 1960, 32, 1749.375 L. J. Schmauch and R. A. Dinerstein, Analyt. Chem., 1960, 32, 343.376 R. L. Grob, D. Mercer, T. Gribben, and J. Wells, J . Chromatog., 1960, 3, 545.1960, 32, 867.M. KrejEi and K. Tesafik, Coll. Czech. Chem. Comm., 1960, 25, 691.3, 230CARTWRIGHT AND WILSON: METHODS OF SEPARATION. 437and the effect of substituents, have been st~died,~77 and errors due to changesin pressure and flow rate on introduction of the sample have been con-~idered.3~~ A glass ionisation detector can be used without a radiationsource.The effect of argon-nitrogen carrier-gas mixtures on the sensitivityof an ionisation detector has been investigated,380 and a modification 381enables one detector block to be used with both capillary and large columnsup to temperatures of 250". Other methods of detection have been studiedand described. A critical study of increase in sensitivity by catalyticcombustion on heated platinum wire has been made; 382 and there areadvocates of a Tesla discharge detect0r,~8~ the use of a mercury-drop potentio-meter,384 and the employment, in conjunction with a thermal conductivitydetector, of a conventional mass ~pectrometer.~~Statistical evaluation of the usual methods for quantitative measure ofgas-chromatographic curves has been made for areas of various sizes,386 withthe conclusion that none is quite satisfactory.An automatic analogue inte-grator is described 387 which computes and prints, with possible developmentto printing on the appropriate curve, the component concentration value.The development of programmed temperature gas-chromatography con-tinues, and has been studied theoreti~ally.~88,38~,~~0 Simple operatingtechniques are described.3g1 Movement of a heater down the column morethan once at successively higher temperatures improves resolution and com-presses the bands.392 High-temperature separation of metal halides onfused salt substrates is de~cribed,3~3 and an improved sampling method hasbeen devised 394 for use at temperatures up to 500".Only the more generally interesting and versatile applications of gaschromatography will be described.Water in butane, to a limit of 0.2 p.p.m.in a 10-litre sample, has been determined by trapping and then flushing intoa helium stream.395 There have been many applications to the determinationof gases, such as hydrogen396 and its isotopes397-399 in admixture with377 G. R. Jamieson, J . Chromatog., 1960, 3, 464, 494.378 A. Weinstein, Analyt. Chem., 1960, 32, 288.3'9 E. Haahti, T. Nikkari, and E. Kulonen, J . Chromatog., 1960, 3, 372.380 D. Welti and T. Wilkins, J . Chromatog., 1960, 3, 589.3s1 R. Teranishi, C. C. Nimmo, and J. Corse, Analyt. Chem., 1960, 32, 896.382 J.SlAdeeek, Coll. Czech. Chem. Comm., 1960, 25, 636.383 J. C. Sternberg and R. E. Poulson, J . Chromatog., 1960, 3, 406.384 J. Surov?, Chem. Listy, 1960, 54, 263.385 L. P. Lindeman and J. L. Annis, Analyt. Chem., 1960, 32, 1742.386 J. JanPk, J . Chromatog., 1960, 3, 308.387 2. Bohm, J . Chromatog., 1960, 3, 265.388 S. Dal Nogare and W. E. Langlois, Analyt. Claenz., 1960, 32, 767.389 H. W. Habgood and W. E. Harris, Analyt. Chem., 1960, 32, 450.390 J. C. Giddings, J . Chromatog., 1960, 4, 11.391 F. T. Eggertsen, S. Groennings, and J . J. Holst, Analyt. Chem., 1960, 32, 904.392 A. G. Nerheim, Analyt. Chem., 1960, 32, 436.393 R. S. Juvet and F. M. Wachi, Analyt. Chem., 1960, 32, 290.394 H. E. Dubsk? and J. JanAk, J . Chromatog., 1960, 4, 1.3g5 A.A. Carlstrom, C. F. Spencer, and J . F. Johnson, Analyt. Chem., 1960, 32, 1056.Sg6 R. Massart and L. Missa, Bull. Cent. Belge Xtud. et Docum. Eaux, 1960, 43.397 E. M. Arnett, M. Strem, N. Hepfinger, J. Lipowitz, and D. McGuire, Science,898 P. H. Dutch, Analyt. Chem., 1960, 32, 1632.399 F. K. Heumann, U.S. Atomic Energy Comm., Rep. KAPL-970, July, 1953,1960, 131, 1680.Decl. Mar., 1960438 ANALYTICAL CHEMISTRY.nitrogen and other gases; 400-402 of helium and neon,4o3 and of chlorinecontaining other gases.404 Volatile acetylacetonates of a number of metalscan be chromatographed at temperatures well below that of decomposition ;the method is particularly suited to determination of beryllium.405A five-arm stream-splitting device, consisting of a serum cap with in-serted needles, has been usedM6 to bubble the eluent into classificationreagents, which, with retention volume-time, serve to identify components.A prefractionating technique is described 407 using selective chemical re-actions in conjunction with gas chromatography for identification purposes.A rugged flame ionisation detector has been devised 408 for trace-hydrocarbonanalysis.Radioassay of labelled compounds can be carried out 409 duringand after gas chromatography.For separation of organic mixtures with a wide boiling range, a pro-grammed temperature capillary column of thin-walled stainless steel maybe used410 at temperatures up to 240". Higher operating temperatureshave been achieved411 up to 450", and these may succeed in separation ofcompounds with boiling points about 700".By using glass beads as thesolid support, thus minimising adsorption, high-boiling compounds can berapidly eluted at lower temperatures.412Gas Chromatography has been applied to the determination of occludedsolvent in organic compounds,413 and ethanol in blood.414 The determinationof carbon and hydrogen in organic compounds by gas chromatography is ofinterest. The compound is burned to carbon dioxide and water in a streamof oxygen 415 or, mixed with copper oxide and copper, in helium 416 or in abomb with 0xygen.~17 In the first method, the products are passed throughcalcium carbide, and the carbon dioxide and acetylene are frozen out, andsubsequently chromatographed. In the second, after similar production ofacetylene, the products are passed directly to the column, and in the thirdthe water and carbon dioxide in a sample of the combustion products arechromatographed directly.For the first two methods, absolute accuracies are of the order of 0.5%for carbon and 0.1-0-2% for hydrogen. For the third method, they aresimilar for carbon, and about 04370 for hydrogen; all are assessed on alimited number of results..400 E.W. Lard and R. C. Horn, Analyt. Chem., 1960, 32, 878.401 P. Tyou, Inst. Hierro Acero, 1960, 13, 383.41)2 N. S. Torochesnikov and V. A. Seminova, Zhur, przklad. Khim., 1960, 33, 597.403 E. Zielinski, Claem. Analit., 1960, 5, 297.4D4 E. E. Neely, Analyt. Chem., 1960, 32, 1382.4O.5 W. J. Biermann 2nd H.Gesser, Analyt. Chern., 1960, 32, 1525.4O6 J. T. Walsh and C. Merritt, jun., Analyt. Chem., 1960, 32, 1378.407 R. Bassette and C. H. Whitnah, Analyt. Chern., 1960, 32, 1098.408 A. J. Andreatch and R. Feinland, Analyt. Chem., 1960, 32, 1021.409 A. Karmen and H. R. Tritch, Nature, 1960, 186, 150.410 R. Teranishi, C . C. Nimmo, and J. Corse, Analyt. Chem., 1960, 32, 1384.411 B. J. Gudzinowicz and W. R. Smith, Analyt. Chem., 1960, 32, 1767.412 C. Hishta, J. P. Messerly, and R. F. Reschke, Analyt. Chem., 1960, 32, 1730.413 C. E. Childs and E. B. Henner, Chemist-Analyst, 1960, 49, 26.414 B. Chundela and J. JanAk, cas. Lbk. &., 1960, 99, 90.jlj A. A. Duswalt and W. W. Brandt, Analyt. Chem., 1960, 32, 272.416 0. E. Sundberg and C. Maresh, Analyt.Chern., 1960, 32, 274.417 A. M. Vogel and J. J. Quattrone, jun., Analyt. Chenz., 1960, 32, 1754CARTWRIGHT AND WILSON : GRAVIMETRIC ANALYSIS. 439In a number of papers a considerable amount of data is given for par-ticular classes of organic compound. Retention times for 93 hydrocarbonswith various liquid phases are quoted.41* Higher hydrocarbon data aregiven 419 for c,,-~,, (250") and cm-c36 (320-390'). Relative retentiontimes of 44 terpene hydrocarbons and related compounds are given.420 c,-c,, saturated fatty amines have been separated and determined.421 For22 heterocyclic bases and 10 accompanying aromatic compounds in coal tar,elution volumes are given.4226. GRAVIMETRIC AND TITRIMETRIC ANALYSISGravimetric Analysis.-One may not wholly agree with H.N. Wilson'scontention5 that gravimetric methods should if possible be avoided; andperhaps with wider applications of precipitation from homogeneous solutionsome of his more delightful strictures on the methods may lose their point.It is certainly true that there is little development to report in classicalgravimetric techniques, apart from improvements in balances, althoughthere have been many applications of established methods to new problems,naturally inorganic in the main.It is an indication of the progress of analytical chemistry thatin a composite procedure for the analysis of aluminium bronzes,173 whichwould once have consisted of a succession of gravimetric operations lastingseveral days, there is only one such determination, that of silica, and thetotal analysis takes 3 i hours.An investigation has been made of the precipitation of metals by ethyl-,n-propyl-, and n-butyl-arsonic acids.m In many cases precipitation isquantitative.but asolubility correction is needed.Potassium in the presence of ammoniummay be precipitated as the cobaltinitrite, ammonium being masked withformaldehyde.425 Studies have been made of the precipitation of czsiumwith hexachlorotellurous and of ammonium as the tetraphenylboronsalt,427 and optimum conditions are recommended for both.Beryllium has been determined gravimetrically by precipitation with2,2-dimet hylhexane-3,5-dione and with 3-prop ylpent ane-2,4-di0ne,~~, withthe advantage of the very small conversion factor of 0.03096 in each case.The separation of magnesium from sodium and potassium by precipitation asammonium phosphate, as oxalate (from homogeneous solution), and asInorganic.Lithium has been precipitated by using potassium418 13.A. Hively, J . Chem. and Eng. Data, 1960, 5, 237.419 C. G. Scott and D. A. Rowell, Nature, 1960, 18'9, 143.420 W. J. Zubyk and A. 2. Conner, Analyt. Chem., 1960, 32, 912.421 W. E. Link, R. A. Morrissette, A. D. Cooper, and C. F. Smullin, J. Anzer. Oil422 J. Jan5.k and M. HZivnAE, Coll. Czech. Chem. Comm., 1960, 25, 1557.423 R. Pietsch, Mikrochim. Acta, 1960, 539.4 2 4 C. C. Patel and K. N. Vishweshwaraiah, Analyt. Chem., 1960, 32, 202.lz5 A. Holasek, H. Lieb, and M. PeCar, Mikrochim. Acta, 1960, 750.j Z 6 H. A. C . Montgomery, A~zaZyst, 1960, 85, 687.iZ7 F.E. Crane, jun., and E. A. Smith, Chemist-Analyst, 1960, 49, 38.128 E. S. Przheval'skii and L. M. Moisseva, Zhur. analit. Khim., 1960, 15, 117.Chemists' SOC., 1960, 37, 364440 ANALYTICAL CHEMISTRY.oxinate (by both usual and homogeneous methods) has been compared byusing a tracer Co-precipitation is negligible except in the phos-phate method, and in the homogeneous oxine method it is only one-third ofthat in the usual oxine method. An interesting method, applied to thealkaline-earth elements,430 for collecting trace quantities of cations fromsolution involves adding potassium rhodizonate solution, mixing, addingethanol, and allowing the reagent to crystallise. Quantitative collection ofalkaline-earth elements from to 10-16M-solutions is obtained with S070crystallisation of the reagent.The safe minimum temperature for ignition of aluminium precipitates 431to constant weight of A1,0, is shown to be 1200". Gallium and indium maybe determined in presence of each other by precipitating indium, in presenceof excess of oxalate, with diethyldithiocarbarnate and weighing as such ;gallium is determined in the filtrate with 0 ~ i n e .l ~ ~ Thallium has been gravi-metrically determined as the tetraphenylboron compound.432Silica of high purity may be obtained by adding gelatin solution afterprecipitation by a~id.43~ Precipitation of silica, with photometric deter-mination of silicon in the filtrate, is used in rock and mineral analysis.434A standard method has been published for gravimetric determination of leadin steels.435The determination of phosphate as magnesium ammonium phosphatehas been studied, and methods described for eliminating interferences.*Separation from lead is achieved by precipitating bismuth as hydroxide inthe presence of EDTA,437 and separation from a number of metals by pre-cipitation with dimethylglyoxime 438 at pH 11, EDTA being used to keepbasic bismuth salts, and cyanide with EDTA to keep other metals, fromprecipitating.The co-precipitation of 15 metals on precipitates of tellurium obtainedwith sulphur dioxide has been studied 439 and conditions for minimum con-tamination have been established.A new type of reagent, using the sulphon-amide group for chelation , has been investigated ,440 and o-(toluene-P-sulphon-amido)aniline (T-sulphonamidine) is proposed as a virtually specific chelatingagent and precipitant for copper.Copper and nickel can be gravimetrically determined with 3-hydroxyimino-methylsalicylic acid,441 cadmium with l-phenyltetra~oline-5-thione,~~ mer-cury with sodium tetraphenylb~ron,~~ and scandium with mercaptobenzo-429 A.H. A. Heyn and H. L. Finston, Analyt. Chem., 1960, 32, 328.430 H. V. Weiss and Ming G. Lai, Analyt. Chem., 1960, 32, 475.431 0. I. Milner and L. Gordon, Talanta, 1960, 4, 115.432 I. P. Alimarin and I, Krausz, Magyar Kkm. Folybirat, 1960, 68, 262.433 P. Phssera, L. Garzbn RuipQez, and J. Salas Sanceledonio, Inf. Quim. Anal.,434 P. G. Jeffery and A. D. Wilson, Analyst, 1960, 85, 478.435 British Standards Institution, B.S.1121 : Part 41, 1960.436 E. Schulek and A. Endroi-Havas, 2. analyt. Chem., 1960, 174, 90.437 F. W. Lima and A. Abrzo, Analyt. Chem., 1960, 32, 492.438 P. F. Lott and R. K. Vitek, Analyt. Chem., 1960, 32, 391.439 H. Bode and E. Hettwer, 2. anaZyt. Chem., 1960, 173, 285.411 Asit Kumar Ray and Priyadaranjan Rgy, J. Indian Chem. SOL, 1960, 37, 133.442 C. E. Moore and T. A. Robinson, Aqzalyt. Chim. Ada, 1960, 23, 533.443 A. Heyrovsk?, Analyst, 1960, 85, 432.1960, 14, 38.J. H. Billman, N. S. Janetos, and R. Chernin, Analyt. Chern., 1960, 32, 1342CARTWRIGHT AND WILSON : GRAVIMETRIC ANALYSIS. 441thiazo1e.m A detailed study using radiochemical techniques of the pre-cipitation of rare-earth oxalates has been made 445 and optimum conditionshave been described.For precipitation and direct weighing of zirconium with organic reagents,Milner and Edwards 25 recommend mandelic acid or tartrazine; Corsini andGraham 446 advocate also 8-hydroxyquinaldine.Many other reagents ,involving ignition to the oxide, have been put forward for both zirconiumand thorium. Direct weighing is possible of the vanadium precipitate with2-hydroxy-N-naphthylmethylene-ethylamine and with 2-hydroxynaphthald-oxime,a7 and of the niobium precipitate with cinnamylhydroxamic acid,448with very favourable conversion factors.A number of cobalt compounds for use as standards in assessing analyticalmethods have been investigated 449 and three suitable ones are recommended.A tracer technique being used, the best conditions for precipitating cobalt aspotassium cobaltinitrite have been established.&OGravimetric methods form part of a scheme for the separation anddetermination of the platinum metals,226 and the separation of platinumand rhodium from iridium in this scheme has been compared with the classicalmethod by a radio-tracer New gravimetric methods for osmium,using acridine or thiourea, are proposed.a2 Palladium has been determinedby direct weighing of the precipitates with 2-hydroxy-l-naphthaldehydeJa3and with 2-thiophen-trans-a1doxime.aOrganic.Although gravimetry in its widest sense is used in organicanalysis, as in determining loss of weight on extraction, or weight of anisolated constituent, or indirectly by conversion into an inorganic determin-ation , gravimetric methods involving direct precipitation are few.A studyhas been made of the drying temperature of formaldehyde dimedone pre-c i p i t a t e ~ , ~ ~ ~ which are claimed to sublime at 103".Precifiitation from homogeneous solution. Fischer, in studies of nucleationin precipitation reactions J456 emphasises the influence of sites for nucleationalready present in the water or reagents used. He finds that in precipitationfrom homogeneous solution of cadmium and lead sulphides by hydrolysis ofthioacetamide, and of barium sulphate by sulphamic acid, the reagents con-tain sufficient precipitating anion to provide nuclei immediately on mixingwith the cation solution; this is followed by slow growth of precipitatewithout further nucleation.444 T.I. Pirtea, Rev. Chim. (Roumania), 1960, 11, 336.445 K. G. Broadhead and H. H. Heady, Analyt. Chem., 1960, 32, 1603.446 A. Corsini and R. P. Graham, Analyt. Chim. Acta, 1960, 23, 248.447 S. I. Gusev, V. I. Kumov, and E. V. Sokolova, Zhur. analit. Khim., 1960,448 A. I<. Majumdar and A. K. Mukherjee, Analyt. Chim. Acta, 1960, 22, 514.449 A. G. Foster and W. J. Williams, Analyt. Chim. A d a , 1960, 22, 538.450 D. Salyer and T. R. Sweet, Analyt. Chem., 1960, 32, 548.451 K. W. Lloyd and D. F. C. Morris, Talanta, 1960, 7, 117.452 P. Spacu and C. Gheorghiu, Z. analyt. Chem., 1960, 174, 340.453 A. S. Pesis and Z. A. Bitovt, Zh.ur. analit. Khim., 1960, 15, 200.454 S. G. Tandon and S.C. Bhattacharyya, Analyt. Chem., 1960, 32, 194.455 H. Slusanschi, 2. Lebensm.- Untersuch., 1960, 112, 390.456 R. B. Fischer, Analyt. Chem., 1960, 82, 1127; Analyt. Chim. Acta, 1960, 22,15, 180.501, 608442 ANALYTICAL CHEMISTRY.The reactions of metals with thioacetamide have been discussed,a7 anda detailed study has been made of the precipitation of zinc sulphide fromacid solutions by this reagent.&8Homogeneous methods have been applied, generally with the formationof dense, easily-filterable precipitates, and sharper separations from impuri-ties, to the determination of lead as sulphate by hydrolysis of sulphamicacid; 459 to the determination of bismuth as phosphate by hydrolysis ofmetaphosphoric acid,4Go and to the precipitation of bismuth as basic formateand its separation from lead by hydrolysis of urea.461Copper has been precipitated as cuprous tetraphenylborate by reduction,under homogeneous conditions, with ascorbic acid.462 Selective precipitationof silver chloride, bromide, and iodide in crystalline form has been carried outby controlled volatilisation of ammonia.463 A precipitate of crystalline ferricoxide is obtained by hydrolysis of NN-di-(2-hydro~yethyl)glycine.~~Metal oxinates have been precipitated from homogeneous solution byhydrolysing 8-acetoxyquinoline to generate the reagent in s i t ~ c .4 ~ ~ Themethod has been applied to the precipitation of a dense form of thoriumoxinate; 466 for direct weighing the precipitate must be dried at a veryclosely controlled temperature.Titrimetric Analysis.-By far the greatest proportion of publications ontitrimetry has been concerned with applications of known methods tovarious materials, and this is particularly true with chelatometric titrations.In some cases there is the implication that the method is not so well foundedas may appear, and that modification is required with each environment.In some, the modifications themselves are to be noted as of potentially widermerit.The many relatively straightforward applications, even to the mostinteresting of materials, cannot find room in this Report.After brief account of advances in apparatus and general theory, thissection deals with various types of classical titrimetry, then with chelato-metric titrations, and finally with non-aqueous titrations and functional-group determination, which are combined because of the considerableoverlap of the two topics.A simple push-button burette valve has been designed inwhich fast and slow flow are controlled by electromagnets operating a clampon small-bore flexible A precision burette with a high degree ofcontrol over flow-rate and the termination of the titration is described.M8For automatic operatiops there is a pipette which delivers by remote switch-ing and automatically refills.4G9General.457 E.H. Swift and F. C. Anson, Talanta, 1960, 3, 296.458 D. F. Bowersox, D. M. Smith, and E. H. Swift, Talanta, 1960, 3, 282.459 F. Burriel-Marti and M. J. GArate, Rec. Trav. chim., 1960, 79, 495.460 H.H. Ross and R. B. Hahn, Analyt. Chem., 1960, 32, 1690.461 P. F. S. Cartwright, Analyst, 1960, 85, 216.462 D. G. Davis, Analyt. Chenz., 1960, 32, 1321.463 F. H. Firsching, Analyt. Chenz., 1960, 32, 1876.463 E. R. Nightingale, jun., and R. F. Benck, Analyt. Chem., 1960, 32, 566.46i E. D. Salesin and L. Gordon, Talanta, 1960, 4, 75.$66 K. Takiyama, E. D. Salesin, and L. Gordon, Talanta, 1960, 5, 231.457 J. T. Stock and M. A. Fill, Analyst, 1960, 85, 609.Jfid R. A. Chalmers and D. A. Thompson, Analyst, 1960, 85, 226.469 H. V. Malmstadt and G. P. Hicks, Analyt. Chem., 1960, 32, 445CARTWRIGHT AND WILSON : TITRIMETRIC ANALYSIS. 443E. Bishop continues his series of theoretical considerations in analyticalchemistry. He shows that it is frequently necessary to correct simpleexpressions for pH of buffer solutions by taking into account the ionisationof the weak acid or base, and gives graphical data of the conditions underwhich this should operate.470 A simplification of the calculation of asym-metrical titration curves is obtained by considering the difference betweentitrant volume and equivalence point volume, rather than the volume oftitrant added.471 A critical study of acid-base titration errors demonstratesthat only the chemical end-point error is normally significant ; expressionsfor it are deri~ed.~7~ Liteanu and Cormos, in a series of theoretical studieson equivalence point,473 have proposed new and more precise general methodsfor determining the equivalence point in a linear equation, and the coefficientsof asymmetry and equivalence in a potentiometric titration ; the methodsare based on linearising the titration curves before and after the equivalencepoint by the technique of least squares, and using their point of intersection.A general equation has been derived for the equivalence point potential inan oxidation-reduction titration in which no additional equilibria are in-v01ved,4'~ indicating its dependence on concentrations of reagents.A detailed treatment of the colour quality of an indicator transition interms of all the factors affecting its appreciation by an observer *75 has beenextended to cover colorimetric analysis of multicomponent mixtures,calculation of pK of acids, and the formulze and stability constants of complexions .476A new primary standard, cadmium hydrogen N-(hydroxyethy1)ethylene-diamine-NN'N'-triacetate, has been proposed for alltalimetry and chelo-metry; 477 it is stable, non-hygroscopic, and easy to prepare and purify.Reviews have appeared on the titrimetric determination of antimony 478and of ~ u l p h a t e , ~ ~ ~ and on developments in the Karl Fischer procedure.u0Acid-base tifrations.Improvement in the indicator performance ofMethyl Red and Methyl Orange has been found by screening with sulphon-ated phthalocyanine~.~~~ The colour-change characteristics of six pyro-mellitein indicators have been and several new ion-exchange resinindicators, including a universal indicator, have beenDirect determination of free acid in the presence of hydrolysable cationscan be carried out by titration in a solution containing ferric and fluorideions 484 without errors due to hydroxide complexes. The free alkali metals'j70 E.Bishop, Analyt. Chim. Acta, 1960, 22, 16.l i l E. Bishop, Analyt. Chim. Acta, 1960, 22, 101.472 E. Bishop, AnaZyt. Chim. Acta, 1960, 22, 205.' I i 3 C. Liteanu and D. Cormos, Talania, 1960, 7, 18, 25, 32.4i1 A. J. Bard and S. H. Simonsen, J . Chem. Edzcc., 1960, 37, 364.475 C. N. Reilley, H. A. Flaschka, S. Laurent, and B. Laurent, Analyl. Chem., 1960,476 C. N. Reilley and E. M. Smith, AnaZyt. Chenz., 1960, 32, 1233.4i7 J. E. Powell, J. S. Fritz, and D. B. James, Analyt. Chem., 1960, 32, 954.4 7 a M. R. Thompson, Metallurgia, 1960, 61, 283.4ig A.M. G. Macdonald, I n d . Chemist., 1960, 36, 345.480 A. M. G. Macdonald, I n d . Chemist., 1960, 36. 292.481 T. P. Sastry and S. A. Pratt, 111, 2. analyt. Chem., 1960, 174, 359; 175, 182.4x2 J. A. Bishop, Analyt. Chim. Acta, 1960, 22, 117.4xJ L. LdgrAdi, Magyar. KLm. FoZy6irat, 1960, 66, 76.484 A. Moskowitz, J. Dasher, and H. W. Jamison, Jr., AnaZyt. Chem., 1960, 32, 1362.32, 1218444 ANALYTICAL CHEMISTRY.may be determined by a chain of reactions 485 involving controlled hydrolysisof the metal in oxygen, catalytic production of water, absorption of this onphosphorus pentoxide, and titration of the . product. In determiningthe sodium zinc uranyl acetate is dissolved in water and passedthrough an acid ion-exchange column, with titration by sodium hydroxideof the liberated acetic acid.Determination of phosphate and borate to-gether is possible by adjusting the solution to pH 4.5, adding silver nitratesolution, and titrating with alkali to pH 6.0, giving phosphate; collectingthe precipitated silver phosphate, and removing the excess of silver withsodium chloride, refiltering, adjusting the pH to 5.5, and titrating the boratein the presence of glycerol to pH 8.5.Precipitation titrations. Conditions necessary for the use of chelato-chrome indicators in precipitation titrations have been reviewed.& Theperformance as adsorption indicators in argentimetry of fluorescein andsuccinylfluorescein dyes 489 and of pyromellitein compounds 490 has beenstudied.Burns and M~raca,4~1 in using the Volhard titration to determine smallquantities of chloride, have made a detailed study of the determinate errorsin the end-point involving the operator; this is applicable to any back-titration with a visual end-point.Clarification has been made of the reasons for usinga high hydrochloric acid concentration in the Andrews titration of iodine.492Discrepancies in the literature concerning the titrimetric use of chlorite havebeen examined, and its potentialities establi~hed.~~3 A simple method isdescribed * for determining germanium by reduction with hypophosphiteand titration with iodide-iodate to the starch end-point. Determination ofarsenite in the presence of arsenate 495 is based on quantitative oxidation ofarsenite by N-bromosuccinimide with liberation of hydrobromic acid.Thereagent is a crystalline compound soluble in hot water without volatilisation,and arsenite is titrated with it in the presence of iodide to a starch end-point.The preparation and use of standard solutions of bromine monochloride havebeen described.4g0By using mixtures of electrolytic and reducedsilver, a reductor column can be prepared which combines rapid flow ratewith long life : a self-levelling device ensures that the silver is always coveredwith The addition of a ferrous solution to an ammoniacal solu-tion of vanadium(v) or uranium(v1) containing catechol causes rapid reduc-Halogen titrations.Other redox titrations.485 M. Berkenblit and A. Reisman, Analyt. Chew., 1960, 32, 721.486 D.Ceausescu, 2. analyt. Chew., 1960, 176, 1.487 D. C. Cillurn and D. B. Thomas, Analyst, 1960, 85, 922.488 R. Piischel and E. Lassner, Chemist-Araalyst, 1960, 49, 58.489 U. Kapoor and H. L. Nigam, 2. analyt. Chew., 1960, 174, 179, 186.490 J. A. Bishop, Analyt. Chim. Acla, 1960, 22, 221.491 E. A. Burns and R. F. Muraca, Analyt. Chim. Acta, 1960, 23, 136.492 J. J. Kipling and G. Grimes, Talanta, 1960, 5, 278.493 J. Minczewski and U. Glabisz, Talanta, 1960, 5, 179.494 G. J . Abel, jun., Analyt. Chem., 1960, 32, 1886.495 M. 2. Barakat and A. Abdalla, Analyst, 1960, 85, 288.496 E. Schulek and K. Burger, Tulantcz, 1960, 7, 41 ; K. Burger and E. Schulek, ibid.,4B7 J. I. Dinnin, Andyt. Ckim. Acta, 1960, 28, 296.p. 46CARTWRIGHT AND WILSON : TITRIMETRIC ANALYSIS.445tion to (111) and (IV) respe~tively,~~8 the reducing strength exceeding that ofan acid chromous solution. This provides a direct titration with ferroussolutions to potentiometric or amperometric end-points. Quinol may beused in potentiometric titration of copper 499 in the presence of thiocyanate.The use of osmium tetroxide as a general catalyst for oxidations inalkaline medium,500 and the reducing properties of alkaline cerous solutions,501have been described. The Lingane-Karplus method for determiningmanganese@) by potentiometric titration with permanganate in pyro-phosphate medium has been investigated for interferences, and conditionsto avoid them, particularly from chromium, have been established.5o2 Sili-cate minerals are decomposed at room temperature with hydrofluoric acidcontaining vanadium(v) , which is not reduced by fluoride, but which oxidisesiron quantitatively and is thus reduced to vanadium(1v) ; this is not oxidisedby air, and the iron is determined by titrating the excess of vanadium(v)with a ferrous solution.503 Permanganate in the presence of fluoride is usedto determine chromium(1rr) and vanadium(1v).A mixture of silver and manganese nitrates in perchloric acid is used as acatalyst 504 in the determination by cerate of mercury(1).The mechanismof oxidation by cerate-chromate reagent, more powerful than chromate butmore stable at higher temperatures, has been studied.505A precise method is described 506 for determining vanadium by oxidationto vanadium(v), reaction with a weighed excess of ferrous ammonium sul-phate, and back-titration with dichromate.The use of manganate solutionsin oxidation titrimetry continues to receive study, by Issa and Allam 507and by den Boef et d 6 0 8 Molybdenum(v1) may be determined by titrationwith molybdenum(II1) , resulting in molybdenum(v) ; interferences have beenstudied.509 A method which is satisfactory for natural uranium gives lowresults for 235U; it is suggested that a- and y-radiation induce atmosphericoxidation.510Mercuric solutions can be standardised by passing hydrogen sulphide intothem and titrating the liberated acid with alkali to a Methyl Purple end-point.511 Aromatic boron compounds can be titrated with mercuric solu-tions with potentiometric end-point Small amounts ofsulphate have been determined by reduction to sulphide and titration withmercuric acetate, diphenylthiocarbazone being used as indicat0r.~13 The498 J.W. Miller, Talanta, 1960, 4, 292.499 M. PavlikovA and J. Zqka, 2. analyt. Chem., 1960, 172, 321.500 F. Solymosi and J. Csik, Chemist-Analyst, 1960, 49, 12.601 N. H. Furman and A. J. Fenton, jun., Analyt. Clzem., 1960, 32, 745.502 W. G. Scribner, Analyt. Chem., 1960, 32, 966, 970.503 A. D. Wilson, Analyst, 1960, 85, 823.504 W. H. McCurdy, Jr., and G. G. Guilbault, Analyt. Chem., 1960, 82, 647.506 N. N. Sharma and R. C. Mehrotra, 2. analyt. Chem., 1960, 173, 395.606 W. C. Dietrich, U.S. Atomic Energy Comm., Rep. Y-1294, Mar., 1960.I. M. Issa and M. G. E. Allam, 2.analyt. Chem.. 1960, 175, 103, 421.508 G. den Boef and A. Daalder, 2. analyt. Chem., 1960, 172, 360; H. L. Polak and509 A. I. Busev and L. I. G p , Zhur. analit. Khim., 1960, 15, 191.tilo J. Rynasiewicz, R. F. Dufour, and D. P. Stricos, Analyt. Chem., 1960, 32, 1048.511 G. Matsuyama, Chemist-Analyst, 1960, 49, 21.512 A. Heyrovskq, 2. analyt. Chem., 1960, 173, 301.61s P. G. Quartermain and A. G. Hill, Analyst, 1960, 85, 211.G. den Boef, ibid., 1960, 175, 265446 ANALYTICAL CHEMISTRY.formation of undissociated mercuric cyanide is the basis of a method fordetermining cyanide, or conversely mercury(I1) , by using Variamine Blue asindicator.614 The same indicator is used in the mercurimetric determinationof chloride, bromide, and mercury(1) .515Miscellaneous titrations.The total of silver and mercury in smallamounts may be determined by titration with thiofiuorescein to a pale bluecolour; silver alone is determined by masking the mercury.516 The titrationof mercury(I1) by sodium tetraphenylboron in neutral or slightly acid solutionto a persistent turbidity is described.517 Heterometric determination maybe made of platinum, palladium, and gold by titration with phenanthrolineand with papa~erine.~l*Chelatometric titrations. A review has been published, with 121 refer-ences, of the determination of metals by EDTA.519 Reagents other thanEDTA have been studied. A comparison is made 520 of the performance ofdiethylenetriaminepenta-acetic acid with that of EDTA, lJ2-diaminocyclo-hexanetetra-acetic acid, 1,2-di-(2-aminoethoxy)ethane-NNN"'-tetra-aceticacid, triaminotriethylamine, and triethylenetetramine.The first-namedtitrant is claimed to have advantages in certain cases. The use of Calci-chrome in determining calcium in the presence of magnesium, strontium, andbarium has been mentioned on p. 417. Unithiol (2,3-dimercaptopropane-sulphonate) has been used 521 to determine zinc, Eriochrome Black T beingused as indicator.Photochemical reduction of dyes by free EDTA, but not by metal-EDTAcomplexes, has been used to determine e n d - p o i n t ~ . ~ ~ ~ The titration iscarried out under intense lighting from a projector, and although there issome fading during the titration, the eye appreciates only the sudden dis-charge of colour at the finish.Lucigenin and lumino1523 have been com-pared as chemiluminescent indicators, and the qualities as fluorescent indi-cators of some umbelliferone and hydroxyxanthone corn pound^,^^^ 525 and ofthree EDTA analogues derived from 3,3'-disubstituted benzidines 526 havebeen studied.A number of new dye indicators have been studied for particular EDTAdeterminations: Omega Chrome Green BLL (C.I. Mordant Green 29) 527for aluminium; Omega Chrome Fast Blue 2G (C.I. Mordant Blue 44) 528for magnesium, calcium, and manganese; Solochrome Green V (C.I. Mor-514 2. Gregorowicz and F. Buhl, 2. analyt. Chem., 1960, 173, 115.515 2. Gregorowicz and J. Stoch, 2. analyt. Chem., 1960, 173, 383.516 M. Wrodski, Chem. Analit., 1960, 5, 289.518 M.Bobtelsky and M. M. Cohen, Analyt. Chim. Ada, 1960, 22, 532; 23,42.51s 0. Borchert, Chem. Tech. (Berlin), 1960, 12, 332.520 E. Wanninen, Acta Acad. Aboensis, Math. Plays., 1960, 21, 1.521 L. A. Vol'f, Zavodskaya Lab., 1960, 26, 271.522 J. Joussot-Dubien and G. Oster, Bull. Soc. chim. France, 1960, 343.523 L. Erdey and I. BuzAs, Analyt. Chim. Acta, 1960, 22, 524.624 J. H. Eggers, Talanta, 1960, 4, 38.6a5 D. H. Wilkins, Talanta, 1960, 4, 182.62e R. Belcher, D. I. Rees, and W. I. Stephen, Talanta, 1960, 4, 78.527 A. A. A. El Raheem, A. S. Moustafa, and A. A. Amin, 2. anatyt. Chem., 1960,528 A. A. A. El Rahecm, A. A. Amin, and A. S. Moustafa, 2. analyt. Chem., 1960,A. Heyrovsk9, Analyt. Chim. Ada, 1960, 22, 405.175, 19.172, 347CARTWRIGHT AND WILSON : TITRIMETRIC ANALYSIS. 447dant Green 15) 5z9 for zinc and manganese; Acid Alizarin SN (C.I. MordantBlack 25) and Acid Alizarin SE (C.I.Mordant Black 10) 530 for calcium.Some quinalizarin derivatives have also been studied 531,532 as metallo-chrome indicators, structural requirements of azo-dyes for calcium andmagnesium have been determined,5s and azo-compounds have been in-vestigated as indicators for calcium,534 for thorium, zirconium,and iron,5% for copper, zinc, cobalt, nickel, and lead,537 and for 13 metalsfor which procedures are given.=8 Derivatives of indophenol have beenused for thorium, iron, bismuth, and scandium,539 of naphthoic acid foriron,M and for aluminium, thorium, and zirconiurn,%l and of toluic acid foriron, thorium, and zirconium.a2Jablonski and Johnsona have examined and listed the masking pro-perties of acetylacetone in EDTA titrations; it may be used in variousdeterminations to mask beryllium, aluminium, palladium, iron, uranium,and molybdenum, directly, or by extraction, or by precipitation.Theuse of acetate buffer with and without the addition of complex-formingcompounds has been compared with that of other buffers for EDTAtitrations.mA further study has been made of the titration of calcium, magnesium,and manganese with EDTA, with use of Eriochrome Black T and murexide,202and of magnesium interference in determination of calcium.545 The inter-ference of phosphate in the determination of calcium has been eliminated byback titration with calcium 5469547 or with zinc.548Few metals have escaped the search for new applications of the EDTAtitration: reference must be made to more specialised or extensive sourcesfor the work which has been done.A final and interesting development ofchelatometric titrations is to the indirect determination of organic com-pounds via metal derivatives. Oleic acid is determined through the excessof calcium above that required to form its salt ; 549 derivatives of thiourea willyield cadmium sulphide with cadmium-EDTL4 complex, and the liberated529 A. M. Amin, H. Khalifa, and A. S. Moustafa, 2. analyt. Chem., 1960, 173,530 R. A. Close and T. S. West, Analyt. Chim. A d a , 1960, 23, 261.531 E. G. Owens, 11, and J. H. Yoe, Analyt. Chim. Acta, 23, 321.532 S.Stankoviansky, V. Podany, F. Jassinger, and M. Majer, Chenz. Zvesti, 1960,14,533 H. Diehl and J . Ellingboe, Analyt. Chem., 1960, 32, 1120.534 F. Lindstrom and H. Diehl, Analyt. Chem., 1960, 32, 1123.535 M. R. Zaki and K. Shakir, 2. analyt. Chem., 1960, 174, 274.536 A. K. Majumdar and C. P. Savariar, 2. analyt. Chem., 1960, 174, 197..537 B. S. Jensen, Actu Chem. Scand., 1960, 14, 927.538 G. Guerrin, M. V. Sheldon, and C. N. Reilley, Chemist-Analyst, 1960, 49, 36.538 V. Svoboda, L. Dorazil, and J. Korbl, Coll. Czech. Chem. Comm., 1960, 25,540 C. S. Pande and T. S. Srivastava, 2. analyt. Chem., 1960, 172, 356.Ir** C. S. Pande and T. S. Srivastava, 2. analyt. Chem., 1960, 173, 195.C. S. Pande and T. S. Srivastava, 2. anaZyt. Chem., 1960, 175, 29.543 W.2. Jablonski and E. A. Johnson, Analyst, 1960, 85, 297.W. Berndt and J. Sara, Talanta, 1960, 5, 281.jq5 J. C. van Schouwenburg, Analyt. Chem., 1960, 32, 709.546 T. H. Kamal, J . Agric. Food Chem., 1960, 8, 156.547 T. B. Coolidge, Analyt. Biochem., 1960, 1, 93.548 A. D. Ince and W. A. Forster, Analyst, 1960, 85, 608.54g hT. Antonacci, Chimica e Industria, 1960, 42, 375.138.265.1037448 ANALYTICAL CHEMISTRY.EDTA is titrated with calcium; 550 mepacrine is precipitated by KCdI, andthe excess of cadmium is titrated.551Non-aqueous titrations and fanctional-group determination. General pro-cedures in non-aqueous titrimetry have been described for weak acids inisopropyl alcohol with tetra-n-butylammonium hydroxide in isopropylalcohol as titrant; 552 for bases in glacial acetic acid-acetic anhydride,or methyl cyanide, by using perchloric acid in acetic acid as directtitrant, or by back-titration with sodium acetate in acetic a ~ i d .~ ~ Organic salts can be titrated in ethanol containing phenol with perchloricacid in d i o ~ a n , ~ ~ ~ or, for some cases, in acetic acid with a mixture of chloro-aluminium isopropoxide and its hydr~chloride.~~' Some of the abovemethods use a photometric finish; most employ visual indicators. In non-aqueous potentiometric titrations involving a high ratio of benzene tomethanol, or in dimethylformamide, the addition of lithium chloride hasbeen found658 to increase the stability of pH meters and to increase therate of change of potential near the end-point.It cannot be used in acidicsolvents.The determination of functional groups has been reviewed.= Acetylgroups in acetylated polyvinyl alcohol are determined titrimetrically afterhydrolysis by sodium hydroxide in n-propan01.G~ In an investigation ofthe Zeisel method 560 it was found that only normal primary alkoxyl groupscould be quantitatively dealt with; isomers of propoxy- and butoxy-groups,and propylene glycol compounds and glycerol gave varying results. Theuse of a constant amount of formic acid in the Zeisel titration leads to animprovement in precision; 561 sodium antimony1 tartrate solution is used forscrubbing.The interference of acetophenone in the determination of a number ofalcohols by acetylation has been studied a t varying reaction ternperat~res.~~~Acid-catalysed acetylation in ethyl acetate is used in the determination ofphenols, thiols, and amines, and in some mixtures, depending on the rate ofreaction.563 A study has been made of the acidities of 27 phenols and 17other non-carboxylic organic acids in pyridine, and these are compared withpublished aqueous pKa values.564Glycol ethers are decomposed by hydriodic acid to give a mixture of550 B.Budginsk?, E. VaniCkovA, and J. Korbl, Coll. Czech. Chem. Comm., 1960, 25,551 Yuan-Yau Chou, Jing-Ling Chen, and Ju-Cheng Hsii, Acta Pharm. Sinica, 1960,553 L. E. I. Hummelstedt and D. N. Hume, Analyt. Chew., 1960, 32, 576.554 L. Serrano-Berges, Inf. Quim. Anal., 1960, 14, 41.555 H. Ellert, T. Jasihski, and K.Marcinkowska, Acta Polon. Pharm., 1960, 17, 29.558 R. Vasiliev, E. Sisman, M. Jew, and I. Chialda, Revista Chim., Bucharest, 1960,557 I. Simonyi and G. Tokk, Magyar Kim. Folybirat, 1960, 66, 74.558 E. L. Grove, Talanta, 1960, 4, 205.559 D. Pristavka, Chem. Zvesti, 1960, 14, 472.580 W. J. Kirsten and S. K. Nilsson, Mikrochim. Acta, 1960, 983.561 B. BudZSinskq and J. Korbl, Mikrochim. Acta, 1960, 369.582 J . B. Lal, A. P. Mathur, and V. M. Patwardhan, J . Oil Technol. Ass. India,563 G. H. Schenk and J . S. Fritz, Analyt. Chern., 1960, 32, 987.. x 4 C. A. Streuli, Analyt. Chem., 1960, 32, 407.456.*' '& L. E. I. Hummelstedt and D. N. Hume, Analyt. Chem., 1960, 32, 1792.11, 347.1968 (1959), 14, 9CARTWRIGHT AND WILSON TITRIMETRIC ANALYSIS. 449ethyl iodide and ethylene; the ethyl iodide is determined titrimetrically withsilver nitrate, and the ethylene volumetrically in a nitrometer.= Some1,Z-glycols and polyols may be determined through the aldehyde formed onperiodic acid oxidation.566Acetal, ketal, and vinyl ethers are determined by hydrolysis with hydro-bromic acid to carbonyl compounds, followed by oximation and determin-ation of the excess of hydroxylamine with potassium ferricyanide ; 567advantages of the method are discussed.Iodometric titration of excess of2,4-dinitrophenylhydrazine has been used to determine aldehydes andketones.568 Acid chlorides may be determined by the amount of alkalirequired to saponify the ester formed with anhydrous ethanol,56g or by non-aqueous titration with cyclohexylamine in tetrahydrofuran, with a potentio-metric e n d - p ~ i n t .~ ~ ~ The micro-determination is described 571 of azo- anddiazonium compounds and of nitro-arylhydrazines by titration with titanouschloride. Thiols 572 and thiourea and its derivatives 573 may be determinedin the presence of sulphide by a mercurimetric titration.Epoxides in aqueous or organic solutions will react with dodecanethiol,and the excess of reagent can be titrated with iodine; 574 in the determinationof terminal epoxides, particularly styrene oxide, with sodium thiosulphate,the alkali liberated is neutralised in situ by adding magnesium sulphate.The gelatinous magnesium hydroxide is dissolved in excess of acetic acid,and the excess is titrated.575Degree of unsaturation of fats and oils is determined by hypochlorousacid in the form of acidified commercial bleaching solution.576 Unsaturatedpolyesters are treated, after hydrolysis, with bromine monochloride, asbromate-hydrochloric acid mixture, in determining unsaturation ; iodide isthen added and titration performed with thio~ulphate.~~~Belcher et ad.have continued their series on submicro-methods for theanalysis of organic compounds 578 with methods of determining tertiarynitrogen by use of ion-exchange resin, using substitution to produce thequaternary ammonium iodide, which on the column gives titratable base ;and with the direct potentiometric titration, or back-titration using visualindicators, of carboxyl compounds in aqueous alcohol.Non-aqueous titrations have been used in a wide range of other organicdeterminations. Petroleum nitrogen bases can be selectively acetylated inglacial acetic acid; primary and secondary amines cannot then be titrated565 G, Kainz, Mikrochim. Acta, 1960, 254.b66 L.Maros and E. Schulek, Acta China. Acad. Sci. Hung., 1960, 22, 359.567 B. BudBSinskj. and J. Korbl, Mikrockim. A d a , 1960, 697.568 V. Hamann and A. Herrmann, Deut. Lebensm.-Rundschau, 1960, MI, 95, 133.560 K. Burger and E. Schulek, Talanta, 1960, 4, 120.570 L. J. Lohr, APzalyt. Chem., 1960, 32, 1166.571 J. V. Earley and T. S. Ma, Mikrochim. Acta, 1960, 685.572 M. Wrofiski, Analyst, 1960, 85, 526.573 M. Wroriski, 2. analyt. Chem., 1960, 174, 3.574 B.J. Gudzinowicz, Analyt. Chem., 1960, 32, 1520.575 B. D. Sully, Analyst, 1960, 85, 895.676 R. Basu Roy Choudhury, J . Amer. Oil Chemists' SOC., 1960, 37, 198.577 K. M. GnSger, I. V. Szmrecsinyi, and E. M. Bodi, Magyar Kbm. Lafijla, 1960,578 R. Belcher, M. K. Bhatty, andT. S. West, J., 1960, 2473; R. Belcher, L. Serrano-15, 72.Berges, and T. S. West, ibid., p. 3830.REP.-VOL. LVII 450 ANALYTICAL CHEMISTRY.with perchloric acid, while tertiary amines, which are not acetylated, can bedetermined.57g Amidopyridine in chloroform may be titrated with per-chloric acid in dio~an.~~O Phosphoranes 581 and certain alkaloids 582 can bedetermined by acetic acid-perchloric acid methods. The relative basicityof a number of substituted phosphines has been determined by titration innitromethane and methanol-water solvents.5s37.DETERMINATION OF ELEMENTS IN ORGANIC COMPOUNDSA review of developments in organic analysis 584 includes the determin-ation of elements. The micro-analyst's dream has been described: 585an automatic combustion apparatus suitable for micro- and semimicro-determination of carbon and hydrogen (classical or rapid), halogens, sulphur,and nitrogen (several methods), and which can be used, it is claimed, for anytype of organic compound, with combustion taking 5-6 minutes. Moretypes of Schoniger flask are described; one 5*6 is suitable for carbon deter-mination; the sample in a porcelain boat is ignited by a heated platinumgauze, and the carbon dioxide precipitated as barium carbonate, which isdissolved in acid, the excess of which is back-titrated.It can also be usedfor determination of hydrogen. A drying apparatus for organic compoundsis de~cribed.~'The mechanism of oxidation of organic compounds on heated metaloxides in the absence of oxygen has been studied,5s7 and the use of copper,nickel, and cobalt oxides in elementary analysis is discussed.588 Theefficiency of 28 combustion catalysts has been studied for a mixture ofmethane and oxygen.589In rapid automatic traverse of the movablefurnace, the effect of explosion of the sample can be overcome by using asilver-manganese dioxide catalyst in plac; of part of the silver column.590With 60-mg. samples of solid fuels, a flow-rate of 50 ml. per minute, and afurnace temperature of 1050", the standard deviations of duplicate analyseswere &O.llyo for carbon and &o.05y0 for hydrogen.591In fluorine-containing compounds, interference is overcome by attachinga 120-mm. layer of sodium fluoride, between silver wool plugs and kept at270" rJr lo", to the outlet end of the rapid train.592 The simultaneous deter-Caybon and hydyogen.57s s.W. Nicksic and s. H. Judd, Analyt. Chem., 1960, 32, 998.580 R. Vasiliev, V. Scintee, and I. Chialda, Revista Chim., Bucharest, 1960, 11, 347.581 S. T. Ross and D. B. Denney, Analyt. Chem., 1960, 32, 1896.582 S. M. Tuthill, 0. W. Kolling, and K. H. Roberts, Analyt. Cham., 1960, 32, 1678.583 C . A. Streuli, Analyt. Chem., 1960, 32, 985.584 M. Pesez and M. Legrand, Bull.SOC. chim. France, 1960, 453.585 F. Vojtikh, Chem. pumsyl, 1960, 10, 135.586 F. W. Cheng and C. F. Smullin, Microchem. J., 1960, 4, 213.587 G. Kainz and H. Horwatitsch, 2. analyt. Chem., 1960, 175, 166; 176, 17; Mikro-588 W. J. Kirsten, 2. analyt. Chem., 1960, 174, 282.589 J. HorAEek, J. Korbl, and V. Pechanec, Mihrochim. Acta, 1960, 294.590 L. Dorfman and G. I. Robertson, Analyt. Chem., 1960, 32, 1721.m* W. Radmacher and A. Hoverath, Brennstoff-Chem., 1960, 41, 52.593 P. R. Wood, Analyst, 1960, 85, 764.chim. Acta, 1960, 917CARTWRIGHT AND WILSON: ELEMENTS IN ORGANIC COMPOUNDS. 451mination of carbon, hydrogen, and nitrogen is described; 593 the nitrogendioxide is absorbed in two tubes containing silica gel impregnated with asolution of potassium dichromate in sulphuric acid, between layers ofanhydrone, inserted between the water and the carbon dioxide absorber.The water content of magnesium perchlorate can be determined by arapid and simple method based on temperature rise on dissolution; j8 thestorage of the salt is discussed.A number of acid chlorides have beenexamined as hydrolytic agents for the determination of water in gas~treams.5~4 Pp-Dimethylglutaryl chloride is the best, but, being somewhatvolatile, requires a cooling trap. The p-ethyl-p-methyl compound is muchless volatile, but gives more variable results.A development of the determination of carbon by conductivity measure-ments is reported,595 and a manometric apparatus for carbon and hydrogenis described.596Nitrogen. A comparison has been made of the Kjeldahl and the Dumasmethod.597 The decomposition of metal cyanide and thiocyanate complexesfor Kjeldahl determination was more reproducible and complete by a sealed-tube method; 598 a sealed-tube digestion is efficient for digestion of rocks andsilicate minerals.47 Analysis of boron nitride for nitrogen is carried out byfusing the sample in a stream of nitrogen with lithium hydroxide in a silverthimble.The evolved ammonia is absorbed in boric acid and titrated.5wFor the titration of ammonia absorbed in boric acid, sulphamic acid is usedwith Methyl Red-Alphazurin (C.I. Acid Blue 9) as indicator.m A photo-metric finish, using Nessler reagent, is used for very small quantities ofnitrogen.601Two simple versions of the rapid Dumas apparatus have been de-scribed.602s603 The gas flow in such an apparatus can be checked by amplify-ing the sounds from the bubble-counter.604 Catalytic oxide fillings forthe Dumas determination are propo~ed.~~-~O~ In the determination ofnitrogen in very small samples (max.0-5 mg.) it was found that reproducibleblanks could be obtained by careful control of the carbon dioxide rate.608A simple method of calibrating the nitrometer is described.mOxygen. A modified method is given for purifying the nitrogen gasstream, and the oxygen content in the determination is obtained from the693 E. I. Margolis and A. G. Shevkoplyas, Vestn. Moskov. Univ., 1960, 53.594 R. Belcher, L. Ottendorfer, and T. S. West, Talanta, 1960, 4, 166.595 W.Stuck, Mikrochim. Acta, 1960, 421.5913 R. L. Scott, J. E. Puckett, H. A. Price, M. D. Grimes, and B. J. Heinrich, Analyf.597 H. Hiibsch and K. Nehring, 2. analyt. Chem., 1960, 173, 278.598 €3. Jaselskis and J. G. Lanese, Analyt. Chim. Acta, 1960, 23, 6.~9 J. D. Cosgrove and E. C. Shears, Analyst, 1960, 85, 448.6oo 0. I. Milner and R. J. Zahner, Analyt. Chem., 1960, 32, 294.601 H. Roth, Mikrochim. Acta, 1960, 663.G. M. Gustin, Microchem. J., 1960, 4, 43.603 R. L6vy and B. Cousin, Mikrochim. Acta, 1960, 864.Oo4 K. Eder, Mikrochim. Ada, 1960, 197.605 M. VeEeFa and L. Synek, Mikrochim. Acta, 1960, 208.606 G. Kainz and H. Horwatitsch, 2. analyt. Chem., 1960, 175, 272.607 T. S. Gore and A. S. Kulkami, Mikrochim. Acta, 1960, 559.GO8 G.Gutbier and M. Boetius, Mikrochim. Acta, 1960, 636.6oo E. Stehr, Microchem. J., 1960, 4, 207.Chiin. Acta, 1960, 23, 428462 ANALYTICAL CHEMISTRY.decrease in weight of the " anhydro-iodic acid." 610 The determination oftraces of oxygen is described.611HaZogens. The determination of chlorine after combustion in a flaskhas proved a popular method. Haslam et al. have developed the method toinclude electrical firing of the sample and automatic titration.612 Methodsof finish are critically discussed,613 and a spectrophotometric determinationdescribed.614 In determining chlorine or bromine and sulphur simultane-ously, the latter is titrated with barium perchlorate, and the former withsilver perchlorate in 80% isopropyl alcohol, with dichlorofluorescein asindicator .615A two-stage furnace is described for better control in determining halo-gens by the conventional combustion method.616 After combustion in anoxygen stream, a new method of finish is proposed: the gases pass throughsolid silver iodide at 200°, and the liberated iodine is absorbed in sodiumhydroxide solution, and amplified before deterrninati~n.~~' The use ofsodium nitrite in the final determination is discussed.618Methods of decomposing the sample for halogen determination includefusion with magnesium (errors due to production of elementary carbon arediscussed) ,619 fusion with potassium permanganate powder in a sealedtube,620 and fusion with potassium in a bomb 621 and in an open tubecovered with a layer of glass beads, through which the molten potassiumflows .G22The oxy-hydrogen flame decomposition has been used for chlorine,623but more particularly for fluorine.6u-626 Fluorine in polymers has beendetermined by fusion with sodium in a nickel crucible, destroying the excesssodium and passing the aqueous solution through an ion-exchange column,with titration using alkali.627SzcZpkur.Flask combustion is again the most popular method ofdestroying the organic matter.6B*629 Three methods of finish have610 Satoshi Mizukami, Tadayoshi Ieki, and Kazue Numoto, Mikrochzim. Acta, 1960,S1l I. J. Oita, Analyt. Chim. Actu, 1960, 22, 439.613 E. C. Olson and A. F. Krivis, Microchewz. J., 1960, 4, 181.614 D. J. Lisk, J . Agric. Food Chem., 1960, 8, 119.615 G.Giesselmann and I. Hagedorn, Mikrochim. Acla, 1960, 390.616 E. W. Seefield and J. W. Robinson, Analyt. Chim. Actu, 1960, 23, 301.617 E. Meier, Mikrochim. Acta, 1960, 204.618 W. J. Kirsten, Mikrochim. Acta, 1960, 272.619 J. Yenik, M. JureEek, and V. Patek, Coll. Czech. Chem. Comm., 1960, 25, 1450.620 A. A. Abramyan and R. S. Sarkisyan, Ref. Zhur., Khirua., 1960, Abstract No.621 V. K. Bukina and M. Y. MoIzhes, Ref. Zhur., Khim., 1960, Abstract No. 13,143.622 L. MAzor, L. Erdey, and T. Meisel, Mikrochim. Acta, 1960, 412, 417.823 H. V. Malmstadt and J. D. Winefordner, Analyt. Ckem., 1960, 32, 281.624 D. C. Hoel, D. F. Fanale, and R. 0. Clark, Analyt. Chim. Acta, 1960, 23, 83.625 S. A. Bartkiewicz and J. W. Robinson, Analyt. Chim. Acta, 1960, 22, 427.6zE N.E. Gel'man, M. 0. Korshun, and K. I. Novozhilova, Zhur. analit. Khim.,627 E. Schroder and U. Waurick, Plaste u. Kautsch., 1960, '7, 9.628 A. Steyermark, E. A. Bass, C. C. Johnston, and J. C . Dell, Microchem. J., 1960,629 J. P. Dixon, TaEanta, 1960, 4, 221.183; Satoshi Mizukami and Tadayoshi Ieki, ibid., 1960, 188.J. Haslam, J. B. Hamilton, and D. C. M. Squirrell, Analyst, 1960, 85, 556;J. AfipZ. Chem., 1960, 10, 97.34,568.1960, 15, 222.4, 65CARTWRIGHT AND WILSON : SPECTROSCOPIC ANALYSIS, 453been compared.6m A hydrogenation method is described for sulphur inpetroleum.631Other elements. Selenium is determined by combustion to seleniumdioxide, and iodometric determination.632 Boron, after flask combustion,is determined by mannitol to a visual 633 or potentiometric end-point.Phosphorus, again after flask combustion, is titrated as orthophosphate withceric solution, Eriochrome Black T being used as i n d i c a t ~ r , ~ ~ or measuredas reduced phosphomolybdate complex.636 Loss of phosphorus in the flaskcombustion, due to retention of carbon on the platinum gauze, can be over-c0me.~37 Mercury can be determined simultaneously with carbon, hydrogen,and halogen, by increase in weight of a silver absorber.6388.SPECTROSCOPIC ANALYSISThis section deals with progress in analytical methods which are based onmeasurement of electromagnetic radiation emitted or absorbed by a sample.It excludes, therefore, mass spectroscopy, which uses a much wider inter-pretation of the term spectrum, and is properly an electrical method.Thesection is divided into emission spectroscopy, which embraces also flamephotometry, fluorimetry, and X-ray methods; and absorption spectroscopy,which is sub-divided according to the wavelength region, and includesatomic absorption spectroscopy.Emission Spectroscopy.-The use and effect of special atmospheres inspectral analysis has been d i s c u ~ s e d . ~ ~ In a study of matrix effects inspectrographic discharges ,640 ratio changes were found to be due to temper-ature changes in the discharge, and an equation was derived from whichsuitable conditions for matching line pairs could be defined. The effects ofinteraction between calcium, barium, phosphorus, and zinc, in their spectro-chemical determination in lubricating oils, has been examined by a statistic-ally-designed study 641 which indicated techniques to overcome the errorsproduced. The analytical possibilities of emission work in the Schumannregion (below 2000 A) have been described,a2 together with techniques forminimising the difficulties encountered.Considerable attention has beengiven to the analysis of solutions. An investigation has been made of theinfluence of various spraying techniques into the arc and in conjunctionwith rotating electrodes,* and of improved rotating disc electrodes.=630 H. Soep and P. Demoen, Microchem. J., 1960, 4, 77.631 E. C. Schluter, jun., E. P. Parry, and G. Matsuyama, Analyt. Chem., 1960,32,413.63a E. Meier and N. Shaltiel, Mikvochinz.Acta, 1960, 580.6s8 S. I. Obtemperanskaya and V. N. Likhosherstova, Vestn. Moskov. Univ., 1960,57.634 S. K. Yasuda and R. N. Rogers, Microchem. J., 1960, 4, 156.635 R. Puschel and H. Wittmann, Mikrochim. Acta, 1960, 670.1336 S. J. Gedansky, J. E. Bowen, and 0. I. Milner, Analyt. Chem., 1960, 32, 1447.637 A. Dirscherl and F. Erne, Mikrochim. Acta, 1960, 775.638 M. 0. Korshun, N. S. Sheveleva, and N. E. Gel’man, Zhur. anaZit. Khinz., 1960,639 R. Farskjr, Hutn. Listy, 1960, 15, 548.640 A. J, Frisque, Analyt. Chem., 1960, 32, 1484.641 E. L. Gunn, Analyt. Chem., 1960, 52, 1449.642 G. Milazzo, R.C. Ist. Su?. Sanit., 1960, 23, 133.643 I. A. Voinovitch, Chem. Analit., 1960, 5, 86.644 W. Guttmann, H. Becker, and G. Muller-Uri, Naturwiss., 1960, 47, 128,645 H.J. Philcox, Spectrochim. Acta, 1960, 16, 384.15, 99454 ANALYTICAL CHEMISTRY.Among the very many applications of emission spectroscopy to metals isa method for complete analysis of complex mixtures of the rare-earthelements 646 which gives simultaneous determination of all of them some8 or 10 times more rapidly than by other spectrographic methods; it isbased on selection of homologous pairs in con junction with progressiveweakening of the spectrum.Spectrographic emission has been applied to the determination of gaseouselements in metals. A method is describedJM7 with discussion of the factorsinvolved, for determining oxygen in vanadium by using an arc discharge inargon.A direct procedure has been developed for analysis of semiconductor-grade silicon carbide 648 using selective volatilisation of impurities, whilesuppressing that of the silicon carbide.Limitation of sparking to a verysmall area of a metallic sample by using an insulating varnish has a numberof application^.^^ Fractional distillation from a graphite electrode, withcondensation of the fractions directly on to the electrode, increases the limitof detectability of many elements.65D The application of ammoniumhydrogen sulphate fusion to spectrographic analysis, with volatilisation ofthe reagent, is discussed.44 A number of procedures have been de-scribed 651-653 for dealing with organic matter for spectrographic determin-ation of trace metals.Flame photometry. A detailed review has been published of the uses offlame photometry in metallurgical analysis; 654 it is pointed out that applic-ations of the method are not so widespread as its utility warrants, particularlyin production and control laboratories.The effect of organic solvents, oftenin. conjunction with extraction techniques, in enhancing sensitivity in flamephotometry, has received considerable investigation and application. Toexplain the effect Robinson 655 advances an alternative postulate to that ofincreased flame temperature. The effects due to addition of n-butanol 656and a number of solvents 657 are studied and discussed. Application hasbeen made to the detection of very small quantities of cations.658Several studies have been made of suppression of interferences in flamephotometry.EDTA has been used to avoid anion interference in thedetermination of a number of metals.659 Lanthanum chloride preventsinterference from aluminium, phosphate, and silicate in determining calciumin soils.660 The mechanism of interference has been studied in binary6.16 V. A. Korneev, Zhur. analit. Khim., 1960, 15, 170.647 V. A. Fassel and L. L. Altpeter, Spectrochim. Acta, 1960, 16, 443.618 G. H. Morrison, R. L. Rupp, and G. L. Klecak, Analyt. Chem., 1960, 32, 933.649 R. Geyer, K. Doerffel, and H. Kirst, 2. analyt. Chem., 1960, 172, 326.650 L. Pszonicki, Chem. Analit., 1960, 5, 139.651 S. I. Peizulaev, L. K. Popova, and R. L. Slyusareva, Zavodskaya Lab., 1960,652 W. J. Pienaar, S. African J. Agric. Sci., 1960, 3, 57.6.53 S. T. Bass and J.Connor, J. Assoc. OBc. Agric. Chemists, 1960, 43, 113.654 J - A. Dean, Analyst, 1960, 85, 621.655 J . W. Robinson, Analyt. Chim. Acta, 1960, 23, 479.656 K. Konopicky and W. Schmidt, Z. analyt. Chem.. 1960, 173, 358.657 R. Avni and C. T. J . Alkemade, Mikrochim. Acta, 1960, 460.658 D. Exley, Photoelect. Spectr. Group Bull., 1959, 322.659 A. C. West and W. D. Cooke, Araalyl. Chem., 1960, 32, 1471.660 C. H. Williams, Analyt. Chim. Acta, 1960, 22, 163.26, 552CARTWRIGHT AND WILSON : SPECTROSCOPIC ANALYSIS. 455mixtures of alkali metals with respect to method of atomisation and positionin the flame.661 Many other reports have been made of decreased inter-ferences in determinations of alkali metals and alkaline-earth metals :8-hydroxyquinoline has been used ,662 and a citric acid-ammonium citratebuffer.663 The depressive effect of certain anions in determination ofcalcium is obviated completely by adding some cations, and partially byadding others.664 The determination of barium or of sulphate is made morereliable by dissolving the precipitated barium sulphate in the ammoniumsalt of EDTA.665 Determination may be made of a small amount of ametal in solution without extensive calibration, by adding known quantitiesof the metal to the solution and by logarithmic extrapolation of the curveobtained.666Simple fluorimetry, where a sample is irradiated by non-monochromatic ultraviolet light and the overall intensity of the emittedlight is measured, continues to have many uses, both for fluorescent organicmaterials and for metal complexes.The method bears something of thesame relation to fluorescence spectroscopy as does colorimetry (also used as acomprehensive term) to spectrophotometry, with perhaps the complicationthat correlation between different instruments in fluorescence work is evenmore beset with difficulties than it is in spectrophotometry. There has beena great need for an examination of these difficulties, and for a recommendedform for presentation of published data, and these have been provided byParker and Rees in a comprehensive article. They discuss the origin offluorescence spectra and the measurement of fluorescence excitation spectra,fluorescence emission spectra, and fluorescence quantum efficiencies.Sec-tions also deal with the choice of units, methods of expressing sensitivity,and precautions to be taken in making measurements. Results are given forsix substances which fluoresce in the visible region. The fluorimetric deter-mination of boron is described; in high-purity silicon the method has alimit of detection of about 0.03 p.p.m., in sea water it is suitable for smallsamples and is more reliable than conventional methods, in steels the limitof detection is about 1 p.p.m.Two new designs for recording spectrofluorimeters have been described,668most of the components of which are commercially available while the re-mainder may be readily made. The performance of the instruments hasbeen compared with that of a commercial model. A study has been madeof the application of fluorescence spectroscopy in the qualitative and quantit-ative analysis of aromatic compounds.669 The influence of alkyl groups,the introduction of nitrogen and oxygen into the ring, and changes in solventhave been investigated.FZuorimetry.6 ~ 1 Shouzow Fukushima, Mikrochim.Acta, 1960, 332.J. Debras-Guedon and I. A. Voinovitch, Chem. Analit., 1960, 5, 193.J. L. Kassner, V. M. Benson, and E. E. Creitz, Analyt. Chem., 1960, 32, 1151.J. I. Dinnin, Analyt. Chem., 1960, 32, 1475.OG5 D. C. Cullum and D. B. Thomas, Analyst, 1960, 85, 688.T. E. Beukelman and S. S. Lord, jun., AppZ. Spectroscopy, 1960, 14, 12.067 C. A. Parker and W. T. Rees, AnaZyst, 1960, 85, 587.J. W. Goldzieher, W. S. Bauld, L. L. Engel, and M.L. Givner, Canad. J. Biochem.B. L. van Duuren, AnaZyt. Chem., 1960, 32, 1436.Physiol., 1960, 38, 233456 ANALYTICAL CHEMISTRY.Fluorimetric methods have continued to find use in both inorganic andorganic analyses. The determination of beryllium by using the fluorescentmorin-beryllium complex has been described"* and the method has beenapplied to the determination of beryllium in bronze.671 The addition of thedisodium salt of EDTA permits the determination of beryllium in the pre-sence of excess of copper, nickel, cobalt, or magnesium and to a lesser extentiron or manganese. Accounts have been given of the determination ofselenium by measuring the fluorescence of irradiated solutions containing thecomplex of selenium and 3,3'-diaminobenzidine. The method has beenapplied to crops and soil 672 and to biological material.673 Traces of uraniumin zirconium and hafnium may be measured in terms of ~ .p . r n . ~ ' ~ Uraniumis extracted in ethyl acetate, the extract evaporated and fused with sodiumfluoride containing lithium fluoride, and the fluorescence measured. Amethod for the determination of small amounts of ozone 675 is based on theextinction of the luminescence of luminol and fluorescein, or the change incolour of silica gel saturated with fuchsin solution.X-Ray methods. The principles of X-ray emission and fluorescencespectroscopy have been reviewed, and methods of minimising and correctingthe effects of other elements present discu~sed.~7~ X-Ray diffraction patternsmay be intensified by using an electronic image converter, enabling a shortexposure time to be used in crystal-structureIn the determination of certain rare earths an improvement in accuracy,convenience, speed, and economy resulted from the use of a fused disctechniq~e.~'B Standard discs for cerium, lanthanum, praseodymium, andneodymium may be made by fusion with sodium borate and employed indaily calibration.Traces of vanadium, iron, and nickel in petroleum oils may be rapidlydetermined by X-ray emission methods.s79 A-correction has to be madewhen sulphur is present but the interference of other elements is negligible.Monochromatic X-ray absorption has been used for the determinationof thorium.680 Lead and uranium do not interfere but bismuth and stron-tium do, and thorium must be extracted with tri-n-butyl phosphate.Absorption Spectroscopy.-Absorption by solutions in the ultraviolet andvisible regions is considered first , followed by atomic absorption spectro-scopy, and then by infrared and longer wavelength absorption.The terms photometry and spectro-photometry, although applicable to any spectral region, nowadays refer toUltraviolet and visible absorption.870 J.Bril and E. Pruvot, Mikrochim. Acta, 1960, 577.671 2. Holzbecher and J. Pokorn?, Chem. Listy. 1960, 54, 470.872 J. H. Watkinson, Analyt. Chem., 1960, 32, 981.678 F. B. Cousins, AustraE. J . Ex+. Biol. Med. Sci., 1960, 38, 11.874 P. A. Vozzella, A. S. Powell, R. H. Gale, and J. E. Kelly, Analyt. Chem., 1960,675 E.A. Peregud and E. M. Stepanenko, Zhzlr. analit. Khim., 1960,15, 96.876 A. Hans, Ind. chim. belge, 1960, 25, 353.877 R. E. Thun. 1. Tohnson, B. H. Krause, and E. A. Meredith, Analyt. Chem.,32, 1430.- " I 1960, 32, 939.878 D. R. Maneval and H. L. Lovell, Analyt. Chem., 1960, 32, 1289.679 Chia-Chen Chu Kang, E. W. Keel, and E. Solomon, Analyt. Chem., 1960,32, 221.680 J. H. Stewart, jun., Analyt. Chem., 1960, 32, 1090CARTWRIGHT AND WILSON : SPECTROSCOPIC ANALYSIS. 457measurements of absorption of ultraviolet and visible radiation, and theirapplications provide an enormous volume of published work.Improvements in apparatus include thermostatic devices 681*682 and amicrolitre adaptor.683 The measurement of absorption 88Q and of reflect-ance 685 by dense light-scattering samples is described.Further progresshas been made on continuous spectrophotometric monitoring of solutions,and on automatic measurements on large batches of samples.Methods for determining molar extinction coefficients of metal dithizon-ates have been reviewed, and a new and simple procedure, which should beof wide application, has been devised.686 The term differential spectro-photometry continues to be applied to two quite different types of deter-mination: that where one component is determined as a difference betweenthe sum of two and the other, as with nitrite and nitrate,687 or hydroxyl-amine and P-aspartyl hydroxamate; 688 and that where the reference is asolution of known concentration of the component being determined, as inapplication to various Determination of components in amixture has been made by utilising shifts in the peak wavelengths inducedby changes in pH.691 Measurements in non-aqueous solution of absorptiondue to nitro-derivatives permit characterisation and determination of anumber of organic functionalThere have been many hundreds of applications of spectrophotometry todetermination of individual elements, often following directly on solventextraction, or of organic compounds, many of them in the fields of bio-chemistry, food, and drugs.Only some of those with more general applic-ation or interest can be reported.Nine dyes have been investigated as colour and fluorescence reagents forgallium.693 The determination of phosphorus by the molybdenum-bluemethod has been reviewed,694 and the same method for arsenic has beeninvestigated and a report on it published by the Analytical Methods Com-mittee of the S.A.C.695 A critical survey has been made of the availablemethods for determining copper in water,69s and a number of derivatives ofThymol Blue have been tested as reagents for copper.697 A method has beenrecommended for the determination of trace quantities of silver in trade681 H.J . Martin and G. Gorin, Analyt. Chem., 1960, 32, 892.882 N. Macleod, Chem. and Ind., 1960, 342,6R3 D. Glick and L. J. Greenberg, Analyt. Chem., 1960, 32, 736.O84 W. L. Butler and K. H. Norris, Arch. Biochem. Biophys., 1960, 87, 31.M. E. Gibson, jun., D. A. Hoes, J. T. Chesnutt, and R.H. Heidner, Analyt. Chem.,686 H . Irving and R. S . Ramakrishna, Analyst, 1960, 85, 860.687 T. L. Lambert and F. Zitomer, AnaZyt. Chem., 1960, 32, 1684.J. Yashphe, Y. S. Halpern, and N. Grossowicz, Analyt. Chem., 1960, 32, 518.089 S. D. Ross and D. W. Wilson, Analyst, 1960, 85, 51, 276.890 T. M. Malyutina, B. M. Dobkina, and Y. A. Chernikhov, Zavodskaya Lab.,e91 Q. C. Belles and M. L. Littleman, Analyt. Chem., 1960, 32, 720.692 M. Pesez and J . Bartos, TaZanta, 1960, 5, 216.Bg3 I. M. Korenman, F. R. Sheyanova, and S. D. Kunshin, Zhwr. analit. Khim.,691 A. M. G. Macdonald, Ind. Chemist, 1960, 36, 88.695 Analyst, 1960, 85, 629.696 B. Tuck and E. M. Osborn, Analyst, 1960, 85, 105.1960, 32, 639.1960, 26, 259.1960, 15, 36.M. Koch, V.Svoboda, and J. Korbl, Taknta, 1960, 5, 141458 ANALYTICAL CHEMISTRY.effluents.6g8 A detailed study has been made of the characteristic constantsof 2,2',4'-trihydroxyazobenzene-5-sulphonic acid and of its use in the deter-mination of zirconium.6gg In a scheme for their separation and determin-ation, spectrophotometric methods have been recommended for each of theplatinum metals.226 The colorimetric determination of chloride has beenreviewed; 700 new reagents for nitrite are proposed,701 and serious interferenceby ammonium ions in the determination of nitrate by phenoldisulphonic acidis reported, and a simple remedy described.702The reaction of olefins with concentrated sulphuric acid has been used intheir spectrophotometric determination, singly and in some two-componentmixtures.703 Conjugated diolefins couple with 9-nitrobenzenediazoniumfluoroborate in 2-methoxyethanol-phosphoric acid to give strong absorptiondifferentiating clearly between isoprene-type and butadiene-type diolefin~.'~Vanadium oxinate in xylene or acetic acid gives colours with alcohols; '05there is no absorption peak, and the absorption is not linear with concen-tration, but it is reproducible.Low concentrations of primary and secondaryalcohols can be determined by formation of a red quinoidal ion, and secondaryalcohols by conversion into ketones and reaction with 2,4-dinitrophenyl-h y d r a ~ i n e . ~ ~ Aliphatic aldehydes give a colour with 2-hydrazinobenzo-thiazole suitable for spectrophotometric determination.ll5 The reactionbetween aldehydes and alcohols to form hemiacetals is very slow at 25" andalmost instantaneous at 100" ; simultaneous measurement of the aldehydepeak at these temperatures has been used in their determination.707A spectrophotometric study of the Schiff determination of sulphurdioxide 708 has led to a proposed mechanism.In the ferricyanide method forreducing sugars, oxalic acid can be used instead of a gum to peptise thePrussian blue.709Atomic abswption s$ectrosco$y. Although an absorption method, theproblems concerning atomic absorption spectroscopy are largely those ofemission spectroscopy and flame photometry. A comprehensive review hasappeared; 710 it deals with the history, theory, and instrumentation of themethod, and compares it with other analytical methods.There is a generalaccount of its applications and advantages.'ll A simple atomic absorptionspectrophotometer, suitable with slight modification also for flame photo-metry, has been described in detail.'12 In the metallurgical field the method698 T. B. Pierce, AnaZyst, 1960, 85, 166.899 M. H. Fletcher, AnaZyt. Chem., 1960, 32, 1822, 1827.700 A. M. G. Macdonald, Ind. Chemist, 1960, 36, 241.701 L. S. Bark, R. Catterall, 0. Meth-Cohn, and H. Suschitzky, Chem. and Ind.,702 F. B. Hora and P. J. Webber, Analyst, 1960, 85, 567.703 A. P. Altshuller, S. F. S1eva;and A. F. Wartburg, AnaZyt. Chem., 1960, 32, 946.704 A. P. Altshuller and I. R. Cohen, AnaZyt. Chem., 1960, 32, 1843.705 Senjiro Maruta and Fumio Iwama, J .Chem. SOC. Japan, Pure Chem. Sect., 1959,706 D. P. Johnson and F. E. Critchfield, AnaZyt. Chem., 1960, 32, 865; F. E. Critch-707 J. S. Forrester, AlaaZyt. Chem., 1960, 32, 1668.708 R. V. Nauman, P. W. West, and F. Tron, AnaZyt. Chem., 1960, 32, 1307.709 R. I. Mateles, Nature, 1960, 187, 241.710 D. J. David, Analyst, 1960, 85, 779.711 A. C. Menzies, AnaZyt. Chem., 1960, 32, 898.712 G. F. Box and A. Walsh, Specflochim. Ada, 1960, 18, 255.1960, 375.80, 1131.field and J. A. Hutchinson, ibid., p. 862CARTWRIGHT AND WILSON: THERMAL METHODS. 459has been applied to zinc in a number of alloys,713 and silver in copper alloys.714It has also had application to the determination of alkali and alkaline-earthmetals in soils 715 and in bloodInfrared absorption. The principal application continues to be to theelucidation of structure and binding in known pure compounds, rather thanto the detection and determination of unknowns.Although not reflected inpublished literature, however, the characterisation of unknowns by theirinfrared spectra is widely used, and quantitative work is considerably helpedby regular publication of condensed data in Analytical Chemistry. Ad-vances in techniques developed for structural investigations will generally beof application, sooner or later, in analysis.The preparation is described of micro-mulls giving resolution equal to orbetter than by the usual method.717 The preparation of capillary cells ofpotassium bromide, from which the sample may be recovered by dissolutionand extraction, is described.718 The use of an attenuating filter in the com-pensating beam improves the spectra of semi-opaque samples.719Errors in quantitative work because of failure to obey Beer's law can bedue to instrumental causes, but may be caused by solvent interaction ; theseare discussed and illu~trated.'~~ Infrared analysis has been applied to gas-chromatographic fractions and suitable measuring techniques have beendevised.721 A review has been made of its application to minerals.722 Mix-tures of diborane, dichloroborane, and trichloroborane have beenanalysed; 723 the effect of a number of gases on the determination of hydrogenfluoride has beenThe determination of benzaldehyde in presence of aromatic ketones, andof mixtures of nitrobenzaldehydes, has been carried out ,725 and octylphenoxy-ethanol additives to petroleum have been measured.726 Methods of samplepreparation are described which give spectra of barbiturates unaffected bythe initial crystalline state of the sample.727The applications of the longer-wavelengths absorption methods, micro-wave spectroscopy, nuclear magnetic resonance, and electron spin resonanceto analytical problems are still very restricted by specialisation of apparatusand techniques.They will be considered in a future Report.9. THERMAL METHODSSpecial consideration is given in this Report to thermal methods ofanalytical investigation, because of growing application and recent advances.718 J. A. F. Gidley and J. T.Jones, Analyst, 1960, 85, 249.714 B. M. Gatehouse and A. Walsh, Spactrochinz. Acta, 1960, 16, 602.715 D. J. David, Analyst, 1960, 85, 495.716 J. B. Willis, Sflectrochim. Acta, 1960, 16, 259, 273, 551.717 L. J. Lohr and R. J. Kaier, Analyt. Chem., 1960, 32, 301.718 E. D. Black, Analyt. Chem., 1960, 32, 735.719 J . Braunbeck, Angew. Chem., 1960, 72, 31.720 W. R. Ward, J. Appl. Chem., 1960, 10, 277.721 J . E. Stewart, R. 0. Brace, T. Johns, and W. F. Ulrich, Nature, 1960, 186, 628.722 W. M. Tuddenham and R. J. P. Lyon, Analyt. Chem., 1960.32, 1630.723 H. G. Nadeau and D. M. Oaks, jun., Analyt. Chem., 1960, 32, 1480.724 A. M. Deane, A.E.R.E. Report AERE-R 3261, 1960.725 R. M. Powers, J. L. Harper, and H. Tai, Analyt. Chem., 1960, 32, 1287.728 R.M. Shenvood and F. W. Chapman, jun., Analyt. Chem., 1960, 32, 1131.727 B. Cleverley, Analyst, 1960, 85, 582460 ANALYTICAL CHEMISTRY.Measurements of thermal stability have long been used in investigations ofexplosive materials, and more recently have had very general applications.An assessment of the thermal stability of a substance can provide usefulinformation on its suitability as a standard or as a weighing form in analysis.Thermal decomposition curves may be used as a method of identification,since they indicate phase changes as well as steps in decomposition character-istic of the material. In conjunction with other analytical methods thebehaviour of the substance on heating may be completely elucidated.The two basic methods of investigating thermal behayiour are thermo-gravimetric analysis, in which losses (or gains) in weight of the sample arerecorded, usually automatically, as it is gradually heated; and differentialt henna1 analysis, where exothermic or endothermic changes are similarlyrecorded with respect to an inert standard heated under the same conditions.There is a growing tendency to combine the two measurements to providefuller information, and there has been a welcome elucidation of reasons forthe inconsistencies, particularly in thermogravimetric work, often to befound in published data.Thermogravimetric Analysis-Newkirk 728 gives a detailed account ofthe errors, many of them not generally recognised, which may arise inthermogravimetry. He discusses the effects of air buoyancy and convectioncurrents, of thermal lag and reaction time, of heating rate, and of atmosphericchanges due to decomposition products of the sample, and illustrates themin a striking manner by experiment and from the literature. Garn andKessler investigate in further detail the effect of the atmosphere duringdecomposition, and develop a method 729 whereby the sample may be sub-jected to one atmosphere of its gaseous products at each stage of its reaction,and another 730 in which the decomposition products are withdrawn as rapidlyas possible from a thin layer of the sample. The applications of each methodare considered, and the differences in the results obtained are well illustratedand do much to explain lack of correlation in the past between differentworkers.A variation in the thermogravimetric method whereby the sample, in aninsulated block, is inserted into the already heated furnace, has been ap-plied 731 to a study of pyrolysis curves. Pyrolysis curves may be followed inanother apparatus 732 which is also suitable for collecting fractions of theproducts evolved.Thermogravimetric studies have been made of a number of sulphides toconfirm methods of drying and weighing,7= and in conjunction with infraredspectra, of many substances of use or potential use as standards in analysis.734The method has been applied to the determination, with greater generalsensitivity than by chemical analysis, of carbonates in soils.735 Further72* A. E. Newkirk, Analyt. Chem., 1960, 32, 1658.729 P. D. Garn and J. E. Kessler, Analyt. Chem., 1960, 32, 1563.73O P. D. Garn and J. E. Kessler, Analyt. Chem., 1960, 32, 1900.731 R. N. Rogers, S. K. Yasuda, and J. Zinn, Analyt. Chem., 1960, 32, 672.732 P. L. Waters, Analyt. Chem., 1960, 32, 862.733 I. K. Taimni and S. N. Tandon, Analyt. Ckim. Acta, 1960, 22, 34, 553.734 C. Duval and C. Wadier, Analyt. Chim. Acta, 1960, 23, 257, 541.735 J. R. Wright, I. Hoffman, and M. Schnitzer, J . Sci. Food Agric., 1960, 11, 163;I. Hoffman M. Schnitzer, and J. R. Wright, ibid., p. 167CARTWRIGHT AND WILSON: THERMAL METHODS. 461applications in conjunction with differential thermal analysis are mentionedbe1 ow.Differential Thermal Analysis.-An apparatus is described ?36 whichprovides means of controlling the pressure in the system and the compositionof gas flowing through the powdered sample, as well as the temperature, andits advantages and applications are discussed. The collection of evolvedgases, e.g., for mass spectrometry, simultaneously with registration on thethermogram has been described,737 and another apparatus permitting simul-taneous analysis of volatile products has been applied to the analysis ofmixtures of aluminium and iron oxides.7ss A simple arrangement allowsphysical changes in the sample to be observed at elevated temperatures.739Differential thermal analysis has been used in conjunction with zone melt-ingJ154 and for characterisation of epoxide resins.740Simultaneous thermogravimetric and differential thermal analyses may becarried out in a number of designs of apparatus. Markowitz and Boryta 741use a transducer to record weight differences and thermocouples for tem-perature differences. Reisman 742 describes a special furnace for the pur-pose, and gives a critical evaluation of constant-pressure phenomena con-cerned with dissociation of hydrates. An investigation by simultaneousapplication of both methods, termed a derivatographic study, has been madeof potassium hydrogen phthalate 743 to determine its safe drying range andmode of decomposition. Both methods have also been applied to studies ofthe thermal decomposition of uranyl carbonate and the sodium uranylcarbonate^,^^ quinolinium pho~phomolybdate,~~ EDTA and its deriv-a t i v e ~ , ~ ~ ~ a number of salts of guanidine and related andsome tetraphenylboron salts of oxine and four of its derivatives748Miscellaneous Thermal Methods.-Van Wijk and Smit 749 have carriedout a theoretical and experimental investigation into the melting curve of asample which has been gradually frozen, and have discussed the applicationof the expressions they derive to the determination of impurities by absoluteand by comparative heating-curve methods. Thermochemical titrationsprovide a rapid method of determining chloride in fused nitrate melts.750P. F. S. CARTWRIGHTD. W. WILSON.736 R. L. Stone, Analyt. C h m , 1960, 32, 1582.737 C. B. Murphy, J. A. Hill, and G. P. Schacher, Analyt. Chem., 1960, 32, 1374.738 W. Lodding and L. Hammell, Analyt. Chem., 1960, 32, 657.739 V. D. Hogan and S. Gordon, Analyt. Chem., 1960, 32, 573.740 H. C. Anderson, Analyt. Chem., 1960, 32, 1592.741 M. M. Markowitz and D. A. Boryta, Analyt. Chem., 1960, 32, 1588.742 A. Reisman, Analyt. Chem., 1960, 32, 1566.74a R. Belcher, L. Erdey, P. Paulik, and G. Liptay, Talanta, 1960, 5, 53.744 L. G. Stonhill, Analyt. Chim. Acta, 1960, 23, 423.745 W. W. Wendlandt and W. M. Hoffman, Analyt. Chem., 1960, 32, 1011.74t3 W. W. Wendlandt, Analyt. Chem., 1960, 32, 848.747 M. I. Fauth, Analyt. Chem., 1960, 32, 655.748 W. W. Wendlandt, J. H. van Tassel, and G. R. Horton, Analyt. Chim. Acta,749 H. F. van Wijk and W. M. Smit, Analyt. Chim. Ada, 1960, 23, 545.750 J. Jordan, J. Meier, E. J. Billingham, and J. Pendergrast, Analyt. Chem., 1960,1960, 23, 332.32, 651

ISSN:0365-6217    

DOI:10.1039/AR9605700410

出版商:RSC    

年代:1960

数据来源: RSC

摘要:

CRYSTALLOGRAPHY1. GENERALTHIS biennial Report covers the years 1959 and 1960. The difficulty inwriting such a report is to decide what to leave out. Guided by commonusage and the fact that this is a Chemical Society publication we have takenCrystallography to comprise only those studies of crystals which can bemade by the difraction of radiation, but excluding those concerned withdefects in crystals. The bulk of our report is therefore concerned withcrystal-structure analysis. When this limitation has been made, there arestill developments worthy of mention for which space cannot be found butwe hope that the more important ones have been covered.A number of conferences have been held under the auspices of theInternational Union of Crystallography. Symposia were held in Leningradin May 1959 in honour of E.S. Federov. The topics of these Symposia were“ Crystallographic Analysis and Crystal Chemistry ” and “ Electron Diffrac-tion.” 1 Three conferences on specialist topics were held in Stockholm inJune 1959. They dealt with “ The Precision Determination of LatticeParameters,” ‘‘ Counter Methods for Structure Analysis,” and ‘‘ TheX-Ray Wavelength Problem.” The fifth Congress of the InternationalUnion was held in Cambridge in August 1960, and was followed by symposiaon “ Thermal Motion in Crystals and Molecules ” and ‘‘ Lattice Defects andthe Mechanical Properties of Solids.” Approximately 560 papers werepresented; abstracts appeared in the December 1960 issue of Acta Crystallo-gvaphica, too late to be mentioned elsewhere in this Report.A brief accountof the first symposium has been published.2uHaving acquired the indexing habit, crystallographers have now begunto catalogue one another and the 2nd edition of the (‘ World Directory ofCrystallographers ” appeared in 1960. It contains the names of 3557 per-sons in 54 countries.Experimental Techniques.-Counter-diffractometers have come into in-creasing use in X-ray crystallography in the last decade. Although theyhave made possible some very accurate structure analyses, they have notdecreased the time spent on data-collecting, as they have been manuallyoperated. The trend is now towards automatic instruments which willrequire no more attention than a Weissenberg camera. Three alternativeanalogue devices by means of which counter and crystal motions may becoupled to explore reciprocal space along parallel lines have been de-scribed.3 A single-crystal diffractometer for neutron measurements whichwill automatically measure the intensities of all reflexions in a zone, taking itsinstructions from a punched paper tape prepared by a digital computer, is1 Reported in ZaF. vsesojuzn.mineral. Obshchest. S.S.S.R., 1959, 88, 615.2 Several papers appear in Acta Cryst., 1960, 13, 814, 818.20 C. E. Bacon, Nature, 1960, 188, 369.3 J . Ladell and I<. Lowitzsch, Acta Cr~fst., 1960, 13, 205.Titlesof papers are given, in French, in Bulletin Signale’tique, 1960, 21, 437COCHRAN: GENERAL. 463in ~peration.~ Equipment similar in principle is complete or nearing com-pletion in a number of X-ray laboratories.5 The linear diffractometer con-structed by Arndt and Phillips generates and applies its own settings forboth crystal and counter, given only the dimensions of the reciprocal latticeof the crystal under investigation.Two new diffractometers for the high-flux reactor DIDO, one for powder and one for single-crystal specimens,have been described.6Chandrasekhar has described a new experimental method of correctingfor extinction, which has the advantage of dealing with both primary andsecondary extinction.’ The same author has written a comprehensivereview of the subject.8Theory and Practice of Structure Analysis.-A conference on ‘ I ComputingMethods and the Phase Problem ” was held in Glasgow University in August1960, and brought out fully the considerable developments that have takenplace in both fields since the first such conference was held in 1950.It isintended to publish the conference proceedings in 1961. Developments inthe computer field and their great influence on the practice of structureanalysis must be held over for review in these Reports later.Karle and Hauptman have put forward a new statistical method9 inwhich relations between structure factors are obtained by keeping thestructure fixed and allowing the indices to vary, which contrasts with themethod used in their original monograph.1° Certain of the formuk can alsobe derived l1 by considering operations on the Patterson function. Thesimpler of the formulaz given in the monographlo have been successfullyused a number of times, most recently in determining the structure ofspurrite.12 These methods are obviously more powerful than seemedlikely to their critics (the Reporter was one of them), but their scope is stillthe subject of controversy.A geometrical interpretation of statisticalrelations between signs or phases of structure factors has been given.13Russian crystallographers in particular have made wide use of these signrelations in structure determination; a recent example l4 is provided bythe structure determinations of herderite, datolite, and gadolinite. Vain-stein l5 has derived new relations between structure factors which connectstructure factors belonging to parallel layers in the reciprocal lattice.“ Patterson-superposition ” methods have been the subject of a book andof two review articles.16 The topic of how best to determine a crystalstructure, given a partial knowledge of that structure, has attractedE.Prince and S. C. Abrahams, Bev. Sci. Instr., 1959, 30, 581.International Union of Crystallography Conference, Stockholm, 1959.G. E. Bacon and R. F. Dyer, J . Sci. Instr., 1959, 36, 419.7 S. Chandrasekhar, Acta Cryst., 1960, 13, 588.S. Chandrasekhar, Adv. Phys., 1960, 9, 363.@ J. Karle and H. Hauptman, Acta Cryst., 1959, 12, 404.lo H. Hauptman and J. Karle, “ Solution of the Phase Problem.symmetric Crystal,” New York, 1953 : Polycrystal Book Service.11 P. Vaughan, Acta Cryst., 1958, 11, 111; W.Cochran, ibid., 1958, 11, 579.l2 H. Hauptman, I. L. Karle, and J. Karle, Acta Cryst., 1960, 13, 451.13 Y. Kainuma and W. N. Lipscomb, 2. Krist., 1960, 113, 44.l4 P. V. Pavlov and N. V. Belov, Krystallografiya, 1959, 4, 324.l5 B. K. Vainstein, Krystallografiya, 1959, 4, 3.l6 M. J. Buerger, “ Vector Space,” J. Wiley & Sons, New York, 1959; V. I. Sinionov,h’ryslallograjiya, 1959,4, 302; C. A. Beevers and H. W. Ehrlich, 2. Krist., 1959, 112, 414.I. The Centro464 CRYSTALLOGRAPHY.considerable attention,17 largely because of developments in protein crystallo-graphy (see also a later section). Some improvements in the method ofgeneralised projections have been described.18 An improved method fordetermining the relative positions of molecules in the unit cell of a crystalwhen their shape and orientation are knownI9 has been used in a directdetermination of a structure (5-methoxy-2-nitrosophenol) by optical-transform methods.20Accurate Structure Analysis, etc.-A systematic.investigation of theelectron distributions in elements and simple compounds has been continued-005 - 0 0 5-005 -005\ tom0 \ ,---------- +002 ,/ \IFIG. 1.' 1 1 3with studies of diamond and of silicon.21 In order to avoid primary extinc-tion, measurements for silicon were made on powdered material with aparticle size of about 5 p, and in independent measurements on diamond 22the particle size was only 0-1 p. Sections and projections of the electrondensity show clearly the effects of the bonding electrons (see Fig.1). In the17 G. N. Ramachandran and S. Raman, Ada Cryst., 1959, 18, 957; G. A. Sim, ibid.,1960, 13, 511.18 M. G. Rossman and H. M. M. Shearer, Ada Cryst., 1958, 11, 829.19 C. A. Taylor and K. A. Morley, Actu Cryst., 1969, 12, 101.20 M. M. Crowder, K. A. Morley, and C. A. Taylor, Acta Cryst., 1959, 12, 108.21 S. Gottlicher, R. Kuphal, G. Nagorsen, and E. Wolfel, 2. phys. Chew. (Frunkfwt),22 R. Brill and H. Zandy, Nature, 1959,183, 1387; R. Brill, Acta Cryst., 1960, 18, 275.1959, 21, 133; S. Gottlicher and E. WolfeL 2. Electrochem., 1959, 63, 891COCHRAN : GENERAL. 465section (xxz) the difference between the measured density and that calculatedfor isolated atoms rises to a maximum, in the centre of the bond, of 0.51 e/A3in diamond and about 0.25 e/A3 in silicon.The figure for diamond is ratherhigher than was obtained in earlier measurements on organic compounds, butthe difference is to be expected in view of the very different temperaturefactors. Other measurements on diamond 22 gave results which have beeninterpreted in terms of the calculation of electron distribution made manyyears ago by Ewald and Hod. Careful measurements 23 on single crystalsof V,Al,, have shown no evidence of electron transfer from aluminium tovanadium d-levels on the scale required by Raynor's theory. In basicberyllium acetate 24 difference densities of up to 0.3 e/A3 were found in CCand CO bonds. I t was concluded that these are bonding effects, and cannotbe accounted for by errors of measurement or anharmonic oscillations.Thedifference electron density in 1,2:8,9-dibenzacridine 25 shows a deficit at thecentres of the rings, and the thirteen hydrogen atoms show up clearly inpositions which give d(C-H) = 1.08A. In the crystalline paraffins CiBH3,and C,,H,, the average value of d(C-H) determined by electron diffraction 26is 1.13 & 0.01 A. The electron distribution in NH,HF, has been deter-mined2' with a standard deviation of about 0.1 e/A3. The distribution inthe hydrogens of the ammonium ion is very similar to that in isolated atoms,no doubt as a result of near-cancellation of a number of effects. The peakdensity in the centrally-situated hydrogen of the (FHF)- ion is relativelylow, but the number of electrons within a sphere of radius 1.1 A approachesthe usual value.A neutron-diff raction study 28 of potassium hydrogen bisphenylacetateat 120" K has led to the fairly definite conclusion that in this compound theacidic hydrogen is Symmetrically situated between two oxygen atoms.Apreliminary study29 of sodium hydrogen diacetate shows that here ahydrogen atom is probably symmetrically situated in a bond for whichd(0-0) = 2-43 3 0.01 A. A useful survey of hydrogen-bond lengths andangles observed in crystals, with numerous references, has been made byFuller,3* and brings up to date the well-known review by Donohue.31 Recentindependent refinements 32 of data on naphthalene and anthracene givebond lengths in good agreement with one another, and agreement to within0.01 A with both molecular-orbital and Pauling-type calculations.It is in-teresting that better results were obtained for anthracene from measurementsof about 250 reflexions made by using a proportional counter than fromnearly 700 reflexions which were measured photographically. Cruickshank 33has discussed the conditions under which bond lengths can be considered2s A. E. Ray and J. F. Smith, Acta Cryst., 1960, 13, 876.z4 A. Tulinsky and C. R. Worthington, Acta Cryst., 1959, 12, 626; A. Tulinsky,e5 R. Mason, Proc. Roy. Soc., 1960, A , 2458, 302.26 B. K. Vainstein and A. N. Lobacher, Doklady Akad. Nauk, S.S.S.R., 1958,120, 523.27 T. R. R. McDonald, Acta Cryst., 1960, 13, 113.28 G. E. Bacon and N. A. Curry, Acta Cryst., 1960, 13, 717.zB J. C. Speakman, Proc.Chem. Soc., 1959, 316.30 W. Fuller, J. Phys. Chem., 1959, 63, 1705.3 l J. Donohue, J. Phys. Chem., 1952, 56, 502.32 D. W. J. Cruickshank and R. A. Sparks, Proc. Boy. Soc., 1960, A , 268, 270.33 D. W. J. Cruickshank, Acta Cr3~st., 1960, 13, 774.ibid., 1959, 12, 634466 CRYSTALLOGRAPHY.to be definitely established to within 0.01 8; in certain circumstancesthey are practically unattainable. New X-ray measurements of the atomicscattering factors of iron and of copper have been reported.= Thef-curvesare found to agree with those for the free atoms to within &l-0 electron,even at low scattering angles. The result for iron is to be contrasted withthat of Weiss and DeMarc0,3~ who concluded that in the crystal each ironatom has effectively only 2.3 3d electrons, as compared with 6 for the freeatom.New calculations of atomic scattering factors have been made fromHartree and Hartree-Fock wave functions.36 The effect of non-sphericalcharge distribution on X-ray and neutron scattering factors has been cal-culated 37 for d and f electrons in crystalline fields of cubic, hexagonal, andtetrahedral symmetries.Symmetry.-The use of space-group theory in considering the allowabletransitions at a ferromagnetic or ferroelectric transition has been described.=Most of the papers appearing on the subject of symmetry have in fact dealtwith antisymmetry ! The practical usefulness in structural crystallographyof the concept of an operation of antisymmetry, by means of which a func-tion may for example be reflected with simultaneous change of sign, becameapparent in connection with generalised projections of a crystal structure.The concepts plus-and-minus may equally well be replaced by up-and-down,black-and-white, or even top-and-bottom. There are for example 80 two-dimensional plane groups when both sides of the plane can be utilised inconstructing a pattern of unlimited extent.Of these, 17 use only one sideof the plane ( ‘ r uncoloured”), 17 have the same pattern on both sides(“ grey ”), and 46 have related patterns on both sides ( r 4 black-and-white ”).The notation that should be used to describe them has been the subject ofseveral ~apers.3~ These groups can also be used to describe the relation ofsymmetry to structure on twinning.40 The extension of antisymmetry spacegroups to three dimensions was made by Zamorzaev, and by Belov et al.; 41their number is 1651, made up of 230 uncoloured, 230 grey, and 1191 black-and-white.This work has been the subject of reviews in English, French,and German.42 The use of black-and-white space groups to describe thestructure of magnetic materials was possibly first suggested by MacKay,42and has now been the subject of a number of papers.& Donnay el al.34 B. W. Batterman, Phys. Rev., 1959, 115, 81.35 R. J. Weiss and J. J. DeMarco, Rev. Mod. Phys., 1958, 30, 59.36 A. J. Freeman, Acta Cryst., 1959, 12, 261; A. L. Veenendaal, C. H. MacGillavry,B. Stam, M. L. Potters, and M. J. H. Romgens, ibid., 1959, 12, 242.37 R. J.Weiss and A. J. Freeman, J . Phys. Chew. Solids, 1959, 10, 147.38 L. A. Shuvalov, Krystallogrufya, 1959, 4, 399; A. S. Sonin and I. S. ZheIudev,ibid., p. 487.39 W. T. Holser, 2. Krist., 1958, 110, 266; K. Dornberger-Schiff, Acta Cryst., 1959,12, 173; N. V. Belov, Krystallografiya, 1959, 4, 775.40 W. T. Holser, 2. Krist., 1958, 110, 249; K. Dornberger-Schiff, Acta Cryst., 1959,12, 246.41 A. M. Zamorzaev, 1953, Thesis, Leningrad; N. V. Belov, N. N. Neronova, andT. S. Smirnova, Kyystallogyajiya, 1957, 2, 315.42 A. L. MacKay, Acta Cryst., 1957,10, 543; Y . LeCorre, Bull. Soc. frang. Min. Crist.,1958, 81, 120; W. Nowacki, Fortschr. Min., 1960, 38, 96.43 G. Donnay, L. M. Corliss, J. D. H. Donnay, N. Elliott, and J. M. Hastings, Phys.Rev., 1958, 112, 1917; Y .LeCorre, J . Phys. Radium, 1958, 19, 750; N. N. Neronovaand N. V. Belov, Kvystullograj~~u, 1959, 4, 807COCHRAN : GENERAL. 467propose a systematic procedure for magnetic-structure determination whichtakes into account restrictions imposed on spin direction by space-grouptheory. However, it is now known that structures exist (e.g., MnAu,")in which the spins form a spiral whose period is incommensurate with thelattice periodicity; it is not clear whether these can be accommodated bythe theory. The number of point groups when antisymmetry operations areincluded is 122. These include the $8 black-and-white groups of Shubni-k0v.45 Tagver and Zaitsev 46 consider the antisymmetry operators as theproduct of a spatial operation by a reversal of time (which reverses a currentflow and changes the direction of a magnetic moment).This view has beencriticised by Sh~bnikov.~' (Mr. S. Pawley drew the Reporter's attention tomany of the papers mentioned in this section.)Structures of Magnetic Materials.-Thermal neutrons interact not onlywith the nuclei of atoms, but also with electrons whose magnetic moment isuncompensated. Apart from their importance for the theory of magnetism,neutron-diffraction studies of magnetic materials may eventually throwlight on problems of chemical bonding. The structure of Fe,N may bedescribed as an expanded y-Fe structure, with N in the body centre of theunit cell. Ferromagnetically aligned moments of 3pB and 211, are foundfor corner and face-centre Fe's respectively.& The difference of moments isprobably due to bonding interactions between N and the Fe's in face-centrepositions.FeBr,, CoBr,, FeCl,, and CoC1, have hexagonal structures withlayers of metal atoms separated by two layers of halogens.49 At low tem-peratures there is an antiferromagnetic transition to a structure in whichatomic moments within a layer form a ferromagnetic sheet, with antiparallelmoments in adjacent layers. In the iron compounds the moments areparallel to the hexagonal axis, in the cobalt compounds they are perpendi-cular to it. Symmetry considerations proved valuable in determining themagnetic structure of CuFeS,, which is antiferromagnetic at room temper-ature.= The two Fe tetrahedrally bonded to a common S have antiparallelmoments of 3-85 pB directed along a crystallographic axis.The momentof Cu is 0 & 0-2pB. The magnetic structure of MnAu, is particularly in-terestinga All magnetic moments in any plane perpendicular to the four-fold axis are parallel and in the plane, while the moments of atoms in neigh-bouring planes are rotated through 1 0 2 O , relatively. MnAu, is thus anexample of a helical antiferromagnetic structure. Neutron-diffractionresultsM confirm that in FeTiO, layers of Fe alternate with layers of Tialong the [lll] direction of the rhombohedral cell, and give more accuratepositional parameters for the oxygens. Data below the Nee1 temperaturesuggest a spin structure in which Fez+ moments are ferromagnetically44 A. Herpin, P. Meriel, and J.Villain, Compt. rend., 1959, 249, 1334.45 A. V. Shubnikov, " Symmetry and Antisymmetry of Finite Figures," 1951,46 B. A. Tagver and V. M. Zaitsev, J . Ex$. Theor. Phys. U.S.S.R., 1956, 30, 564,47 A. V. Shubnikov, Krystallofiya, 1960, 5, 328.4 x B. C. Frazer, Phys. Rev., 1958, 112, 751.4 9 M. K. Wilkinson, J. W. Cable, E. 0. Wollan, and W. C. Koehler, Phys. Rev.,50 G. Shirane, S. J. Pickart, R. Nathans, and Y . Ishikawa, J . Phys. Chem. Solids,Moscow.1959, 113, 497.1950, 10, 35468 CRYSTALLOGRAPHY.coupled within a (111) sheet, and are perpendicular to it. Solid solutionsof FeTiO, and cc-Fe20,, which sometimes show ferromagnetism althoughboth components are antiferromagnetic, were also studied.Ferroe1ectrics.-The discovery of new ferroelectrics has continued at anincreasing rate, and a number of their crystal structures has been determined,particularly by R.Pepinsky's group. Tricycline sulphate 51 has spacegroup P2, in the ferroelectric phase. One of three glycines is a zwitterionwith NH,+ not in the molecular plane; the remaining two are planarglycinium ions. In a reversal of the spontaneous polarisation almost allatoms make small movements, but there is in particular a movement ofhydrogen atoms so that molecules change from one type to the other. Abovethe Curie point, space group P2,/m is attained by a statistical distributionof molecules about the mirror planes. In LiH,(SeO,), hydrogen bonds mustalso play an important role in the dielectric behavio~r.~~ Fairly shortO-H - 0 bonds run nearly perpendicular to the polar direction, as intriglycine sulphate and in potassium dihydrogen phosphate.To improveour understanding of a ferroelectric transition we need to know not only theatomic displacements but also the directions of these displacements withrespect to the spontaneous polarisation. ' The absolute configuration ofmolecules can be determined by making use of the anomalous dispersion ofX-rays.53 Essentially the same method has now been applied= to showthat in tetragonal BaTiO, the displacement of Ti is in the direction of theelectric field. This was to be expected, but the confirmation is valuable.The structure of guanidinium gallium sulphate hexahydrate, which is iso-morphous with the ferroelectric [C(NH2),]Al(S0,)2,6H,0 has been deter-mined.55 The result does not agree with a trial structure put forward inde-pendently,56 and it seems probable that the latter is in~orrect.~' A deter-mination of the hydrogen positions in this substance using nuclear magneticresonance techniques 58 is therefore also suspect.Thiourea has been shownto be ferroelectric in two phases, below 169" K and between 176" and 180" K.The crystal structure has been determined in detail 59 at 120" K, in the lowerferroelectric region. The transition to a ferroelectric form is accomplishedby small rotations of molecules such that two become tilted to the ferro-electric b axis in a different way from two others. The relation betweenstructure and ferroelectricity in (Pb, Ba) and (Ba, Sr) niobates has beendiscussed.60 An X-ray, dielectric, and optical study of ferroelectric leadmetatantalate has been reported.61 This material resembles PbNb,06 62 in51 S.Hoshino, Y . Okaya, and R. Pepinsky, Phys. Rev., 1959, 115, 323.5 2 K. Vedam, Y . Okaya, and R. Pepinsky, Plzys. Rev., 1960, 119, 1252.5s Ann. Reports, 1951, 48, 361; 1956, 53, 384.54 Y. Okaya, R. Pepinsky, and F. Unterleitner, BUZZ. Amer. Phys. SOL, 1959, 4, 62.55 S. Geller and D. P. Booth, 2. Krist., 1959, 111, 117.56 L. A. Varfolomeeva, G. S. Zhdanov, and M. M. Umanskii, KrystuZZogru$yu, 1958,67 S. Geller, 2. Krist., 1960, 114, 148.68 I<. S. Aleksandrov, A. G. Lundin, and G. M. Mikhailov, Krystakkografiya, 1960,G. J. Goldsmith and J. G. White, J .Chem. Phys., 1959, 31, 1175.60 M. H. Francombe, Acta Cryst., 1960, 13, 131.61 E. C. Subbarao, G. Shirane, and F. Jona, Acta Cryst., 1960, 13, 226.62 M. H. Francombe and B. Lewis, Acta Cyst., 1958, 11, 696.3, 368.5COCHRAN: GENERAL. 469structure and dielectric properties, except that there is only one direction inthe former in which spontaneous polarisation can occur. A new method hasbeen developed 63 for determining possible space groups of pseudosymmetricstructures, i.e., those derived from a higher symmetry by small displace-ments. Application to NaNbO, has shown that at room temperature thespace group is most probably Pbma. Certain structures which are neitherferroelectric nor antiferroelectric are worthy of mention here. In BaTi,O, 64each Ti atom is in a distorted octahedron of oxygens, d(Ti-0) ranges from1-77 to 2-32 A, and each Ti is not at the centre of gravity of an octahedron.The displacements in two kinds of octahedra are 0.30 and 0-21 A severally,comparable with those found in ferroelectric BaTiO, and PbTiO,.Thestructure is not antiferroelectric according to the usual definition, since smallshifts of the atoms will not give a structure with higher symmetry. CsPbCl,has the cubic perovskite structure above 47" c ; but above, as well as belowthe transition, atoms are displaced from the ideal positions.65 The C1atoms appear to be statistically distributed over four positions, and Cs atomsover six. The structure is thus reminiscent of that put forward for BaTiO,,and now abandoned, in which Ti was distributed over a number of sites.Thermal Motion in Crystals.-This topic has attracted increasing attentionin recent years.In the course of an accurate structure analysis of a mole-cular crystal it is possible to deduce from the temperature factors (Debye-Waller factors) of individual atoms the elements of two symmetric tensorswhich specify the translational vibrations of each molecular centre of massand the angular oscillations about axes through the centre, provided thateach molecule moves as a rigid unit.66 A recent example is provided by theanalysis of the structure and atomic vibrations of 1,1,2,2-tetrafluorodi-phenyletha~~e.~~ It has been suggested 68 that it may be possible to gofurther than this, and find information about the principal distortingvibrations of molecules.In di-fi-xylylene the chief distorting vibrationsappear to be a " concertina '' movement and a relative twisting of the tworings.6g The compound 4,4'-dichlorodiphenyl sulphone has been the subjectof accurate analyses by both X-ray and neutron-diffraction techniq~es.~oThe two independent sets of thermal vibration parameters are in satisfactoryagreement, except that the motion of the sulphur atom appears moreanisotropic to neutrons than to X-rays. A neutron-diffraction study 71 hasshown that the nitrate groups in Ba(NO,), do not rotate. The relation be-tween thermal expansion and atomic vibrations in crystals has been thesubject of a review,72 as has thermal motion in hydrogen-bonded crystals.7563 H.D. Megaw and M. Wells, Acta Cryst., 1958, 11, 858.64 D. H. Templeton and C. H. Dauben, J . Chem. Phys., 1960, 32, 1515.65 C. K. Moller. Kgl. danske Videnskab. Selskab, Mat.-fys. Skrifter, 1959, 32, 1.66 D. W. J. Cruickshank, Acta Cryst., 1956, 9, 754.67 D. W. J. Cruickshank, G. A. Jeffrey, and S. C. Nyburg, 2. Krist., 1959,112, 385.68 K. Lonsdale and H. J. Milledge, Nature, 1959, 184, 1545.69 K. Lonsdale, H. J. Milledge, and K. V. Krisha Rao, Proc. Roy. SOL, 1960, A ,70 J: G. Sime and S. C. Abrahams, Acta Cryst., 1960, 13, 1; G. E. Bacon and N. A.71 G. Lutz, 2. Krist., 1960, 114, 233. '* K. Lonsdale, 2. Krist., 1959, 112, 188.73 J. M. Robertson, 2. Krist., 1959, 112, 68.255, 82.Curry, zbzd., 1960, 13, 10470 CRYSTALLOGRAPHY.The results mentioned so far have been obtained by measurement ofradiation which has been elastically scattered by a crystal.Inelastic scatter-ing of X-rays gives effects usually described as ‘‘ thermal diffuse scattering.”Hoppe 74 has reviewed the results of studies of organic molecules by X-raydiffuse scattering, and the possibility of using such measurements as an aidto structure analysis. Results of an extensive series of measurements ofthe thermal diffuse scattering by adipic acid, hexamine, and naphthalenehave been published.75 While the theory put forward to explain the resultshas defects, it is clearly established that the diffuse intensity is given to agood approximation bywhere the sum is over all molecules of one unit cell, Fi is the Fourier trans-form of the ith molecule, and exp(-2M) is the Debye-Waller factor.Inthe inelastic scattering of neutrons there is a measurable change of wave-length, which is not the case for X-rays. As a result it is possible to makea much more detailed study of the lattice dynamics of crystals by usingneutrons, and the relation between frequency and wave-number of thenormal modes of vibration of the crystal can be directly determined. Fromthese the force constants between any two atoms in the crystal can in prin-ciple be deduced. As yet only limited studies of simple crystals such asgermanium 76 and sodium iodide 77 have been reported; the results can bereasonably well accounted for in terms of a very simple force-constantmodel, provided the polarisability of the atoms is taken into a c c o ~ n t .~ ~ , ~ *Results for metals 79 as yet lack a satisfactory theoretical interpretation.Thermal motion in palladium hydride has been studied by both elastic andinelastic scattering of neutrons.80 The frequencies of the hydrogenvibrations in a number of metal hydrides 81 and in a series of phosphates 82have been determined by inelastic neutron scattering.Non-crystalline Materials-Bernal 83 has discussed the extension of theconcept of order in a three-dimensional lattice to cover the whole rangebetween a perfect crystal and a gas. A geometrical approach to the problemof the structure of liquids84 abandons the idea that a liquid resembles thecorresponding crystal, and suggests that the order of the molecular arrange-ment is of a simpler and different character, although the arrangement maybe similar in the first co-ordination zone.By slight modifications of icosa-hedra, irregular co-ordination polyhedra pack to give an irregular but dense74 W. Hoppe, 2. EleRtrochem., 1959, 63, 912.7R J. L. Amoros, M. L. Canut, and A. de Acha, 2. Krist., 1960, 114, 39.76 B. N. Brockhouse and P. K. Iyengar, Phys. Rev., 1958, 111, 747; A.. Ghose,H. Palevsky, D. J. Hughes, I. Pelah, and C. M. Eisenhauer, ibid., 1959, 113, 49.77 A. D. B. Woods, W. Cochran, and B. N. Brockhouse, Phys. Rev., 1960, 119, 982.78 W. Cochran, Proc. Roy. Soc., 1959, A , 253, 260.79 B. N. Brockhouse and A. T. Stewart, Rev. Mod. Phys., 1958, 30, 236.80 J. Bergsina and J.A. Goldkoop, Physica, 1960, 26, 744.81 W. L. Whitternore, A. W. McReynolds, and I. Pelah, Bull. Amer, Phys. SOC.,82 I. Pelah, I. Lefkowitz, W. Kley, and E. Tunkelo, Phys. Rev. Letters, 1959, 2, 94.83 J. D. Bernal, 2. Krist., 1959, 112, 4.84 J. D. Bernal, Nature, 1959, 183, 141; 1960, 68, 185.1959, 4, 246COCHKAN: GENERAL. 47 1structure in which each point has an average of 13.6 nearest neighbours. Itis suggested that there can be no intermediate phase between this denseirregular packing and crystallographic close-packing because irregular densepacking and pentagonal arrangements are necessarily connected. Theatomic distributions in liquid, plastic, and crystalline sulphur have beenstudied by computing radial distribution curves from X-ray data.85 Thenearest-neighbour distances and numbers remain at 2.07 and 2.0 respec-tively throughout, although other features change with temperature.De-tailed X-ray diffraction studies have been made of coals, coal extracts, andcarbonisation products.86 The results have been interpreted in terms of abasic structural model in which carbon atoms are arranged in small aromaticOH\layers linked by aliphatic material or by five-membered rings to form largebuckled sheets. The number of rings is thought to increase with rank. (SeeFig. 2.) In bituminous coals, heat treatment causes expulsion of volatilegroupings from peripheral regions of small clusters of two or three parallellayers of carbon atoms, and this is followed by coalescence of large layers toform larger sheets with distortions at the junctions.Changes in mean bondlength, in the number of layers associating to form a stack, and in thedistance between layers accompanying this process have been measured.The structures of boron oxide and alkali borate glasses have been the sub-ject of a review.87 The structural relationship of vitreous potassium borateto the crystalline modifications has been discussed.88 The crystal structuresof K20,5B203 and of Cs20,3B,03 have been determined,89 and are of interestin this connection. In the former the basic structural unit is a double85 C. W. Thompson and N. S. Gingrich, J. Chem. Phys., 1959, 31, 1598.86 L. Cartz and P. B. Hirsch, Phil. Trams., 1960, 252, 557; R. Diamond, ibid., 1960,87 J.Krogh-Moe, Phys. Chem. Glasses, 1960, 1, 26.J . Krogh-Moe, Arkiv Kevni, 1959, 14, 667.e8 J. Krogh-Moe, Arhier Kemi, 1959, 14, 439; 1960, 15, 889.252, 193472 CRYSTALLOGRAPHY.ring built up from one BO, tetrahedron and four planar BO, triangles,giving two six-membered rings in planes at 90°, linked by a B atom incommon. There are two interlocking separate borate frameworks, each inthe form of a helix, with two double rings to one turn of the helix. Theexistence of entangled networks may explain the reluctance of acid boratemelts to crystallise. In Cs20,3B,O, one out of every three boron atoms isfour-fold co-ordinated by oxygen, the other two being three-co-ordinated.The basic unit is a six-membered ring interlinked with identical rings in acontinuous three-dimensional network.w. c.2.INORGANIC STRUCTURESElements and Simple Compounds.-A new classification has been pro-posed for crystal structures of normal-valency compounds (covalent aswell as ionic phases) with simple atomic ratios. It is based on two para-meters which are supposed to measure the directional properties of bondsin a compound: (i) the average principal quantum number n of the valencyshell of the component atoms and (ii) the difference A between the electro-negativities of ion and cation. It is found that very many AiBj structures(i, j = 1, 2, 3) occur only in well-defined regions of a plot of n versus A.The classification should therefore be helpful in understanding and predictingthe structures of such compounds.Neutron-diffraction data for crystalline 4He has been subjected to aleast-squares analysis to yield improved lattice parameter^.^^ The frac-tional increase in interatomic distances in going from 4He to fi-3He, whichalso has a hexagonal close-packed structure, is 0.023, and is attributable tozero-point energy.An X-ray study of synthetic diamondsg2 has shownthat those prepared by G.E.C. always contain inclusions of nickel or of acompound rich in nickel. Those prepared by A.S.E.A. do not, but are lesswell crystallised. The structure of P-Hg, the form stable below 79" K, hasbeen determined 93 and discussed in terms of the relation with that of a-Hgand of Pauling's theory of resonating valency bonds in a metal. A neutron-diffraction investigation of cerium 94 has thrown some light on its magneticand specific heat anomalies.There are three crystallographic forms in thetemperature range 4-450" K, and the relative concentration of the phasesdepends both on temperature and on the previous history of the material.The existence of three modifications of boron is well established. Evidencefor the existence of others has been put forward, and one of these has beenfairly definitely identified as being tetragonal with approximately 192 atomsper ceL95 The structure of the tetragonal form with 50 atoms per cell isalready ~ I I O W ~ . ~ ~ The crystal structure of the rhombohedra1 form with90 E. Mooser and W. B. Pearson, Acda Cryst., 1959, 12, 1015.91 J. Donohue, Phys. Reo., 1959, 114, 1009.92 K.Lonsdale and H. J. Milledge, Mzn. Mug., 1959, 32, 185.93 M. Atoji, J. E. Schirber, and C . A. Swenson, J . Chem. Phys., 1959, 31, 1628.94 M. K. Wilkinson, H. R. Child, W. C . Koehler, and E. 0. Wollan, Bull. Amer. Phys.Soc., 1959, 4, 183.Acda Cryst., 1960, 13, 271.95 J. L. Hoard and A. E. Newkirk, J . Amer. Chem. SOL, 1960, 82, 70; C. P. Talley,96 J. L. Hoard, R. E. Hughes, and D. E. Sands, J. Amer. Ckern. SOC., 1968,80, 4607COCHRAN : INORGANIC STRUCTURES. 47312 atoms per cell has been fully described.97 It is composed of units ofnearly regular icosahedra in a slightly deformed cubic close packing. Thisrequires three-centre bonds, with two electrons shared by three boronatoms at the vertices of an equilateral triangle. A re-examination of thestructures of a- and P-nitrogen 98 has shown that a-N2 fits space group Pa3better than P2,3, which required a centrosymmetric molecule in a non-centrosymmetric space group ; 13-N, probably has space group PG,/mmc,with molecular centres again occupying centres of symmetry.At -35" c CCl, has a face-centred cubic structure with four moleculesper cell.The molecules are not rotating freely, but the data recorded fromrather poorly crystalline material did not enable a decision about the distri-bution of the chlorine atoms to be made.99In addition to ice-I (hexagonal) and ice-Ic (cubic), which are stable atatmospheric pressure, six ice polymorphs stable at pressures above 2000atmospheres are known. Ice-I11 is tetragonal (pseudo-cubic) with 12 mole-cules per cell.loO Each oxygen atom is surrounded by four others at 2-73to 2.90 A, in approximately tetrahedral co-ordination.Atoms OA formfour-fold spirals, with the spirals linked together by OB atoms each of whichforms bonds to the Ob in four separate spirals. Satisfactory hydrogenbonding and tetrahedral character of the water molecules is retained. Thearrangement of oxygen atoms is similar to that of silicon atoms in keatite(silica K), a high-pressure polymorph of SiO,.lol The crystal structure ofcoesite, another high-pressure form of silica, has also been determined.102Solid ammonia has been studied, both as NH, and as ND,. There are fourmolecules in a cubic unit cell; the nitrogen positions deviate only slightlyfrom face-centred cubic positions.Each molecule is involved in six hydrogenbonds of length about 3.4 A; the hydrogens appear to lie off the line of thebond. Ammonia monohydrate has the same structure at -95"c and at-160" c. Planar chains of water molecules are connected by hydrogenbonds of length 2-76 A. The chains are cross-linked by ammonia moleculesinto a three-dimensional network by short (2.78 A) bonds of type OH - . - Nand longer bonds (3.21-3-29 A) of type 0 - * HN.lo3 Hydrogen chloridemonohydrate has been shown lo* to contain H,O+ and C1-. The hydroxon-ium ions are flat pyramids, with each h drogen forming a bond to thenearest chlorine so that d(0-Cl) = 2-95 8: The hydrogen-bonded hydr-oxonium and chloride ions form trigonal puckered layers (see Fig.3).Rhodium monosilicide has the CsCl type of structure with a, = 2.963 A.105In KGe, which has space group PJ3n with a. = 12.80 A, Ge, tetrahedrahave their centres in special positions in the units cell, with K atoms arrangedbetween these.lo6 The compound BeSiN, has the wurtzite structure.10797 B. F. Decker and J. S. Kasper, Actu Cryst., 1959, 12, 503.98 L. H. Bolz, M. E. Boyd, F. A. Mauer, and H. S. Peiser, Acta Cryst., 1959,12, 247.99 B. Post, Acta Cryst., 1959, 12, 349.loo W. B. Kamb and S. K. Datta, Nature, 1960, 187, 140.101 J. Shropshire, P. P. Keat, and P. A. Vaughan, 2. Kvist., 1969, 112, 409.102 T. Zoltai and M. J. Buerger, 2. Krist., 1959, 111, 129.103 I. Olovsson and D. H. Templeton, Ada Cryst., 1959, 12, 827, 832.104 Y .K. Yoon and G. B. Carpenter, Acta Cryst., 1959, 12, 17.L. N. Finnie and A. W. Searcy, Acta Cryst., 1959, 12, 260.lo6 E. Bushmann, Naturwiss., 1960, 47, 82.lo' B. Brehler, Nuturmiss., 1959, 46, 106474 CRYSTALLOGRAPHY.The compounds LiAs and NaSb are isostructural.lm In the former, arsenicatoms form singly-bonded infinite parallel chains with d(As-As) = 2.45and 2.47 A. The Li atoms are in positions defined by a spiral of greaternFIG. 3.radius. Each atom has six neighbours of the other kind at corners of adeformed octahedron.Borides, Carbides.-Two forms of an aluminium boride have been investi-gated; cc-AlB,, is tetragonal (pseudocubic) and p-AlC,, is orthorhombic(pseudo-tetragonal) ; their detailed structures are unkn0wn.10~ The existenceof two phases with the composition Ni4B, has been established and theirstructures determined.ll* In the orthorhombic form, two-thirds of theboron atoms form infinite chains, while the remainder have no near boronneighbours.In the monoclinicform all the borons are connected in infinite chains. Manganese diboridehas been shown ll1 to have the AlB, structure, as have other transition-metalborides. The structure of Ru,B3 has been determined 112 and is similar tothat of C3Cr,. It provides another example of a boride with close similaritiesto the ‘‘ complicated” borides of Cr, Mn, and Fe. Other examples areCo3B and Ni3B which have the cementite (Fe3C) structure.l13 The pluton-ium borides, PUB,, with n = 1, 2, 4, and 6, have been identified; 114 theirstructures are isomorphous with those of NaCJ, AlB,, UB,, and CaB,, respec-tively.The preparation of crystals of silicon boride SiB, has been re-ported.l15This phase is structurally related to Cr3C,.108 D. T. Cromer, Acta Cryst., 1959, 12, 36, 41.109 G. A. Kohn and D. W. Eckart, Analyt. Chem., 1960, 32, 296.110 S. Rundquist, Acta Chem. Scarad., 1959, 13, 1193.112 B. Aronsson, Acta Cham. Scand., 1959, 13, 109.113 S. Rundquist, Acta Chem. Scand., 1958, 12, 658.114 B. J. McDonald and W. Stuart, Aclu Cryst., 1960, 13, 447.115 C. F. Cline, J . Electrochem. SOC., 1959, 106, 322; C. F. Cline and D. E. Sands,I. Binder, Acta Cryst., 1960, 13, 356.Nature, 1960, 185, 456COCHRAN: INORGANIC STRUCTURES. 475The structures of CaC, and of UC, have been determined by neutrondiffraction. In the former d(C-C) = 1-20 & 0.01 A, the triple-bond dist-ance, and in the latter the double-bond distance, 1.34 &- 0-01 A, is found.Other uranium carbides have been investigated by the same technique;UC has the NaCl structure and U,C, has a body-centred cubic structure withd(C-C) = 1.29, A.All have strong U-C bonding and weak U-U bonding.116An accurate redetermination 117 of the unit-cell dimension of ZrC has givend(Zr-C) = 2.349 A. The structure of molybdenum monocarbide has beendetermined .118Halides.-In B8Cl,, which is the fourth well-characterised boron chloride,boron atoms form a dodecahedron with triangular faces. One chlorine atomis attached to each boron at an average distance of 1-70 A.The shortestB-B distance is 1-78 A (see Fig. 4).ll9FIG. 4.Three forms of ZnC1, havea-form was determined and thatu tA molecule of B8C1,.been investigated; the structure of theof the p-form confirmed. ZnBr, and ZnI,have isomorphous tetragonal structures.f20 The crystal structure of VCl,appears, from powder photographs,121 to be of the CdI, type, with d(V-C1) =2.55 & 0.05 A; the structure of y-TiCl, has also been investigated.12,Niobium tetraiodide is orthorhombic, with eight formula units per cell.Infinite chains are formed by NbI, octahedra sharing edges. The niobiumatoms are not at the centres of octahedra but are shifted towards one anotherin pairs, the distance between atoms paired in this way being 3.2 A. TaI,is likely to have a similar structure.lS Antimony pentachloride has beenstudied at -35" c.The crystals are hexagonal with two molecules per cell,and the trigonal bipyramidal structure of the gaseous molecules is preserved.116 M. Atoji and R. C. Medrud, J . Chem. Phys., 1959, 31, 332; A. E. Austin, Acta117 C. P. Kempter and R. J. Fries, Analyt. Chem., 1960, 32, 570.118 A. E. Koval'skii and V. V. Kazarnikov, Krystallografya, 1959, 4, 923.119 R. A. Jacobson and W. N. Lipscomb, J . Chem. Phys., 1959, 31, 605H. R. Oswald and H. Jaggi, Helv. Chim. Acta, 1960, 43, 72; H. R. Oswald, ibid.,p. 77; B. Brehler, Angew. Chem., 1959, 71, 679.121 J. Villadsen, Acta Chem. Scand., 1959, 13, 2146.lZ2 G. Natta, P. Corradini, and G. Allegra, Atti Accad. naz. Lincei, Rend.Classe Sci.123 L. F. Dahl and D. L. Wampler, J . Amer. Chem. Soc., 1959, 81, 3150.Cryst., 1959, 12, 159.3s. mat. nut., 1959, 26, 155476 CRYSTALLOGRAPHY.Interatomic distances are d(Sb-C1) = 2-29 and 2.34 A, involving the chlorinesof the triangular base and those of the summits respectively.124 Crystalsof MoCl, and of NbC1, are isomorphous, with twelve formula units per cell.The structure is built up from dimers in which chlorine atoms form twooctahedra sharing a common edge, with a metal atom at the centre of eachoctahedron.lw A dimer of the same shape is found in crystals of NbOC1,.These h e r s form unusual linear chains of infinite extent, through Nb-O-Nbbonds .12,A new kind of distortion for octahedral CU(II) is found in the structure ofK2CuF,.In the distorted octahedron surrounding each copper, there aretwo fluorine ions at 1-96A and four a t 2.08k127 Crystals of CsPbI, areorthorhombic at room temperature. Distorted PbI, octahedra sharingiodine atoms form parallel chains, d(Pb-I) = 3.01-3.42 A. Above 306" cthere is a transformation to a distorted perovskite structure.128 The unit-cell dimensions of crystals of KMF,, with M = Mn, Fe, Co, Ni, and Cu,have been determined over a range of temperature from about 80" to 300" K.They exhibit a variety of distortions from the cubic form which most possessOxides, Hydroxides, Sulphides.-Evidence for the existence of B,O, witha structure probably closely related to that of tetragonal boron, has beenobtained from powder photographs.130 In the structure of p-Ga,O, twokinds of co-ordination, tetrahedral and octahedral, are found for Ga3+ withd(Ga-0) = 1.83 and 2-00 A severally (average values).The magneticaspects of the structure have been discussed.131 Crystals of Ti,O, aredimorphic, with a rapid reversible phase transition at 120" c. The structureof the low-temperature form may be described in terms of TiO, octahedrawhich share edges and corners to form an infinite three-dimensional frame-work. Some of the Ti-Ti distances are shorter than in the elernent.l3, Thestructure of V,O, is built up from VO, octahedra joined by sharing corners,edges, and faces. By means of this last connection ' I double octahedra "are formed; these are joined by edges to form infinite parallel rows.Thesame structure has been found in a phase TiCr,O,.lB Rhombohedra1V,O, has been investigated by neutron diffraction,l% and the oxygen co-ordinates have been accurately determined. The structure is very similarto that of cc-Fe203. It had been thought that below 168" K the substancehas an antiferromagnetic arrangement of spins; the neutron results do notsupport this conclusion but instead suggest a structural transition at thisat 300" K.12'124 S. M. Ohlberg, J . Amer. Chern. Soc., 1959, 81, 811.125 A. Zalkin and D. E. Sands, Acta Cryst., 1958, 11, 615; D. E. Sands and A.126 D. E. Sands, A. Zalkin, and R. E. Elson, A d a Cryst., 1959, 12, 21.127 K. Knox, J . Chem. Phys., 1959, 30, 991.128 C. K. M~rller, Kgl. danske Videnskab. Selskab, Mat.-fys. Medd., 1960, 32, 13.120 A.Okazaki, Y. Suemune, and T. Fuchikami, J . Phys. SOG. Japan, 1959, 14,180 R. A. Pasternak, Acta Cryst., 1959, 12, 612.131 S. Geller, J . Chem. Phys., 1960, 33, 676.182 S. Asbrink and A. Magneli, Acta Cryst., 1959, 12, 675.18s S. Asbrink, S. Friberg, A. Magneli, and G. Andersson, Ada Chetn. Scand., 1959,184 A. Paoletti and S. J. Pickert, J . Chem. Phys., 1960, 32, 308.Zalkin, ibid., 1959, 12, 723.1823.13, 603COCHRAN : INORGANIC STRUCTURES. 477temperature. The structure proposed some 24 years ago for baddeleyite(monoclinic 21-0,) has been shown to be in~0rrect.l~~ The seven shortestZr-0 distances in the co-ordination polyhedron around each Zr atom rangefrom 2.04 to 2.26 A; since the next is 3-77 A, the co-ordination number is 7.Another interesting feature of the structure is the alternation of fluorite-like layers containing oxygen atoms in tetrahedral co-ordination with layerswhich contain oxygen in triangular co-ordination.In the structures of dicalcium ferrite, Fe20,,2Ca0, and brownmillerite,Fe,,,AI,O3,2CaO , there are alternate layers of oxygen tetrahedra and octa-hedra, with Ca located in cavities between oxygens.For tetrahedral andoctahedral co-ordination respectively, d(Fe-0) is 1.86-1.88 and 1.96-1.97 A.136The crystal structures of a number of peroxides and peroxide hydrateshave been determined by N. G. Vannerberg.13' In the structure ofSr0,,8H20, chains of oxygen atoms and water molecules are maintained bystrong hydrogen bonds, and are joined in a three-dimensional structure bystrontium ions and weaker hydrogen bonds.Magnesium peroxide and zincperoxide (ZnO,) are isomorphous with pyrites. In the former, d(0-0) =1-50 & 0.02, d(Mg-0) = 2.08A, and in the latter d(0-0) = 1-48 0.03,d(2n-0) = 2-10 & 0.01 A. Cadmium peroxide has the same structure.138The method of preparation of solid phases of the system Ba0,-H,O-H202has been described, and the crystal structures of Ba0,,2H20,, ofBaO,,H20,,2H,O, and of Ba02,H20, have been determined.139 The lastcontains infinite helicoidal chains of peroxide groups linked by hydrogenbonds.An electron-diffraction study of crystals of CuC12,3Cu(OH), has shownthat the copper atoms lie in a plane in a pseudohexagonal array.On eitherside of this plane there are chlorine atoms and (OH) groups forming denselypacked layers in such a way that the copper atoms are octahedrally co-ordinated, with the distortion of the octahedron as expected for a com-pound of bivalent copper.14* The structure of the hexahydroxygermanate,FeGe(OH),, has an arrangement of Ge and Fe atoms roughly as in NaC1.Both are pseudo-octahedrally co-ordinated by oxygen atoms, at meandistances of 1.96 and 2.14 A respectively.la The hexahydroxystannatesM[Sn(OH),], with M = Fe, Mn, co, Mg, and Ca, are all cubic, with thecations surrounded by six oxygens in pseudo-octahedral co-ordination.142A determination of the deuterium positions in lanthanum deuteroxide byneutron diffraction has shown that there are no hydrogen bonds in thissubst a n ~ e .l ~ ~In the mineral LiAlPO,(OH,F) (edelamblygonite) each phosphorus atom135 J. D. McCuIlough and K. N. TruebIood, Acta Cryst., 1959, 12, 507.136 E. F. Bertaut, P. Blum, and A. Sagni&res, Acta Cryst., 1959, 12, 149.137 N. G. Vannerberg, ArRiv Kemi, 1959, 14, 17, 19, 199.138 C. W. W. Hoffman, R. C. Ropp, and R. W. Mooney, J . Amer. Chem. SOC., 1959,139 N. G. Vannerberg, Arkiv Kemi, 1959, 14, 125, 147.140 A. A. Voronova and B. K. Vainshtein, Krystallografiya, 1958, 3, 444.141 H. Strunz and M. Giglio, Naturwiss., 1959, 46, 489.142 H. Strunz and B. Contag, A d a Cryst., 1960, 13, 601.143 M. Atoji and D. E. Williams, J. Chem. Phys., 1959, 31, 329.81, 3830478 CRYSTALLOGRAPHY.is tetrahedrally co-ordinated by four oxygens, and each aluminium is octa-hedray co-ordinated by four oxygens and two (OH,F).The latter connectthe octahedra into parallel chains, which are linked through PO, groups.l44In the isomorphous series of minerals represented by MgAl,(POJ,(OH),(lazulite) similar units are found. The PO, groups tie the octahedralgroups laterally into sheets, and the sheets together into a three-dimensionala1-ray.1~5Europium sulphide, EuS, has the NaC1-type structure. Eu3S, has thesame structure as all the lanthanide sulphides of this composition, whileEu,S,(non-stocheiometric, Eu,S,.,) has the same structure as the corre-sponding gadolinium polysulphide. The oxysulphide Eu,02S has the samestructure as Ce,O,S. However, attempts to prepare Eu,S3 were not success-ful, although the tervalent character of the europium ion appears to be quitecertain in EU,O,S.~~ An X-ray investigation has shown the existence oftwo forms of MoS,, one hexagonal and one orthorhombic.The followinghave been identified in the niobium-sulphur system : monoclinic NbS,rhombohedra1 NbS,, and hexagonal NbS,, as well as non-stocheiometricphases1*' The high-temperature fonn u-V3S has a structure similar tothat of Ni,P. The low-temperature p-form has a structure related to thatof P-tung~ten.~,, In lorandite, TlAsS,, parallel chains of ASS, groups arelinked by irregularly co-ordinated thallium atoms.lBHydrates.-In CoC1,,6H20 two chlorine ions and four water moleculesform the usual octahedral arrangement around the central cobalt ion.Theother two water molecules are relatively free, and the groups are joined byhydrogen bonds.150 The crystal structure of FeC1,,4H20 contains twoformula units per cell. The distorted octahedra are linked by 0-H - C1bonds, and the water molecules have the usual tetrahedral environment.In the corresponding fluoride the discrete Fe(H,O),F, octahedra are ran-domly oriented over twelve possible sites for H,O and F. Each site has onthe average X = Q(F + 20), with d(Fe-X) = 1.96 A. The groups are againconnected by hydrogen bonds.151 A tetragonal modification of NiCl, ,4H,Ohas been found which contains ions in which nickel is octahedrally co-ordinated by water molecules in one case and by chlorine ions in the other,152with d(Ni-0) = 2-13 A.The structure of zirconium sulphate tetrahydrateconsists of layers of molecules held together by hydrogen bonds. Oxygenatoms form an antiprism about zirconium with d(2r-O) = 2.18 A, average.The SO, group exhibits a small departure from tetrahedral syrnmetry.lBThe perchlorate ions in perchloric acid monohydrate form nearly perfecttetrahedra with d(C1-0) = 1.42 A. The remaining oxygen is a hydroxonium144 W. H. Baur, Acta Cryst., 1959, 12, 988.145 M. L. Lindberg and C. L. Christ, Acta Cryst., 1959, 12, 695.146 L. Domange, J. Flahaut, and M. Guittard, Compt. rend., 1959, 249, 697.147 F. Jellinek, G. Brauer, and H. Mulle, Nature, 1960, 185, 376.148 B. Pedersen and F. Grplnwald, Acta Cryst., 1959, 12, 1022.149 A. Zemann and J. Zemann, Acta Cryst., 1959, 12, 1002.150 J.Mizunov, S. Ukei, and T. Sugawara, J . Phys. SOC. Japan, 1959, 14, 383.151 B. R. Penfold and J. A. Grigor, Acta Cryst., 1959, 12, 850; B. R. Penfold and152 E, V, Stroganov, I. I. Kozhina, S. N. Andreyeva, and A. B. Kolyadin, Vestnik153 J. Singer and D. T. Cromer, Acta Cryst., 1959, 12, 719.M. R. Taylor, ibid., 1960, 13, 953.Leningrad Univ., 1960, 4, 130COCHRAN : INORGANIC STRUCTURES. 479ion (although hydrogen atoms have not been directly located).lU Thestructure is similar to that of BaSO,.Anhydrous Salts, etc.-Anhydrous cupric nitrate, Cu(N0,) 2, has eightnear neighbours to each copper atom, two at 1-9 Theshorter bonds, which are presumably covalent, link alternate Cu and NO,into infinite chains.These parallel chains are arranged in pseudo-hexagonalarray and are linked sideways by the longer (ionic) bonds. The structureprovides no ready explanation of the volatility or colour of the compound.155Anhydrous ferrous sulphate is orthorhombic, and has a structure of theCrVO, type.156 In the orthorhombic modification of PbCrO,, chromium isat the centre of a regular tetrahedron of oxygens, with d(Cr-0) = 1.65 A.Each lead atom is surrounded by twelve oxygens at distances between 2.64and 3.57 A,157 The structure of KCr,O, contains CrO, octahedra and CrO,tetrahedra arranged in layers with shared corners, and the layers are heldtogether by potassium ions.158 Each manganese atom is at the centre ofa nearly regular tetrahedron of oxygens in Ba(MnO,),, and two of these aresymmetrically related to a barium atom.This structural unit is repeatedat the points of a diamond 1 a t t i ~ e . l ~ ~ Crystals of KV,O, and CoV,O, areisomorphous. They contain layers of fused VO, octahedra which are verydistorted, with the positive ions in interlayer positions.16* Almost regularpentagons of vanadium atoms are found in the structure of K3V5014. Thebonding of fourteen oxygens to these is similar to the arrangement found inV205. Each -hollow space resulting from the five-ring configuration isoccupied by a potassium atom roughly half-way between the layers, so thateach potassium has ten near neighbours.lel Each rhenium atom in KReO,is tetrahedrally co-ordinated, the value d(Re-0) of 1.77 suggesting con-siderable double-bond character.162 The oxygen atoms have not beendirectly located in the structure of W,O,(PO,),, but it has been deduced thatWO, octahedra are linked by PO, tetrahedra in a three-dimensional net-work.Every octahedron is linked to one octahedron and four tetrahedra,and every tetrahedron is linked to four 0~tahedra.l~~ In sodium tri-phosphate, Na,P,O,,, the triphosphate ions are situated on a two-fold axis.Certain sodium atoms have a distorted octahedral co-ordination, while theremainder are four-fold co-crdinated in an unusual way.164 The mineralfergusonite (Y, Yb)NbO, has been found to be isostructural with the scheelitegroup of minerals, and an X-ray study of synthetic rare-earth compoundsof the LnNbO, type has also been r e ~ 0 r t e d .l ~ ~Metal Complexes, etc.-There has been considerable interest in the15* F. S. Lee and G. B. Carpenter, J. Phys. Chem., 1959, 63, 279.lS7 G. Collotti, L. Conti, and M. Zocchi, Acta Cryst., 1959, 12, 416.ljQ A. Hardy, C. Piekarski, and P. Hagen-Muller, Compt. rend., 1959, 249, 2579.I6O S. Block, Nature, 1960, 186, 540.161 A. M. Bystrom and H. T. Evans, Acta Chern. Scand., 1959, 13, 377.J . C. Morron, Acta Cryst., 1960, 13, 443.163 P. Kierkegaard, Acta Chem. Scand., 1960, 14, 657.D. E. C. Corbridge, Acta Cryst., 1960, 13, 262.16% A. I. Komkov, KrystaZZografya, 1959, 4, 836; Doklady Akad. Nauk S.S.S.R.,and six at 2.5 A.S. C. Wallwork, Proc. Chem. Soc., 1959, 311.J. Coing-Boyat, Acta Cryst., 1959, 12, 939.K. Wilhelmi, Acta Chem.Scand., 1958, 12, 1965.1969, 126, 853480 CRYSTALLOGRAPHY.structures of glyoxime-metal complexes. Palladium dimethylglyoxime isisomorphous with the corresponding nickel compound, but the molecule issomewhat more symmetrical. The palladium atoms are directly above oneanother with a separation of 3.26A. The corresponding distance in theplatinum compound is 3.23 A. In the latter compound the distance 3.03 Abetween oxygens linked by a hydrogen bond is considerably greater thanin the nickel compound (2.40 A) or the copper compound (2.57-2-70 hi).lMCopper dimethylglyoxime has in fact a different structure.16' The twoorganic radicals bonded to copper do not lie in a plane, and as well as beingbound to four nitrogens, each copper is at 2.43 A from the oxygen of a neigh-bouring molecule, so that a dimer is formed (see Fig.5). Nickel ethyl-FIG. 5. A perspective of a pair of copper dirnethylglyoxirne molecules.methylglyoxime has a planar molecule, and the trans-configuration. Thereis no intermolecular Ni-Ni bond, and the length of the intramolecularhydrogen bond is reported to be 2-33 A.168The structures of the cobalt and copper complexes with dithiocyanato-dipyridine, Cu(NCS),,2Py, have been determined.169 Each copper is incontact with two nitrogens and two sulphurs of the NCS groups, and thenitrogen atoms of two pyridines complete the co-ordination. The NCSgroups form bridges between the metal atoms. In bisethylenethiourea-cadmium thiocyanate, cadmium is octahedrally co-ordinated by two sul-phur atoms attached to ethylenethiourea molecules and by two sulphursand two nitrogens in four different NCS groups.The octahedra are linkedin chains by these NCS groups which form bridges between cadmiumatoms.170 The four nitrogens of the amine and the two of the thiocyanate166 D. E. Williams, G. Wohlaner, and R. E. Rundle, J. Amer. Chem. SOC., 1959, 81,755; E. Frasson, C. Panattoni, and R. Zannetti, Acta Cryst., 1959, 12, 1027; C. Panat-toni, E. Frasson, and R. Zannetti, Gazzetta, 1969, 89, 2132.167 E. Frasson, R. Bardi, and S. Bezzi, Actu Cryst., 1959, 12, 201.168 E. Frasson and C . Panattoni, Act@ Cryst., 1960, 18, 893.169 M. A. Porai-Koshits and G. N. Tishchenko, Krystallografiya, 1969, 4, 239.170 L. Cavalca, M. Nardelli, and G.Fava, Aclu Cryst., 1960, 13, 125COCHRAN : INORGANIC STRUCTURES. 481groups form a distorted octahedron around nickel, with the thiocyanategroups in the cis-position, in the crys t a1 structure of 2,2’, 2”-t riamino t net hyl-aminenickel(11) dithi0~yanate.l~~ Since the rings N-C-C-N are not planar,the compound is asymmetric and can have two enantiomorphous forms.The structure of tram-dichlorobisethylenediaminecobalt(~~~) chloridecontains a slightly deformed octahedron, with four nitrogens in the sameplane as cobalt, but carbon atoms of the ethylenediamine bridge are out ofthis plane. Chlorine atoms complete the octahedral co-ordination.172 Intrisethylenediaminenickel(11) nitrate 173 two nitrate ions are packed oneabove the other to form a close packing with the complex ions [Ni en3]++,baFIG. 6.The [OOI] firojection of L-ddd-[Ni en,](N03),.as shown in Fig. 6. In the structure of Ni(NH,),(NO,),, nickel is co-ordin-ated to four NH, groups in a square, with NO, groups above and below,each having its plane parallel to a side of the square and with d(Ni-NH,) =2.07, d(Ni-NO,) = 2.23 a.174 Ruthenium is octahedrally co-ordinated byfour NH, groups in square array, with an oxygen and a nitrogen atom a t thesummits, in the structure of [Ru(NO) (OH) (NH,),]C1,.175Cadmium is octahedrally co-ordinated, and the biuret molecules areplane and in the trans-configuration, in bisbiuretcadmium chloride.176Cobalt is octahedrally co-ordinated by oxygen atoms in bisacetylacetone-171 S. E. Rasmussen, Acta CAem.Scand., 1959, 13, 2009.172 K. A. Becker, G. Grosse, and K. Plieth, 2. Krist., 1959, 112, 375.173 L. N. Swink and M. Atoji, Acta Cryst., 1960, 13, 639,174 M. A. Porai-Koshits and L. M. Dikareva, Krystallografiya, 1959, 4, 650.1 7 5 G. B. Bokii and N. A. Parpiev, Zhur. neorg. Khirn., 1959, 4, 2452.176 L. Cavalca, M. Nardelli, and G. Fava, Acta Cryst., 1960, 13, 594.REP.-VOL. LVII 482 CRYSTALLOGRAPHY.cobalt(I1) dihydrate, and the molecules are bound in layers by hydrogenb0nds.l" The nickel@) and copper(I1) complexes of bis-salicylaldimine areisomorphous. Plane molecules in the tram-configuration are packed ratheras in naphthalene crystals. The configuration around the metal atom isnot quite square.178 The glycinate complexes of zinc and of cadmium,M(NH2*CH2C0,),,H,0, are isomorphous, and the metal atoms are octa-liedrally co-~rdinated.~~~ The crystal structure of the cuprous chloride-azomethane complex, Cu,Cl,,C,H,N,, contains endless CuCl chains[d(Cu-Cl) = 2.35 A] which are joined in pairs by weaker CuCl bondsa'a[d(Cu-C1) = 2.65 A].The chains arc further linked through trans-azo-methane molccules by CuN bonds [for which d(Cu-N) = 1.99 A]. There isa (distorted) tetrahedral co-ordination around each copper.lsOThe structure of tricarbonylchromiumbenzene appears to favour thehypothesis of d2sp3 hybridisation of chromium in this interesting compound.All benzene carbon atoms are at the same distance, 2.25 0-05 A, fromchromium, and the carbon and oxygen of each C=O group are collinear withchromium with d(Cr-0) = 2.95 & 0.05 A.The plane of the oxygen atomsis parallel to the benzene plane. In the structure of biphenylbistricarbonyl-177 C. J. Bullen, Acta Cryst., 1959, 12, 703.178 H. J. Stewart and E. C. Lingafelter, A d a Cryst., 1959, 12, 842.179 B. W. Low, F. L. Hirshfeld, and F. M. Richards, J . Amer. Chem. Suc., 1959,180 I. D. Brown and J. D. Uunitz, Acta Cryst., 1960, 13, 28.81, 4412COCHRAN : INORGANIC STRUCTURES. 483chromium, two phenyl groups are coplanar with chromium and are in thetrans-configuration lS1 (see Fig. 7). In the ethylene complex, trans-[Pt(C,H,) (NHMe,)ClJ, ethylene is linked t o platinum by a symmetricalbond with two carbons equidistant from p1atinum.ls2 The arrangement ofatoms is shown in Fig.8.FIG. 8. Thc nzolectdar configuration, with iwzteratomic distances (in A) and angles.Addition Compounds.-The crystal structures of a number of transfercompounds having halogens as electron acceptors have been determined.The compounds [ (CH,),NH,Rr] 2Br, (dimethylammonium bromide-bromine)and [(CH,),NH,CL],I2 are isomorphous. They contain linear Br, andC112C1 chains, with the distance between central atoms a little longer than inthe free molecule. Each end halogen is bonded to three nitrogens withd(N-Br) = 3.05, 3.49, and 3.50 A. The shortest bond lies along one of thenitrogen's tetrahedral directions.lS5 In the compound (CH,),N,I, formedby iodine with trimethylamine, d(1-I) at 2.83 A is longer by 0.17 A than inthe free molecule. The nitrogen-halogen arrangement is linear, andd(N-I) = 2.27 A suggests a strong interaction.(CH,),N,ICl has also beeninvestigated, with rather similar results.lS6 Acetone and bromine form a1 : 1 addition in which there is a linear OBr,O chain, withd(Br-Br) = 2-28 A (close to the value for molecular bromine) and d(0-Br) =2.82 A. There are chains of alternating benzene and chlorine molecules inthe 1 : 1 addition compound which they form,ls8 with d(C1-C1) = 1.99 A,and the distance from C1 to the nearest benzene plane is 3.28 A. The crystalstructures of 1 : 1 molecular compounds between 1,4-dioxan and chlorineand 1,4-dioxan and sulphuric acid have also been determined.lsg The com-181 P. Corradini and G. Allegra, J . Amer. Chem. SOL, 1059, 81, 2271; 1960, 82, 2075.la2 P.R. H. Alderman, P. G. Owston, and J. M. Rowe, Acta Cryst., 1960, 13, 149.Ia3 D. R. Fitzwater and R. E. Rundle, 2. Krist., 1959, 112, 362.la4 E. A. Shugam and L. M. Shkolnikova, Usfiekhi Khim., 1959, 28, 889.lE5 K. 0. Strrmme, Acta Chem. Scand.. 1959, 13, 2089.la6 K. 0. Strrmme, Acta Chem. Scand., 1959, 13, 268; 0. Hassel and H. Hope,187 0. Hassel and K. 0. Strarmme, Acta Chem. Scand., 1959, 13, 275.la8 0. Hassel and K. 0. Strrmme, Acta Chem. Scand., 1959, 13, 1781.la9 0. Hassel and K. 0. Stramme, Ada Chem. Scand., 1959, 13, 1776; 0. Hasselibid., 1960, 14, 391.and C. R~mming, ibid., 1960, 14, 398484 CRYSTALLOGRAPHY.pounds C4H8S,,21, (1,4-dithian-di-iodine) and C4H,Se,,21, are isornorph~us.~~~In the latter, the molecules are centrosymmetric and d(Se-I) at 2-81 A is0.1 A longer than the expected value for axial ISeI bonding.The angleSeII is 176", near to the value for the I,- ion. Although these compoundsare isomorphous, the two molecules have very different orientations of the1-1 line to the six-membered ring. The oxychloride functions as a donormolecule in the compound SbCl,,POCl,. The co-ordination is octahedralaround antimony, with an oxygen from POCl, in the sixth corner. Theapproximately tetrahedral structure of POCl, is preserved, as is the case inthe structure of (TiCl,,POCl,),. In the latter the titanium co-ordination isoctahedral, and there are double chlorine bridges between the two titaniumatoms of the dimer.lglIntermetallic Compounds.-F.C. Frank and J. S. Kasper have pointedout that the structures of complex alloys, particularly of transition metals,can be considered as determined by the geometrical requirements for thepacking of spheres. A class of structure was discussed in which co-ordinationpolyhedra have only triangular faces. Four such polyhedra are prominentin actual structures. The general principles and properties deduced forthis class of alloy structure have been applied t o a classification of repre-sentative structures, mainly with regard to the nature of layers and how theystack.A number of new intermetallic compounds of beryllium have been identi-fied. Mo,Be is isomorphouswith Mo,Si. The compounds M,B,,, with M = Hf, Nb, Ti, Ta, Zr, are allisomorphous, as are MBe,, for M = Mo, Re, W.LaBe, and ZrBe,, havethe NaZn,, type of structure.lg3 The structure of Nb,Be, is the same asthat of U,Si,.lg4 The crystal structures of Nb,Be,,, NbBe,, and NbBe,have been completely determined.lg5 ZrBe, has the same structure asCaCu,. Interatomic distances are very accurately given since all atomsoccupy special positions of the space group P6/mmm.lg6The crystal structure of Zr,Al, conforms to the principle of sphere packingin alloy structures enunciated by Frank and Kasper. It is similar to thatof Hg,Na,, but not isomorphous. It is somewhat surprising to find that thestructure of Zr,Al, is isomorphous with that of Mn,Si,, which is typical ofthat formed by a transition element with Si, Sn, or Ge. The structure ofZrAl, is a Laves phase of the MgZn, type, while that of Zr4A13 has a closeresemblance to the o-phase structure of the transition e1e1nents.l~~ It isidentical with a structure postulated by Frank and Kasper.Many hypothetical structures have been listed.lg2In some cases their structure is not known.190 J.D. McCullough, S. Y . Chao, and D. E. Zuccaro, Acta Cryst., 1959, 12, 815;191 I. Lindqvist and C. I. Branden, Acta Cryst., 1959, 12, 642; C. I. Branden and192 F. C. Frank and J. S. Kasper, Acta Cryst., 1958, 11, 184; 12, 453.193 R. M. Paine and J. A. Carrabine, Acta Cryst., 1960, 13, 680.194 A. Zalkin, D. E. Sands, and 0. H. Krikorian, Acta Cryst., 1960, 13, 160,195 A. Zalkin, D. E. Sands, and 0. H. Krikorian, Acta Cryst., 1959, 12, 713; D.E.196 A. Zalkin, R. G. Bedford, and D. E. Sands, Acta Cryst., 1959, 12, 700.197 C. G. Wilson and F. J. Spooner, Acta Cryst., 1960, 13, 358; C. G. Wilson, D.Sams, and T. J. Renouf, ibid., 1959, 12, 947; C . G. Wilson, ibid., 1959, 12, 660; C. G.Wilson, D. K. Thomas, and F. J. Spooner, ibid., 1960, 13, 56.S. Y . Chao and J. D. McCullough, ibid., 1960, 13, 727.I. Lindqvist, Acfa Chem. Sand., 1960, 14, 726.Sands, A. Zalkin, and 0. H. Krikorian, ibid., p- 461COCHRAN : INORGANIC STRUCTURES. 485Truncated tetrahedra, icosahedra, and hexagonal prisms are all promi-nent as co-ordination polyhedra in the structure of Mg,CrzAll,.lgs Thephase B(Cr,Al) is isomorphous with a'(V,Al) and has the compositionCrA16.6. The chromium atoms are co-ordinated by nearly regular icosahedrawhich may interpenetrate or share corners or faces with other icosahedra.The Cr-A1 distances are in two groups, centred around 2.53 and 2.74Aseverally.Various features of the structure suggest that the short bondshave directional properties.lg9 These short bonds also occur in Mg3Cr,AlI8.The structure of VCO, is closely related to the ordered structure of the AuCu,type.200 Some eighteen compounds of the type M,X have been prepared,with X a rare earth or yttrium, and M = Co, Ni, or Cu. All have the CaCu,type of structure. The interatomic distances appear to indicate that ceriumhas a valency greater than three.201A new face-centred cubic form of nickel nitride, Ni,N, has been identifiedby electron diffraction.202The structure of K,Hg, may be regarded as derived from that of KHg,by replacing one-eighth of the mercury atoms by potassium, in a regularway.,N An X-ray study of the compounds Rb,Bi and Rb,Sb, using powderspecimens, has led to a complete structure determination.2M X-Rayphotographs of the compound Bi,Rh show only one structure between roomtemperature and 460" c, although allotropic forms have been reported.,05The structure of Cs,Bi has been determined.2mThe compound UPt, may be regarded as formed from UPt, by removingcertain planes of Pt atoms and making relative movements of the remainingplanes of atoms.207 The structure of PuNi is of the T1I type, in which eachatom has seven neighbours of opposite kind, and in addition each Ni has twoNi neighbours and Pu has eight Pu neighbours at a greater distance.Thestructure of PuNi, is derived by stacking single layers of the MNi, structure(CaCu, type) and double layers of the MNi, structure (Cu,Mg type) .,08Silicate and Borate Minerals-N. V. Belov has reviewed the crystalchemistry of certain silicates.209The crystal structure of proto-enstatite, one of the five forms of MgSiO,so far described, has been determined in outline from X-ray powder photo-graphs.210 The structure of rhodonite (Mn, Ca)SiO, is triclinic, with tenformula units per cell. SiO, tetrahedra form chains, the period of whichcontains five tetrahedra, along [OOl]. Layers of these chains alternate withlayers of cations in (110). The structure resembles that of P-wollastonite,198 S.Samson, Acta Cryst., 1958, 11, 851.lg9 M. J. Cooper, Acta Cryst., 1960, 13, 257; P. J. Brown, ibid., 1959, 12, 995.Zoo S. Saito, Acta Cryst., 1959, 12, 500.201 J. H. Wernick and S. Geller, Acta Cryst., 1959, 12, 662.202 N. Terao, Naturwiss., 1959, 46, 204.203 E. J. Duwell and N. C. Baenzinger, Acta Cryst., 1960, 13, 476.204 N. N. Zhuravlev, V. A. Smirnov, and T. A. Mingazin, Krystallogrufya, 1960,205 R. G. Ross and W. Hume-Rothery, J . Less Common Metals, 1959, 1, 304.206 N. N. Zhuravlev and V. A. Smirnov, Krystallografyu, 1959, 4, 534.207 B. A. Hatt and G. Williams, Acta Cryst., 1959, 12, 655.208 D. T. Cromer and R. B. Roof, Acta Cryst., 1959, 12, 942; D. T. Cromer and209 N. V. Belov, Krystallograjiya, 1960, 5, 16.210 J. V. Smith, Acta Cryst., 1959, 12, 516.5, 134.C .E. Olsen, ibid., p. 689486 CRYSTALLOGRAPHY.CaSiO,. That of pyroxmanganite (Mn, Fe, Ca, Mg)Si03 is very similar, butthe period of the chain contains seven tetrahedra.,ll The determinationof the structure of seidozerite has shown that, despite its orthosilicatestoicheiometric formula, it contains the Si,O, group, so that the formulashould be written Na,MnTi(Zr,.,T&.,)O,(F, OH),(Si,07)2. The structure ofhemimorphite, Zn,(OH),Si,O,, has also been dete1-mined.~l3 The basicstructure of celsian, BaA12,Si,08, is nearly isomorphous with that of ortho-clase, KA1Si,08, but the unit cell is doubled in one direction. There is agood approximation to an ordered arrangement of A1 and Si.21* Finally,we have space only to note the determinations of the structures of natroliteNa2Al,Si3010,2H,0, foshagi t e Ca,Si,O, (OH) zun yi t e Al,, (OH) 18Si,020C1,and hexagonal CaA12Si208.215The crystal structures of the borates CaB30,(OH),,2H,0 andCaB3O,(OH),,4H,O (inyoite) have been determined.216 Both contain thesame isolated polyions as were found in CaB,O,(OH)S,H,O (meyerhoff erite) ,217consi3ting of two (BO,OH), tetrahedra sharing a corner, with a B0,OHtriangle linking these to form a ring.w.c.3. ORGANIC STRUCTURESCarboxylic Acids and Related Compounds.-Recent studies of the crystalstructures of cis- and frans-long-chain cyclopropyl fatty acids have shownthat, whereas the molecules are straight in the trans-compound, yet in thecis-acids, they are bent at the cyclopropyl ring, producing a configurationlike a boomerang.Lactobacillic acid [( +)- or (-)-cis-11, Wmethylene-octadecanoic acid] and its raceinate possess this curious structurc.218 Thesimilarity in the single-crystal X-ray data of the cis-cyclopropyl acids andthe two cis-ethylenic acids, erucic and cis-nervonic, suggests a bent-chainconfiguration for these.219 In methyl stearate, there is no possibility ofhydrogen bonding, but the molecules form double sheets 220 like the normalfatty acids, whereas the ethyl and higher esters form single sheets. Thestructures of several methyloctadecanoic acids 221 have been determined,and a survey of the (&)-acids (from 2- to 17-methyl) indicates two basicforms.222 In one, the methyl branches are accommodated bctween theterminal methyl groups of the long carbon chains which therefore have a211 F.Liebau, W. Hilmer, and G. Lindemann, Acta Cryst., 1959, 12, 182; F. Tiebau,ibid., p. 177.213 V. I. Simonov and N. V. Belov, Krystallografiya, 1959, 4, 163.213 G. A. Barclay and E. G. Cox, 2. Krist., 1960, 113, 23.214 R. E. Newnham and H. D. Megaw, Acta Cryst., 1960, 13, 303.216 W. M. Meier, 2. Krist., 1960, 113, 430; J. A. Gard and H. I?. W. Taylor, Nature,1959, 183, 171; W. B. Kamb, Acla Cryst., 1960, 13, 15; Y. Takcuchi and G. Donnay,ibid., 1959, 12, 465.216 J. R. Clark, Acta Cryst., 1959, 12, 163; J. R. Clark and C. 1,. Christ, Z. Krist.,1959, 112, 213.217 J. R, Clark and C. L. Christ, Acta Cryst., 1956, 9, 830.218 B. M. Craven and G.A. Jeffrey, J . Amer, Ckem. SOC., 1960, 82, 3858; Acta Crysf.,219 B. M. Craven, J . Phys. Ckem., 1959, 63, 1296.220 S . Aleby and E. von Sydow, Acta Cryst., 1960, 13, 487.221 S. Abrahamsson, Arkiv Kemi, 1959, 14, 4.9; Acta Cryst., 1959, 12, 206, 301, 304.222 S. Abrahamsson, Arkiv Kemi, 1959, 14, 65.1959, 12, 754SUTOR: ORGANIC STRUCTURES. 487smaller angle of tilt than in the n-acids. In the other, the methyl group ispart of the straight chain starting from the carboxyl group. The remainingcarbon atoms form a side chain inclined to the other at 110".In tiglic (1) and angelic acids (2),223 intramolecular overcrowding andsteric hindrance appear to be relieved by displacement of the methyl groupattached to the @-carbon atom from the molecular plane, and by small dis-tortions in the bond angles.There is a short intramolecular contact,Me-CHMe-C-CO,H 11 (1)Me-CHH02C-C-MMeII (2)d(CH, - 0) = 2.8 A, in angelic acid, and any additional strain, placed onthe molecule by attempted substitution reactions, can cause isomerisationto the more stable tiglic acid. Three-dimensional refinements of fLsuccinicacid 224 and allokainic acid 225 have given more acceptable molecular dimen-sions. There is a preliminary report on the structure of mellitic acidC6(C0,H),.226 The stereochemistry of the acid radicals in rubidium di-hydrogen citrate and anhydrous citric acid is similar except for a displace-ment of one of the carbon atoms from the main aliphatic chain in the salt.227In the former, rubidium is co-ordinated with nine oxygen atoms,d(Rb - .0) = 2.90-3.25 A. In phenylarsonic the disposition ofthe bonds about the arsenic atom is very nearly tetrahedral with the averagevalue of AS-0) = 1.69 and d(As-C) = 1.90 A.The positions of all the atoms in sodium uranyl acetate have now beendetermined and a revised bond length-bond strength curve for UVI-0 ispre~ented.22~ Three-dimensional data collected by counter methods havebeen used in a refinement of the structure of basic beryllium acetate.24 Theatomic distances are d(C-C) = 1.500 0-006, d(C-0) = 1.264 & 0.008, andd(Be-0) = 1.666 & 0.004, 1.624 & 0.010 A. In copper salicylate tetra-hydrate,=O the copper atom is in a plane 4-co-ordination with two oxygenatoms of the water molecules in tmns-positions and two oxygens of thecarboxyl groups, d(Cu-0) = 1-92 and 1*84A, respectively.The other twocarboxyl oxygen atoms are outside the sphere of co-ordination, and thecompound is therefore not a chelate.An accurate three-dimensional analysis of thioacetamide 231 suggeststhat the molecule corresponds to the pure amide form S=CMe*NH,. Mole-cular dimensions are d(C--S) = 1.713 & 0.006, d(C-C) = 1.494, andd(C-N) = 1-324 both &0-008 A, L(C-C-N) = 117.7" & 0.6", L(S-C-C) =120.7", and L(S-C-N) = 121-6", both *0.4". N-Methylacetamide at -35" cis planar except for the hydrogen atoms.232 The high-temperature form2-23 A. L. Porte and J. M. Robertson, J., 1959, 817, 825.224 J. S. Broadley, D. W. J, Cruickshank, J.D. Morrison, J. M. Robertson, and225 D. TV. J. Cruickshank, Acta Crysf., 1959, 12, 1052.226 S. F. Darlow, Nature, 1960, 188, 542.227 C. E. Nordman, A. S. Weldon, and A. L. Patterson, Acta Cryst., 1960,13,414,418.228 A. Shimada, Bull. Chem. SOC. Japa?z, 1960, 33, 301.249 W. H. Zachariasen and H. A. Plettinger, Acta C ~ y s t . , 1959, 12, 526.230 F. Hank and J. Michalov, Acta Cryst., 1960, 13, 299.231 M. R. Truter, J., 1960, 997.232 J. L. Katz and B. Post, Acta Cryst., 1960, 13, 624.H. M. M. Shearer, Proc. Roy. Soc., 1959, A , 251, 441488 CRYSTALLOGRAPHY.probably shows molecular orientational disorder. The plane of the amidegroup is twisted 26" out of the plane of the benzene ring in benzamide,m aplanar configuration being unstable because of the proximity of non-bondedhydrogen atoms.A similar effect was observed in nicotinamide, but in thecorresponding acids, no such steric hindrance needoccur, and only a small angle of twist (<4") was H No;c<.) (3) found. In pyrazine-2-carboxyamide (3),234 there areno hydrogen atoms ortho with respect to theorientation of the NH, group, and the slight angle of tilt (5") of the amidegroup out of the plane of the pyrazine ring seems to be caused by othereffects.Other Acyclic Molecules.-At -1 19" C, dimethylacetylene 235 undergoesa phase transformation of the order-disorder type with respect to the tiltingof the molecular planes. Tetracyanoethylene is strictly planar,236 and bondlengths corrected for librational motion are d(C=C) = 1.317 & 0.009,d(C-C) = 1.454, 1.443 & 0-007, and d(C-N) = 1.15, 1.15 & 0-012 A.Ortho-rhombic hexatriacontane C,,H,4 237 is similar to the monoclinic form withmean values of d(C-C) = 1.533 & 0.022 A and L(C-C-C) = 112" & 1.8"for the planar zig-zag chain. meso-Erythritol has a traws-centrosymmetricalconformation about the central C-C bond.238 Both the outer C-0 and thecentral C-C bonds, and the two hydroxyl groups are in the gaztche-conform-ation with respect to the terminal C-C bond. The structure of lithiummethoxide can be considered ionic, though it has some features of a giantpolymer .239A careful X-ray study of anhydrous diacetylhydrazine (CH,*CO*NH), 240has shown that, except for two hydrogen atoms of the methyl group, themolecule, like diformyl hydrazine, is planar.The molecular dimensions arealso similar, d(N-N) = 1-396 & 0.009, d(C-N) = 1.341 3 0.008, d(C-0) =1.221 & 0.006, and d(C-C) = 1.504 -& 0.009 A. A planar configuration isalso adopted by trans-di(nitrosomethane) .241 Molecules of methylenebis-nitrosohydroxylamine in the dipotassium salt (4) have a 2-fold axis throughthe methylene group and L(N-C-N) = 104.9", slightly less than the tetra-hedral value.242 The dihedral angle formed between the planes of the twohalves of the molecule is 75.1". There is a lengthening of the C-N bond233 B. R. Penfold and J. C. B. White, A d a Cryst., 1959, 12, 130.234 Y. Takaki, Y. Sasada, and T. Watanabd, Acta Cryst., 1960, 13, 693.235 M. G. Miksic, E.Segerrnan, and B. Post, Acta Cryst., 1959, 12, 390.236 D. A. Bekoe and I(. N. Trueblood, 2. Krist., 1960, 113, 1.237 P. W. Teare, A d a Cryst., 1959, 12, 294.238 A. Shimada, Bull. Chem. SOC. Japan, 1959, 32, 326.239 P. J. Wheatley, Nature, 1960, 186, 681.240 R, Shintani, Acta Cryst., 1960, 18, 609.241 M. van Meerssche and G. Germain, Acta Cryst., 1959, 12. 818.242 J. H. Bryden, Acta Cryst., 1969, 12, 581SUTOR : ORGANIC STRUCTURES. 489[d(C-N) = 1-512 -+ 0-007 A] similar to that found in a number of amino-acids, emphasising the importance of resonance forms containing a positivelycharged nitrogen atom. In choline chloride (NMe,*CH,*CH,*OH) +C1-, thebond at which the molecule can be split by ionising radiation into trimethyl-amine and acetaldehyde has been observed with d(C-N) = 1.60 0.03 A,243but this may be a spurious effect of the radiation damage to the crystals.There are probably no hydrogen bonds in the structure, since the packingof the molecules seems to be dominated by ionic forces.The asymmetricunit of acetylcholine bromide 244 contains two distinct structural forms, anextended form and a " ring " structure where the choline radical formsan approximately planar " ring " with an intramolecular distance ofAromatic and Other Cyclic Compounds.-A number of over-crowdedaromatic molecules have been investigated, and the angle of tilt of the planeof the substituent group out of the plane of the aromatic ring has been foundin the following : 9,lO-dinitroanthracene (63.7"), 9-nitroanthracene (84.7"),nitromesitylene (66-4"), 9-anthraldehyde (27.0"), and 1,5-dinitronaphthalene(49°).245 Nitrobenzene is planar,246 according to a study at -30" c, thoughd(CH, * * * Oester) = 3 A.a twist of 9.3" has been reported for the nitro-groups in $-dinitrobenzene.The polynuclear hydrocarbons dibenzo[fg,qr]pentacene (5), tetra-benzo[de,hi,o$,st]pentacene (6), and the a-modification of the dibenzo-dinaphthapentacene (7) are considerably distorted,247 though in the first,the bond lengths are in good agreement with those predicted by molecular-orbital calculations for a planar molecule.In this crystal structure there isa short intermolecular contact with d(C - * * C) = 3-24 A, and in the othertwo, intramolecular overcrowding occurs between the non-bonded carbonatoms of adjacent rings, with d(C - * - C) about 2-96 A.The molecule of243 M. E. Senko and D. H. Templeton, Acta Cryst., 1960, 13, 281.244 H. Sorum, A d a Chem. Scaizd., 1959, 13, 345.245 J. Trotter, Acta Cryst., 1959, 12, 232, 237, 605, 922; 1960, 13, 96.246 J. Trotter, Acfa Cryst., 1959, 12, 884.a47 W. N. Lipscomb, J. M. Robertson, and M. G. Rossmann, J., 1959, 2601 : M. G.Rossmann, ibid., p. 2607; J. M. Robertson and J. Trotter, ibid., p. 2614490 CRY STALT-OGR APHY.P-1,2:4,5-tetrabromobenzene is planar,248 but the distance between adjacentbromine atoms is 3.377 3 0.004 A, representing an increase of 0.08 overthat in the hypothetical regular molecule.The structures of the monoclinic form of P-dichlorobenzene at - 140" c,a99-~yanoanthracene,~~O 9,1O-dichloroanthra~ene,~~~ and 9-bromo-10-ethyl-anthracene 252 have been determined, and three-dimen-sional refinements of the crystal structures of 9-benzo-quinone 253 and anthraquinone 254 have been carried out.Acepleiadylene (cyclohepta[fg]acenaphthylene) mole-cules (8) are disordered in the crystal str~cture,~55 theexact nature of the disorder being unknown.Unlike(8) azulene, 2-aminoazulene appears to have a regularand the bond lengths nearly correspond to aplane of symmetry perpendicular to the molecular plane.X-Ray and neutron-diffraction studies of 4,4'-dichlorodiphenyl sulphonehave produced results in good agreement .'O The chlorine and sulphur atomsshow slight but significant displacements from the plane of the benzene ring,and the dihedral angle between this plane and the C-S-C plane is 84-7" & 0.3".The predicted value is go", overlap of the 3d and 2$ orbitals of the sulphurand carbon atoms respectively being assumed.The value of d(S-C) =1.765 & 0.006 A is significantly less than the C-S single bond of 1.82 A,and appears to be remarkably constant whether the sulphur atom belongsto a sulphide, sulphoxide, or sulphone group. 1,1,2,2-TetrafIuoro-1,2-di-phenylethane is isostructural with biben~yl.~' The central C-C bond is1.539 -J-- 0.015 A, and the mean value of d(C-F) = 1.374 & 0.015 A.A series of papers describes the elucidation of the crystal structure of thered form of 5i-metho~y-2-nitrosophenol.~~~ The authors used opticaldiffraction principles and had no knowledge of the chemical configuration.The dimensions of the molecule are consistent with the o-benzoquinonemonoxime structure.In the crystalline state, hydrogen bonds link adjacentmolecules together whereas intramolecular hydrogen bonds have beenobserved in solution.258 The distribution of long and short bonds in a-2-chloro- and a-2-bromo-5-methyl-P-benzoquinone 4-oxime again excludes anitrosophenol structure.259 The oxime group is syn with respect to thechlorine atom.The structures of 1,3,5-trichlorobenzene at 20" and -183" c and 1,3,5-tribromobenzene at 20" c have been determined, and refined by using aniso-@248 G. Gafner and F. H. Herbstein, Acta Cryst., 1960, 13, 706.249 E, Frasson, C.Garbuglio, and S. Bezzi, Acta Cryst., 1959, 12, 126.250 H. Rabsud and J. Clastre, Acta Cryst., 1959, 12, 911.251 J. Trotter, Acta Cryst., 1959, 12, 54.252 C. Hauw, A d a Cryst., 1960, 13, 100,1. Trotter, Acta Cryst., 1960, 13, 86.254 k. V. R. Murty, 2. Krist., 1960, 113, 445.3G5 A. W. Hanson, .4cta Cryst., 1960, 13, 215.256 Y. Takaki, Y . Sssada, and I. Nitta, J . Phys. SOG. Japan. 1959, 14, 771.257 M. M. Crowder, K. A. Morley, and C . A. Taylor, Acta Cryst., 1959, 12, 108;G. W. K. Bartindale, M. M. Crowder, and K. A. Morley, ibid., p. 111.258 A. Burawoy, M. Cais, J. T. Chamberlain, F. Liversedge, and .4. R. Thompson,259 C. Romers and E. Fischmann, Acta Cryst., 1960, 13, 809.J., 1955, 3727SUTOR : ORGANIC STRUCTURES. 49 1tropic vibration factors.2@ Detailed refinements of di-9-xylylene 261 at 93"and 291" K have shown that, although the angle of bending (14") of thebenzene ring and the distance between the rings do not change with temper-ature, there is a decrease of 0-07 A in the aliphatic bond CH,-CH, and of0-03A in the length of the molecule with decrease in temperature.Thevibration amplitudes have been determined, and although these are muchreduced at the lower temperature, the pattern is unchanged.The asymmetric unit of cyclononylamine hydrobromide contains twomolecules 262 which are conformational isomers of each other. Cyclo-dodecane has a disordered structure and either of two conformationalisomers will fit the observed data.263 In 1,6-trn~zs-diaminocyclododecanedihydrochloride, the carbon skeleton does not deviate significantly from2/m (C2,) symmetry.264Heterocyclic Compounds.-In pyrazole, 265 the bond lengths indicate alarge contribution to the resonance hybrid of the betaine form which con-tains a positively charged nitrogen atom.The crystal structure consists ofmolecules hydrogen bonded together forming a figure-of-eight spiral. Thebond lengths obtained from an analysis of pyrimidine 266 have been correctedfor thermal motion. The only departure from rnm symmetry of the moleculeoccurs in the two C-C bonds [d(C-C) = 1-41, 1-35 & 0.007 A]. The crystalstructure of nickel xtioporphyrin I1 267 has been determined, and a three-dimensional refinement of that of dioxopiperazine 268 has been carried out.The azo-bridge of 4,4'-trans-azopyridine N-oxide is almost a pure doublebond with d(N-N) = 1.228 & 0.15 A and L(C-N-N) = 113.3" & O-6°.269A comparison with the parent substance 4-nitropyridine N-oxide suggests achange in the ring from quinoidal to aromatic behaviour brought about bydiazotisation.The weighted mean bond lengths of the two crystallographically distinctmolecules in acridine I1 270 agree with those observed in acridine 111.The two molecules exhibit significant departures from planarity, the centralring of one being in the " chair " configuration, and that of the other in the" boat " form.1,2:8,9-Dibenzacridine does not appear to be strictly planar,and chemically equivalent C-C and C-N bonds have a root-mean-squaredeviation of 0.014 A from the mean ~ a l u e .~ 5 The heterocyclic rings in thehydrochlorides of piperidine and piperazine are in the " chair "In the light of some X-ray work on 2-phenyli~oisatogen,~~~ the structureof 2-phenylisatogen osinie has been reexamined and shown to be a normal260 H. J. Milledge and L. M. Pant, Acta Cryst., 1960, 13, 285.261 I<. Lonsdale, H. J. Milledge, and K. V. Krishna Rao, Proc. Roy. Soc., 1960,262 K. F. Bryan and J. D. Dunitz, Helv. Chim. Acfn, 1960, 43, 3.263 J. I). Dunitz and EI. M. AT. Shearer, Helv. Claim. Acta, 1960, 43, 18.2G1 E. Huber-Buser and J. D. Dunitz, Helv. Chint. Actn, 1960, 43, 760.265 H. W. W. Ehrlich, Acta C ~ y s t . , 1960, 13, 946.2c6 P. J. Wheatley, Acta Cryst., 1960, 13, 80.267 M . B. Crute, Acfa Cryst., 1959, 12, 24.268 R.Degeilh and R. E. Marsh, Acta Cryst., 1959, 12, 1007.m9 E. L. Eichhorn, Acta Cryst., 1969, 12, 746.270 D. C. Phillips, F. R. Ahmed, and W. H. Barnes, Acta Cryst., 1960, 13, 365.871 C. Rkrat, Acta Cryst., 1960, 13, 72, 459.272 J. L. Pinkus, T. Cohen, M. Sundaralingam, and G. A. Jeffrey, Proc. Chew. Soc.,A , 255, 82.1960. 70492 CRYSTALLOGRAPHY.C-oxime of the former (9), which is consistent with its infrared spectrumand chemical properties. Isoindigo is planar and adopts the trans-con-figuration.273 In l-oxa-azulan-2-0ne~~~~ the distribution of long and shortbonds (mean values 1.40 and 1.35 A) suggests a preponderance of the y-lactone form in the resonance hybrid.An anisotropic refinement of the crystal structure of 4-methyl-lJ2-dithia-cyclopent-4-ene-3-thione (10) 275 has shown that the carbon atom of thePh*C=NOHmethyl group has thermal parameters about 40% greater than those of thecarbon atoms in the five-membered ring.The effect is due in part to themethyl group's being statistically displaced by 0-1 A out of the plane ofthe ring because of a close intramolecular contact, d(CH, - - S) = 3.23 A.In both 3,3'-diethylthiacarbocyanine bromide (11) and its ethanol s o l ~ a t e , ~ ~ ~ ~ ~ c = c H - c H = CH-NEt( 1 ' )E tBr'the conjugated chain is extended and the sulphur atoms are cis with respectto this chain. The cation is planar in the former, but in the latter the atomslie in two planes inclined at about 8" (in both cases the methyl groups of theethyl substituents being excluded).In the dibromide and di-iodide of 5,10-dihydro-5,10-dimethyl-arsanthrenJZ7' molecules are folded about the As-As axis.The halogensare disposed on opposite sides of, and at right angles to, the plane of thethree As-C bonds with d(As-Br) = 2.59, 2-66 0.01 and d(As-I) = 2.80,2-98 & 0.01 A. The valencies of the other arsenic atom are probably non-planar as in other 3-covalent arsenic compounds.Molecular Compounds.-Quinol and acetone form a molecular compoundrather than a clathrate or channel structure.278 Infinite chains of alternatequinol and acetone molecules are joined by hydrogen bonds of 2.74 A. Thistype of complex is apparently specific to acetone. Larger or smaller mole-cules probably fail to form the necessary hydrogen bonds, or to utilise thespace efficiently.In the cyclohexa-amylose-iodine complex ,279 a cylindricalor torus-like carbohydrate molecule is coaxial with and encloses each iodinemolecule. Packing considerations have led to the values of 13 A for thediameter of the torus and 6.7 The co-ordination poly- for the thickness.273 H. von Eller-Pandraud, Acta Cryst., 1960, 13, 936.274 Y. Sasada, Bull. Chem. SOL. Japan, 1959, 32, 165, 171.275 G. A. Jeffrey and R. Shiono, Acta Crysf., 1959, 12, 447.27Q P. J. Wheatley, J., 1959, 3245, 4096.277 D. J . Sutor and F. R. Harper, Acta Cryst., 1969, 12, 585.278 J. D. Lee and S. C. Wallwork, Acta Cryst., 1959, 12, 210.e79 W. J . James, D. French, and R. E. Rundle, Acta Cryst., 1959, 12, 385SUTOR : ORGANIC STRUCTURES. 493hedron around the central selenium atom in the addition compoundSeOC1,,2C5H,N is a tetragonal pyramid.280 This represents the first exampleof five-bonded selenium, and the usual function of an oxychloride as a donormolecule is reversed.Two carbon atoms, one belonging to the lactone ringand the other to a CO group, form bridges between the two cobalt atoms inthe complex of the empirical formula CO,(CO),,HC~CH.~~~ These four atomsare not coplanar and it is suggested that their generally accepted planararrangement in dicobalt octacarbonyl should be revised.Natural Products and Related Compounds.-The stereochemistry ofaureomycin has been determined by the elucidation of the crystal structureof its hydrochloride.282 The dimethylamino-group takes the polar ( E ) con-figuration with respect t o the ring t o which it is attached. The structurethus corresponds to the conformation assigned on chemical grounds toepiaureomycin.The structure of the hemlock alkaloid +-conhydrinehydrobromide has been determined with some precision.2s3 The hydroxyland the propyl group are trans with respect to each other and equatorial tothe saturated six-membered ring. The absolute configuration is still indoubt. The stereochemical arrangement suggested recently by chemicalmethods for ibogaine, an indole alkaloid, has been confirmed except for asubstituent ethyl group which is cis and not trans with respect to the iso-quinuclidine nitrogen atom,.284 The compound has been studied as thehydrobromide, and the bromine ion is co-ordinated to an indole and an iso-quiiiuclidine nitrogen on different molecules a t distances of 3.34 and 3.24 krespectively.The difference is significant and in accordance with the greaterbasicity of the latter nitrogen atom. The work on (&)-alphaprodine hydro-chloride 285 and (-)-aspidospermine N(b)-methiodide 286 confirms the modelsdeduced from chemical evidence apart from thelocation of an ethyl group in the latter. The struc-ture of calycanthine has been determined simul-taneously by X-ray and chemical meth0ds.~8' Themolecule (12) consists of two benzene rings inclineda t about 60" to each other; the other four six-membered rings are all of the '' chair " form and arefused cis to each other.There are preliminaryreports of the work on isoclovene,288 gelsemine hydrochloride and hydro-bromideJB9 ce~ine,~~O demethanol aconinone hydriodide t r i h ~ d r a t e , ~ ~ ~ and(,2) N \H Me iiv?280 I. Lindqvist and G. Nahringbauer, Acta Cryst., 1959, 12, 638.281 0. S. Mills and G. Robinson, Proc. Chem. Soc., 1959, 156.282 S. Hirokawa, Y. Okaya, F. M. Lovell, and R. Pepinsky, Acta Cryst., 1959,283 H. S. Yanai and W. N. Lipscomb, Tetrahedron, 1959, 6, 103.284 G. Arai, J. Coppola, and G. A. Jeffrey, Acta Cryst., 1960, 13, 553.285 G. Kartha, F. R. Ahmed, and W. H. Barnes, Acta Cryst., 1960, 13, 525.286 J. F. D. Mills and S. C. Nyburg, J., 1960, 1458.287 T. A. Hamor, J. M. Robertson, H. N. Shrivastava, and J, V.Silverton, Proc.Chem. Soc., 1960, 78; R. B. Woodward, N. C. Yang, T. J. Katz, V. M. Clark, J. Harley-Mason, R. F. J. Ingleby, and N. Sheppard, ibid., p. 76.288 J. S. Clunie and J . 111. Robertson, Proc. Chenz. SOC., 1960, 82.289 F. M. Lovell, R. Pepinsky, and A. J. C. Wilson, Tetrahedron Letters, 1959, 4, 1.290 W. T. Eeles, Tetrahedron Letters, 1960, 7, 24.291 M. Przybylska and L. Marion, Canad. J . Chem., 1959, 57, 1116.12, 811494 CRYSTALLOGRAPHY.jacobine br~mohydrin.~~~ The stereochemistry of the plant estrogenmiroestrol has been determined by an X-ray analysis of the bromide.293The trans-isomer of p-ionylidenecrotonic acid (13) not only forms a stepin the synthesis of vitamin A, but also comprises most of the features foundgenerally in the carotenoids, a group of natural pigments.The conjugatedside chain is built of joined '' isoprenic " links, and since it is all trans, the0 6;;: CH. m e : CH. CH:CW. c',OHcorresponding part of the vitamin A molecule can be assumed to be alsotrans.294 The second of a series of papers describing the X-ray work onvitamin B,, and related substances has now appeared.295A number of amino-acids have been investigated. An accurate analysisof P-glycine 296 has shown that the bond lengths and angles are probably notsignificantly different from those in the a-form. The ferroelectric phase oftriglycine sulphate 297 can best be described as glycine diglycinium sulphatebecause of the existence in the crystal of the forms(NH,*CH,CO*O) (NH,*CH,*CO*OH) &30,2-.There is a strong hydrogen bond of length 2-43 A between the oxygen atomof the carboxyl group of the zwitter-ion glycine and that of one of the planarglyciniuni ions.Hexagonal L-cystine 298 consists of glycine-like sheets withthe C-R bonds pointing alternately up and down in successive sheets whichare linked together in pairs by disulphide bridges of dimensions d(S-S) =2.032 &- 0.004 and d(S-C) = 1.820 & 0-012 A. There are close van derWaals contacts between each sulphur atom and its non-bonded neighbouringatoms, and a revised value of 1.65 A for the van der Waals radius of sulphuris suggested. The dimensions of the sulphur bridge in L-cystine dihydro-bromide zs9 are d(S-S) = 2.024 & 0.014 and d(S-C) = 1 . 8 6 2 5 0.021 A.In L-serine phosphate,30° the C-N bond of 1.468 A is shorter than in serineand threonine and, as in glycine, does not differ significantly from thenormal value of 1.47 A.Several papers describing the work on the units of the nucleic acids haveappeared.2-Deo~yribose,~~~ the sugar of DNA, has been shown to havethe pyranose structure with the normal staggered " chair" form. The292 J. Fridrichsons, A. McL. Mathieson, and D. J. Sutor, Tetrahedron Letters, 1060,23, 35.293 N. E. Taylor, D. C. Hodgkin, and J. S. Rollett, J., 1960, 3685.293 E. L. Eichhorn and C. H. MacGillavry, Actu Cryst., 1959, 12, 872.295 D. C. Hodgkin, J. Pickworth, J. H. Robertson, R. J. Prosen, R. A. Sparks, andZ96 Y. Iitaka, Acla Cryst., 1960, 13, 35.297 S. Hoshino, Y.Okaya, and R. Pepinsky, Phys. Rev., 1959, 115, 323.sg* B. M. Oughton and P. M. Harrison, Acta Cryst., 1959, 12, 396.299 J. Peterson, L. K. Steinrauf, and L. H. Jensen, Acta Cryst., 1960, 13, 104.300 G. H. McCallum, J. M. Robertson, and G. A. Sim, Nature, 1959, 184, Suppl. 24,301 S, Furberg, Acta Chem. Scund., 1960, 14, 1357.K. N. Trueblood, Proc. Roy. Soc., 1959, A , 251, 306.1863GREEN: PROTEINS. 495sugar belongs to the p-series, the conformation being lax3ep4ax. In cytidylicacid b (14),302 the puckering in the ribose ring differs from that in othernucleotides and nucleosides whose crystal structures have been determined.Ctr) is 0.5 A from the plane of the sugar defined by CCl'>, 0(1'1, C(3'), and C(4')so that its oxygen atom O(,,) is brought close to the plane. In cytidine,adenosine 5'-phosphat~,~~3 and calcium thyinidylate (a 5'-phosphate) J304C(3') is 0.5 I t should be noted that in cytidylicacid b, the phosphate group is attached to the 3'-position.A note on the hydrogen-bonded complex of l-methylthymine and9-methyladenine 305 reports a different hydrogen-bond arrangement betweenthese bases irom that proposed by Crick and Watson for adenine and thyminein DNA.The NH - * * 0 bond is maintained, but the nitrogen atom ofl-methylthymine is bonded to the free nitrogen atom in the imidazole ringof 9-methyladenine rather than to the nitrogen of the pyrimidine ring.from the plane of the sugar.D. J. S.4. PROTEINSTwo achievements stand out in the gencral progress of crystallographicstudies of proteins since the last Report of this series: 306 a three-dimensionalelectron-density map of myoglobin at 2 and a three-dimen-sional map for hanoglobin a t 5.5 f , resolution.308 These results will bedescribed in detail later, but liere we may note that the map of myoglobinis fine enough for features of great chemical interest to be identified, whilethe hanoglobin map provides a fascinating model of the integration offunctional sub-units into a more effective whole. The importance of thiskind of geometrical information for an understanding of mechanisms inbiology can hardly be overestimated.A typical problem is the specificity ofenzymes, where interaction with substrate molecules depends on preciselydefined spatial arrangements; another is the masking of antigens by match-ing antibodies.X-Ray diffraction is the one technique capable of revealing the structurein sufficient detail, but the information in the diffraction patterns could notbe extracted until a direct method of phase determination was found.The302 E. Alver and S. Furberg, Acta Chem. Scand., 1959, 13, 910.303 J . Kraut and L. H. Jensen, Nature, 1960, 186, 798.304 P. Horn, V. Luzzati, and K. N. Trueblood, Nature, 1959,183, 880.3O5 K. Hoogsteen, Acta Cryst., 1959, 12, 822.306 G. A. Sim and J. C . Spealrman, Ann. Reports, 1958, 55, 430.307 J. C. Kendrew, R. E. Dickerson, B. E. Strandberg, R. G. Hart, D. R. Davis,308 M. F. Perutz, 31. G. Rossmann, A. 1;. Cullis, H. Muirhead, C. Will, and A. C . T.D.C. Phillips, and V. C. Shore, Nature, 1960, 185, 422.North, Nature, 1960, 185, 416496 CRYSTALLOGRAPHY.technique of isomorphous replacement with heavy atoms first gave resultswith h ~ e m o g l o b i n , ~ ~ ~ ~ ~ ~ ~ and was rapidly developed to obtain a low-resolutionelectron-density map of myoglobin in which a chemically known feature,the h2m group, was recognised for the first time.311 Both events were dulynoted in these Reports: the first in the comprehensive survey of biologicalmacromolecules by Bernal and Carlisle in 1955,312 the second in the lastReport, that for 195fL306 Other reviews which have dealt particularly withthe progress of protein crystallography are those by Kendrew and P e r u t ~ , ~ l ~Kendrew and CrickJ314 and Rich and Green.315Before discussing the proteins themselves, we shall say something ofdevelopments in the isomorphous replacement technique. The principlesof the method have been fully described by Harker 316 and Kendrew andCrick,314 and will not be detailed here, except to note that at least two deriv-atives isomorphous with the unmodified protein are needed. In the inter-pretation the first task is to determine the positions of the various heavyatoms in the unit cell.In favourable cases of centrosymmetry this can bedone by difference Patterson method^,^^*^^^ but new correlation functionswere developed to deal with non-centric situations in hzmoglobin and myo-For some reflections in the diffraction pattern the scatteringcontributions of the heavy atoms in one pair of derivatives may be too smallto provide reliable information about the phases; also, random errors inmeasuring the intensities make the determinations less certain.Thesedifficulties can be overcome by using more than the minimum of two iso-morphous replacements, and combining the various phase indications withdue regard for the errors in intensity The final set ofFourier coefficients from which the electron-density map is computed willcontain phases which vary widely in their reliability. In this situation it isbest to weight each amplitude according to the probable accuracy of theassociated phase. The weighting function which reduces the mean-squareerror of the electron density to a minimum has been derived by Blow andCrick 322 and by Sim.323Further developments of the crystallographic technique will be aimed atreducing the requirement for several heavy-atom derivatives.In particular,it seems likely that greater use will be made of anomalous dispersion methods,309 D. W. Green, V. M. Ingram, and M. F. Perutz, Proc. Roy. Soc., 1954, A , 225, 287.310 W. L. Bragg and M. F. Perutz, Pvoc. Boy. Soc., 1954, A, 225, 315.311 J. C. Kendrew, G. Bodo, H. M. Dintzis, R. G. Parrish, H. W. Wyckoff, and313 J. D. Bernal aiid C. H. Carli.de, Ann. Refiovts, 1955, 52, 380.313 J. C. Kendrew and M. F. Perutz, Ann. Rev. Biochem., 1957, 26, 327.314 J. C..Kendrew and F. H. C. Crick, Adv. Protein Chem., 1957, 12, 134.315 A. Rich and D. W. Green, Anl-2. Rev. Biochem., in the press.316 D.Harker, Acta Cryst., 1956, 9, 1.317 M. M. Bluhm, G. Bodo, H. M. Dintzis, and J. C. Kendrew, Proc. Roy. Soc.,318 M. F. Perutz, Actu Cryst., 1956, 9, 867.319 G. Bodo, H. M. Dintzis, J. C. Kendrew, and H. W. Wyckoff, Proc. Roy. SOC.,320 M. G. Rossmann, Acla Cryst., 1960, 13, 221.321 W. L. Bragg, Acta Cryst., 1958, 11, 70.322 D. M. Blow and F. H. C. Crick, Acta Cryst., 1959, 12, 794.323 G. A. Sim, Actu Cryst., 1960, 13, 511.D. C. Phillips, Nature, 1958, 181, 662.1958, A, 246, 369.1959, A , 253, 70GREEN: PROTEINS. 497made more profitable by the increased accuracy of intensity measurementavailable from counter diffractometers.Results.-The lack of systematic methods for preparing heavy-atomderivatives remains an obstacle in the way of structure determinations formany proteins, and there is very little progress to report in this importantfield.Sulphydryl (mercapto-)groups provided a means of attaching mer-curials to hzmoglobin, but several small proteins which are being studiedcrystallographically do not contain cysteine. For enzymes there is anattractive opportunity to use heavy-atom-containing analogues of the usualsubstrates, which should be bound at the active site. The only example ofthis reported so far is a derivative of ribonuclease prepared with mercuratedcytidylic Analogous attempts to exploit the affinity of the hzmgroup in myoglobin for imidazoles, isocyanides, and nitroso-compounds werepartially successful, but did not provide a convenient heavy-atom derivativebecause the various ligands were displaced by atmospheric oxygen.317The useful derivatives of myoglobin, and non-sulphydryl derivatives ofhzmoglobin, were prepared by crystallising the protein from concentratedammonium sulphate solutions in the presence of one or two equivalents ofvarious heavy-metal ions.The reagents which gave specific binding at oneor two sites included K,Hg14, KAuCl,, AgNO,, p-C1Hg.C,H4*S03H, and“ mercury diammine,” prepared by dissolving mercuric oxide in hot con-centrated ammonium sulphate s o l ~ t i o n . ~ ~ ~ . ~ ~ ~ The chemistry of the inter-action is in no case understood, but a definite specificity is indicated by thefinding that K2HgI, and KAuC1, are bound to sperm whale myoglobin andseal myoglobin in corresponding positions on the molecule, even though thecrystal forms are different.325Myog1obin.-The electron-density map for myoglobin at 6 A res~lution,~~lmentioned in the previous Report, showed the position of the hzm groupand the general run of the polypeptide chain, but some breaks in the con-tinuity of the high electron density made it impossible to trace a uniquepath through all the ‘‘ rods ” representing the complete molecule.Kendrewand his co-workers have now extended the resolution to 2 a task requir-ing the measurement of some 10,000 reflections for the native protein andeach of four derivatives. All the associated phase-determining calculationsand Fourier syntheses were carried out on the Cambridge EDSAC I1 com-puter. The result gives, for the first time, a detailed impression of thestructure of a globular protein.Atoms connected by covalent bonds arenot resolved from one another, but groups in van der Waals contact aredistinctly separated, and can be recognised if they are sufficiently large andcharacteristic, like the indole group of tryptophan or the irnidazole of hist-idine. The single polypeptide chain can now be traced as a continuousthread of high electron density. Where there were solid rods of density inthe 6 A map, the main chain is seen to form a helix with a radius of 2 A,leaving a hollow core. Fig. 9 shows the electron density in the wall of oneof these tubes, as a projection on to a cylindrical surface at 1.95 A radius,as4 M. V. King, Summary of Papers, 5th International Congress of Crystallography,325 H.Scouloudi, Proc. Roy. SOL, 1960, A , 258, 181.Cambridge, 1960498 CRYSTALLOGRAPHY.which has then been cut parallel to the axis and spread out flat. Super-imposed on the- contours of electron density is a similar projection of askeletal a-helix, with the standard pitch of 5.4 A and 3.6 residues per turn.326FIG. 9. (a) Cylindrical projection of a helicalscgment of potypeptide chain from the 2 Aelectron-density map of myoglobin, with askeleton of the u-helix superposed.(b) Key to the arrangement of atoms in thcu-helix. The points marked /3 and /3‘ arethe two alternative projected positions of Cp. Is’ i s the position in a left-handed, and j3that in a right-handed helix.(Reproduced, with permission, from J.C.Kendrew, R. E. Dickerson, B. E. Strand-berg, R. G. Hart, D. R. Davies, D. C .Phillips, and V. C. Shore, Nature, 1960,185, 422.)A similarly impressive fit is found over three-quarters of the polypeptidechain, leaving no doubt that the a-helix is the most important single prin-ciple of the folding. A count of the numbers of residues in the helices andFIG. 10. Distribution of aniino-acid residues among the a-helical lengths and ‘ I corners I ’u-Helical sections are indicated by the in the molecule of sperm-whale nzyoglobin.double line.in the “ corners ” between them has recently been made,327 and the resultis shown in Fig. 10. All the lengths of helix are right-handed: the firstatom of each side chain, Cp, can be seen projecting from the main chain inthe direction opposite to the carboxyl C-0 bond, as expected for L-amino-L.Pauling, R. B. Corey, and H. R. Branson, Proc. Nut. Acad. Sci. U.S.A.,1951, 37, 205.s27 J. C . Kendrew, personal communicationGREEN : PROTEINS. 499acids in a right-handed helix. Also, the sense of the helix is obvious fromthe C-0 direction, so the amino- and carboxyl ends can be identified.At present little can be said about the configurations at the “ corners.”The only residue which would necessarily break the regular hydrogen bond-ing of the or-helix is proline, but chemical analysis shows only four prolineresidues in n i y o g l ~ b i n , ~ ~ ~ and there are seven corners. One proline doesappear to be the sole hinge at a sharp corner (marked 0 in Fig.lo), but twoothers which have been identified take part in quite long non-a-helicalsections .329The hzrn group appears to be very precisely attached to the protein,making contact at the edges with several lengths of a-helix, and hydrogenbonded through the propionic acid side chains. Its orientation as measuredon the electron-density map agrees closely with that found earlier by electronspin resonance measurements.330 As had been expected on chemicalgrounds, one of the six co-ordination positions of the iron atom is occupiedby a nitrogen atom of a histidine side chain, with the imidazole ring per-pendicular to the hzm plane (Fe-N = 1-9 A), while the position opposite this,presumably occupied by the oxygen molecule in oxymyoglobin, is markedby a small peak of elcctron density probably representing a water molecule.The electron-density map shows many other features which have yet tobe evaluated in detail.Chemical analysis of the sequence is also beingcarried out, and already a large measure of correlation has been establishedbetween the peptides and the map.329 A further stage of the X-ray analysisis now being undertaken to include the remaining measurable reflections ofthe diffraction pattern, extending out to 1-5 i% spacing.Haemog1obin.-Progress with the -X-ray analysis of hzmoglobin washeld up for some time by the lack of suitable heavy-atom derivatives, butPerutz and his colleagues have now obtained a three-dimensional electrondensity map at 5.5 A resolution based on phase determinations for 1200reflections.308 Though the resolution is slightly better than that of the firstthree-dimensional map of myoglobin, this map provides essentially the samekind of information, viz., the general run of the polypeptide chains and thepositions of the hzrn groups.Haemoglobin has four polypeptide chains, which are revealed as distinctsub-units arranged tetrahedrally.The crystal symmetry requires them tobe identical in pairs, in agreement with chemical studies,331 but the twounrelated types of chain have now also been found to be very similar; andboth resemble the conformation of the myoglobin chain closely. This re-markable result suggests an interesting evolutionary connection between thetwo proteins. Each sub-unit carries its hzm group in the same positionand orientation relative to the polypeptide chain as in myoglobin.Again,electron spin resonance measurements have established the hzm orient-ations very accurately.s232* A. B. Edmundson, and C. H. W. Hirs, Fed. Proc., 1959,18, 220.32% J. C . Kendrew, to be published, 1961.330 D. J. E. Ingram and J. C. Kendrew, Nutuw, 1956, 178, 905.331 H. S. Rhinesmith, W. A. Schroeder, and N. Martin, J . Amer. Chem. Soc., 1958,332 D. J. E. Ingram, J. F. Gibson, and &‘I. F. Perutz, Nature, 1966, 178, 906.80, 3358500 CRYSTALLOGRAPHY.Since the amino- and carboxyl ends of the chain can be identified byanalogy with myoglobin, and thewhole chain can be traced from one end tothe other without a break, it should soon be possible to make a test of thehypothesis that the folding of proteins is ‘‘ coded’’ in the sequence ofresidues, by comparing sequence patterns and conformations in hzmoglobinand myoglobin.This seems likely to be a major topic of the next Report,for already the sequence of the first 31 residues from the amino-end of thep-chain in human hzmoglobin has been determined.=In the complete molecule the four sub-units pack together very intimatelyand symmetrically, with not only the true crystallographic dyad axis passingbetween them, but also two approximate dyads making up an orthogonalThe four hzm groups lie at the vertices of a distortedA as the shortest distance between iron atoms. Theseset (point group 222).tetrahedron with 25.2FIG. 11. Arrangement of the ham and sulphhydryl (rnercupto-) groups in hamoglobin.Arrows indicate the reactive side of each ham.(Reproduced, with permission, from M. F. Perutz, M. G. Rossmann, A. F. Cullis,H. Muirhead, G. Will, and A. C. T. North, Nature, 1960, 185, 416.)large separations were not expected, since the co-operative interaction ofhaems in the oxygenation reaction had previously been explained by mechan-isms of steric hindrance between close pairs of hzms. Fig. 11 shows thearrangement schematically, and includes the sulphhydryl groups, which areknown to be involved in the hzm-hzm interaction.334 The haemoglobin andmyoglobin results taken together suggest a long path of interaction betweentwo hzems on non-identical chains, via the hzm-linked histidines to the mainpolypeptide chain and through the SH-group from one chain to the other;but details of this must await an electron-density map at higher resolution.Other Proteins and Viruses.-No results comparable with those fromhaemoglobin and myoglobin are yet available for other proteins, thoughmany attempts are being made to prepare heavy-atom derivatives withwhich the same methods of analysis can be used. The determination of thecomplete sequence of amino-acid residues in ribonuclease 335,336 has led to333 G. Braunitzer, N. Hilschmann, and R. Muller, 2. PhysioZ. Cham., 1960, 318, 284.334 A. F. Riggs and R. A. Wolbach, J . Gen. Physiol., 1956, 39, 585.335 C. H. W. Hirs, S. Moore, and W. H. Stein, J . Biol. Chem., 1960, 235, 633.336 D. H. Spackman, W. H. Stein, and S. Moore, J . Biol. Chem., 1960, 235, 648GREEN : PROTEINS. 501an ingenious proposal for the conformation 337 in which numerous side-chaininteractions determine the arrangement of several a-helical lengths. Themost recent X-ray studies of this protein 338~339 do not bear directly on thisproblem, but earlier work showed that the structure was of a differenttype from that of hzmoglobin and myoglobin,aO and was unlikely to containany long a-helical sections.=lIn preliminary studies it is sometimes possible to show that a proteinmolecule is made up of sub-units arranged in a symmetrical way. Recentexamples of this are apoferritin and ferritin B where there are 24 sub-unitsarranged in the cubic point group 432,a2 also P-lactoglobulina3 and oxhzemoglobin,344 both with two sub-units related by a dyad axis.The rules of symmetry provide particularly important clues to the struc-tures of viruses; 345 and this is a field where observations in the electronmicroscope and deductions from the X-ray diffraction data are being broughttogether very profitably. Five-fold cubic symmetry (point group 532),which requires the virus particle to be divisible into sixty geometricallyequivalent parts, has been demonstrated by X-ray diffraction for the virusesof tomato bushy stunt ,346 turnip yellow m0saic,3~~,~* southern bean mosaic,349and poliomyelitis.350 In the case of turnip yellow mosaic virus the electronmicroscope has shown 32 morphological sub-units arranged at the verticesof a semi-regular polyhedron with 532 ~ y m m e t r y . ~ ~ ~ . ~ ~ ~ They are of twodistinct types : twelve lying on five-fold axes, and twenty on threefold axes,so the total number of sub-units is at least 120. Chemical end-group deter-minations are not yet sufficiently accurate to enable each type of sub-unitto be identified with one or two polypeptide chains.Isomorphous replacement should also be a powerful technique in thesecrystallographic studies of viruses, since the sub-unit molecular weight isquite comparable with that of small proteins. Already, interesting resultshave come from its application to tobacco mosaic virus, and we can expectfurther successes in the near future.D. W. G.W. COCHRAN.D. W. GREEN.D. J. SUTOR.337 H. A. Scheraga, J . Amer. Chem. Soc., 1960, 82, 3847.338 J. D. Bernal and C. H. Carlisle, Acta Cryst., 1959, 12, 221.339 J . D. Bernal, C. H. Carlisle, and M. A. Rosemeyer, Actu Cryst., 1959, 12, 227.340 U. W. Arndt and D. P. Riley, Phil. Trans., 1954, A , 247, 409.341 B. Magdoff, F. H. C . Crick, and V. Luzzati, Actu Cryst., 1956, 9, 156.342 P. M. Harrison, J. Mol. Biol., 1959, 1, 69.343 D. W. Green and R. Aschaffenburg, J. Mol. Biol., 1959, 1, 54.344 A. C. T. North, Acta Cryst., 1959, 12, 512.345 F. H. C. Crick and J. D. Watson, Nature, 1956, 177, 473.346 D. L. D. Caspar, Nature, 1956, 177, 475.347 A. Klug, J. T. Finch, and R. Franklin, Biochim. Biophys. Acta, 1957, 25, 242.348 B. E. Magdoff, Nature, 1960, 185, 673.34D J. T. Finch and A. Klug, Nature, 1959, 183, 1703.350 A. Klug and J. T. Finch, J . Mot. Biol., 1960, 2, 201.851 H. E. Huxley and G. Zubay, J. Mol. Biol., 1960, 2, 189.352 H. L. Nixon and A. J. Gibbs, J. Mol. Biol., 1960, 2, 197

ISSN:0365-6217    

DOI:10.1039/AR9605700462

出版商:RSC    

年代:1960

数据来源: RSC

摘要:

INDEX OF AUTHORS’ NAMESAbdalla, A., 444.Abel, E. W., 127, 144, 149.Abel, G. J., jun., 444.Abella, M. G., 418.Abercrombie, M. J., 350.Abood, L. G., 391.Abou-Eluaga, M. A., 416,Abraham, E. P., 268.Abraham, M. H., 164.Abraham, N. A., 243.Abraham, R. J., 73, 194.Abrahams, S. C., 463, 469.Abrahamsson, S., 486.Abranis, R., 304, 361, 364.Abramyan, A. h., 452.AbrZo, A., 440.Acerbo, S. N., 237.Acheson, G. H., 392.Acheson, R. M., 56, 195,Ackerman, L., 91.Ackermann, G., 416.Ackman, R. G., 218.Adam, F. C., 77.Adams, D. M., 145, 151.Adams, E. P., 261.Adams, G. A., 350.Adams, R., 196.Adamson, A. W., 141.Adcock, B., 56, 195.Addison, C. C., 115, 162.Aditsa, S., 96.Adler, J., 304, 353, 355,Adler, T. I<., 194.Adlerovh, E., 286.Adriaanse, N., 10.Adrian, F.J., 70, 73.Adrian, R. H., 383.Aebi, H., 386.Affsprung, H. E., 420.Afonso, A., 293.Aftandilian, V. D., 154.Aggarwal, S. L., 113.Agnello, E. J., 201, 306.Agnihotri, R. I<., 200.Agre, C. L., 219.Agron, P. A., 80, 133.Aguilar-Santos, G., 285.Aguiler, V., 368.Ahlbeck, R. A., 105.Ahmad, A,, 276.Ahmad, Rf. S., 244.Ahmad, V., 286.Ahmed, F. R., 491, 493.Ahrens, E. H., jun., 217.Ahrens, L. H., 434.Aiman, C. E., 270.430.276.356.Ainscough, J. B., 174.Akhtar, M., 216.Akhtar, S., 196.Akishin, P. A., 26, 131.Akiyoshi, S., 252.Alauddin, M., 286.Alberola, A., 142.Albers, F. C., 132.Albers, R. W., 368.Albersheim, P., 350.Albert, A., 194, 277.Alberts, B. M., 304.Alberty, R. A., 91, 92, 94.Albrecht, A.C., 51, 105.Albright, C . D., 392.Alcock, C. B., 159.Alden, K. I., 132.Alder, E., 234, 235.Alder, I<., 236, 245.Alderman, P. R. H., 145,Alderweireldt, F., 259.Aldridge, C. L., 147.Aleby, S., 486.Aleksandrov, K. S., 468.Aleksandrova, L. S., 428.Alexander, F. A. D., 386.Alexander, M., 363.Alexander, R. A., 145.Alexander, S., 98.Ali, M. A., 184.Alikanov, P. P., 187.Alimarin, I. P., 412, 440.Alix, J . E., 125.Alkemade. C. T. J., 454.,41en, A. C., 78.Allam, 1Cf. G. E., 445.Allan, J. D., 369.Allard, C.. 358.Allegra, G., 142, 150, 475,Allen, B., 424.Allen, C. F. H., 260.Allen, C. R., 92.Allen, E. H., 302.Allen, F. W., 299.Allen, G., 108, 112, 113.Allen, G. F., 86.Allen, H.C., 46.Allen, K. W., 136.Allen, P. W., 103.Allen, R. H., 226.Allinger, J., 56, 63, 248.Allinger, N. L., 11, 56, 63,247, 248, 313.Allport, D. C., 235.Allpress, C. F., 339.Allred, A. L., 98.Allred, E. L., 198.483.483.503Aimenningew, A., 51.Altgelt, Von K., 105.Altman, K. I., 389.-4ltpeter, L. L., 454.Altshuller, A. P., 458.Alvarez, F. S., 198, 313.Alver, E., 495.Amai, R. L. S., 286.Amaral, J. R., 419.Ambe, K., 404.Amberger, E., 128.Ambros, D., 171.Amiard, G., 311, 323.Amin, A. A., 446, 447.Aminov, T. G., 62.Amis, E. S., 89.Amoros, J. L., 470.Amos, A, A., 312.Amphlett, C. B., 435.Anand, N., 325.Anbar, R L , 98.Anders, D. E., 202, 219.Anderson, A. A., 402.Anderson, A. G., 231.Anderson, B.M., 179.Anderson, C. D., 294.Anderson, D. G., 215.Anderson, D. H., 75.Anderson, D. M. W., 350.Anderson, E. L., 415.Anderson, E. W., 112.Anderson, G. W., 205.Anderson, H. C., 461.Anderson, H. J., 262.Anderson, J., 388.Anderson, J. H., 73.Anderson, J. R., 48.Anderson, J. S., 115, 128,Anderson, M. M., 98.Anderson, R. A., 435.Anderson, R. C., 27.Anderson, R. G., 231.Anderson, S., 160.Anderson, W. A., 98, 409.Andersson, G., 476.Andersson, S., 154.Andon, R. J. L., 10.Andreae, J. H., 94.Andreatch, A. J., 438.Andree, F., 214.Andrews, A. L., 66.Andrews, L. J., 187.Andreyeva, S. N., 478.Andrussow, K., 83.Anet, E. F. L. J., 334,Anet, F. A. L., 291.Anet, F. L., 38.153.335504 INDEX OF AUTHORS’ NAMES.Anet, R., 278.Ang, K.P., 84.Anger, V., 420, 421.Angoletta, M., 144.Angus, W. R., 63.Anibal, R. P., 414.Anliker, R., 311.Annecchiarico, F. J., 432.Anner, G., 310, 317.Anneser, E., 191, 226.Annis, J. L., 437.Anson, F. C., 442.Antal, P., 434.Anthrop, D. F., 25.Antia, N. J., 323.Antikainen, P. J., 87, 163.Antonacci, M., 447.Antonaccio, L. D., 287.Antonini, E., 92.Antoszewski, R., 417.Apar Singh, 149.Appel, H. H., 250.Appelboom, J. W. T.,Applegarth, D. A., 329.Applegate, H. E., 313.Applequist, D. E., 241.Apsimon, J. W., 255.Arai, C., 493.Arbusov, Yu. A., 229.Archambault, J ., 139.Archer, A. A. P. G., 287.Archibald, A. R., 349.Arcus, A. C., 427.Arcus, C. L., 245.Ard, W. B., 71.Arens, J. F., 205, 210.Arfin, S.M., 431.Argersinger, W. J., jun.,115.Arigoni, D., 248, 258, 310,315, 317, 318.Arison, B. H., 309.Arkell, A., 197.Armstrong, G. T., 17.Armstrong, J. J., 351.Armstrong, R. L., 52.Arndt, C., 211.Arndt, U. W., 501.Arnett, E. M., 227, 437.Arnold, C., 208, 221.Arnold, J. T., 98.Arnold, R. T., 219.Arnold, W., 96, 288, 289.Arnold, Z., 222.Arnott, S., 258.Aroney, M., 57, 65, 66.Aronsson, B., 474.Arotsky. J., 135.Arquette, G. J., 105.Arregufn, M., 198, 313.Arsenault, G. P., 429.Arsove, S., 377.Arth, G. E., 308.Arthur, H. R., 279.Arvia, A. J., 120.387.Asami, R., 347.Asbrink, S., 476.Aschaffenburg, R., 501.Asinger, F., 268.Asit Kumar Ray, 440.Aslanian, V. M., 64.Aso, K., 344.Aspinall, G. O., 346, 349.Asprey, G., 178.Asprey, L. B., 153.Asselineau, J., 217.Aszabos, A., 339.Atchley, W.A., 432.Aten, A. H. W., 137.Athavale, V. T., 427.Atherton, N. M., 72.Atkinson, G., 85.Atkinson, V. A., 248.Atoji, M., 140, 472, 475,Atwater, N. W., 307.Audrieth, L. F., 130.Auer, T., 339.Augins, P., 69.Austin, A. E., 475.Austin, T. E., 157.Auwera, A. v. d., 38.Auzins, P., 69.Avigad, G., 344.Avni, R., 454.Awe, W., 284.Axworthy, A. E., 37.Ayad, K. N., 261.Ayer, W. A., 291.Ayers, B. O., 436.Aylett, B. J., 126, 127.Aymonino, P. J., 36, 126.Aynsley, E. E., 46, 54.Ayres, C. I., 293.Ayres, G. H., 416.Baaz, M., 130.Babatschew, G. N., 434.Babcock, J. C., 312.Babin, D. R., 290, 291.Baccaredda, M., 113.Bachelor, F.W., 290, 291.Back, M. H., 27.Bacon, G. E., 116, 462,463, 465, 469.Bacon, J. S. D., 344.Bacon, R. G. R., 203.Bacskai, R., 140.Baddeley, G., 244.Baddeley, G. V., 257.Baddiley, J., 297, 351,Badea, F., 222.Bader, H., 263.Bader, R. F. W., 38, 82,Badrinas, A., 412.Baenzinger, N. C., 145,Baer, E., 220.Baer, H. H., 338.477, 481.353.181.485.Bagby, M. O., 217.Baggett, N., 272, 331.Bagli, J. F., 308.Bailar, J. C., jun., 140,Bailey, A. S., 208.Bailey, D. R., 423.Bailey, E. J., 202, 310.Bailey, G. A., 314.Bailey, P. S., 279.Bailey, R. W., 329, 344.Bailey, W. J., 200, 265.Baird, S. S., 416.Bak, B., 48.Bakeev, N. F., 109.Baker, B. R., 294, 295,Baker, D. R., 282.Baker, F. B., 141.Balaban, A. T., 272.Balakrishnan, S., 376, 378.Balandin, A.A., 202, 334.Balazs, E. A., 302.Baldwin, H. W., 92.Baldwin, M. E., 142.Baldwin, R. L., 107.Baldwin, W. H., 422.Ball, E. G., 401.Ballantine, J. A,, 276.Ballczo, H., 416.Ballhausen, C. J., 137.Ballik, E. A., 44.Ballinger, P., 172, 182.Ballio, A., 345.Ballou, C. E., 335.Balog, A., 210.Balogh, T., 429.Balsillie, A., 228.Baltes, W., 343.Barnford, ?V. R., 172.Banay, M., 337.Baney, R. H., 127.Banfield, J. E., 276.Banks, R. E., 269.Banks, W., 348.Bannister, E., 140, 157.Bannister, M. J.. 153.Banthorpe, D. V., 177.Banyard, K. E., 63.Bapat, D. S., 199.Barakat, M. Z., 444.Baranowska, J., 304.Barben, I. K., 226.Barber, H. J., 244.Barber, M. S., 214.Barbier, M., 324, 328.Barcel6, J., 412.Barclay, G.A., 486.Barcza, L., 417.Bard, A. J., 443.Bardi, R., 480.Bardoneschi, R., 317.Bark, L. S., 431, 458.Barker, G. R., 339, 340.Barker, I. R. L., 333.Barker, R., 331, 339.160.340, 342INDEX OF AUTHORS’ NAMES. 505Barker, S. A., 330, 331.Barkulis, S. S., 368.Barlow, A. J., 113.Barltrop, J. A., 254, 292.Barnard, J. A., 32.Barnes, C. S., 220.Barnes, W. H., 491, 493.Barnes, W. J., 423.Barnett, G. A., 413.Barnett, M. P., 47.Baron, G., 418.Barraclough, C. G., 144.Barrera, J., 313.Barrett, A. H., 55.Barrette, J. P., 345.Barron, B. G., 200.Barron, E. J., 220.Barrow, R. F., 26, 27, 44.Barry, W. J., 138, 204.Bartell, L. S., 46, 183.Bartels-Keith, J. R., 221,Barter, C., 63.Barth-Wehrenalp, G., 136.Bartindale, G.W. R., 490.Bartkiewicz, S. A., 452.Bartlett, M. F., 286, 288.Bartlett, N., 161.Bartlett, P. D., 167, 242.Bartley, W. J., 196.Barton, D. H. R., 170, 202,203, 205, 215, 235, 242,249, 251, 252, 255, 258,283, 307, 310, 316.271.Bartos, J., 457.Bartz, Q. R., 270.Baruchi, L., 95.Baschang, G., 342.Basco, N., 41.Basolo, F., 139, 141, 142,160, 161.Bass, A. M., 74.Bass, E. A., 452.Bass, S. J., 88.Bass, S. T., 454.Bassett, J. Y., 190.Bassette, R., 438.Bastian, B. N., 172, 244.Bastiansen, 0 ., 5 1.Basu, S., 187.Basu Roy Choudhury, R.,Bateman, H. M., 93.Bates, R. B., 252.Bates, R. G., 86.Batt, L., 33.Batterman, B. W., 466.Battersby, A. R., 282, 283,Battiste, M., 168, 232,Bauer, H.F., 160.Bauer, K., 130.Bauer, M., 243.Bauer, S. H., 56, 117, 137,449.284, 285, 288.240, 241.162.Bauer, V. J., 11, 247.Bauer, W. H., 478.Bauld, N. L., 206, 243.Bauld, W. S., 455.Baum, L. H., 74.Baumann, M., 235, 277.Baumann, U., 102.Baumgartner, R., 129.Baumgart, V. F., 433.Baumgarten, H. E., 205.Baur, R., 116.Baveen, M. A., 430.Bawn, C. E. H., 102,Baxter, C. F., 368.Bayer, R. P., 202.Baykut, F., 430.Bayliss, L. E., 389.Beachell, H. C., 105.Beal, J. L., 326.Beal, P. F., 308, 317.Beamish, F. E., 413.Bean, N. E., 131.Beaton, J. M., 316.Beattie, I. R., 127.Beaton, J. M., 203.Beattie, W. H., 106.Beaumont, D. W., 88.Beaven, G. H., 84.Becconsall, J. K., 76.Becerra, R., 308.Becher, J. H., 130.Beck, D., 345.Beck, W., 56, 142, 144,145, 150.Beck, W.H., 86.Becker, A., 432.Becker, H., 453.Becker, K. A., 481.Becker, M., 94, 101.Becke-Goering, M., 130,Beckett, A. H., 430.Bedford, A. F., 15.Bedford, R. G., 484.Beer, R. J. S., 276.Beerthuis, R. K., 305.Beevers, C. A., 463.Beevers, R. B., 112.Begun, G. M., 48.Behrens, H., 131, 143.Beinert, H., 399.Bekoe, D. A., 488.Belcher, C. B., 414.Belcher, R., 446, 449, 451,Bell, D., 354, 355.Bell, R. P., 59, 79, 80, 87,90, 91, 117, 174, 183.Bell, W. E., 25.Bellan, P. , 163.Belles, Q. C., 457.Bellis, G. E., 49.Beloff-Chain, A., 368.Belov, N. V., 463, 466,151.131, 133.461.485, 486.Belozersky, A. N., 300,Beltrame, P., 167, 174.Beltran, E.G., 435.BeMiller, J. N., 334, 348.Benaceraff, A., 153.Benck, R. F., 442.Bender, H. S., 260.Bender, M. L., 180, 183.Bendrich, A., 295, 302.Benedetti-Pichler, A. A.,Benedict, W. S., 46, 59.Benesi, H. A., 428.Bene”svQ, V., 259.Bengelsdorf, I. S., 202.Benigan, P. J., 174.Benitez, A., 295.Benkers, R., 304.Benkeser, R. A., 189, 200.Benn, M. H., 343.Bennett, J. E., 24.Bennett, M. A., 144.Ben-Shoshan, R., 339.Benson, A. A., 220.Benson, R. E., 231.Benson, S. W., 37.Bent, H. A., 47.Bentley, F. F., 115.Bentley, R., 238.Benton, F. L., 200, 219.Benz, F., 191.Benzing, E., 222.Benzinger, T. M., 24.Berbalk, H., 223.Berends, W., 304.Berezin, G. H., 314.Berg, P., 361.Berg, W. T., 12.Bergelson, L. D., 209.Berger, A., 98, 233.Berger, J.G., 222.Berggren, B., 234, 235.Bergmann, E. D., 56, 273.Bergmann, K., 61.Bergmann, W., 324.Bergsina, J., 470.Bergstrom, C. G., 312.Bergquist, P. L., 299.Berisso, B., 421.Berka, A., 418.Berka, L., 132.Berkenblit, M., 444.Berkowitz, J., 42.Berl, S., 368.Berlin, A. A., 139.Berlin, A. J., 12, 247.Berlin, Yu. A., 229.Berliner, E., 188.Bermann, M. D., 382, 386.Bermejo, F., 412.Bernal, J. D., 470, 496, 501.Bernardini, F., 124.Bernasconi, R., 258, 288.Bernauer, K., 288, 289.Berndt, W., 447.303.411506 INDEX OF AUTHORS' NAMES.Bernhauer, I<., 280, 281.Bernheim, A., 98.Bernheimer, A. W., 377.Berns, D. S., 84.Bernsee, G., 332.Bernstein, H. J., 57.Bernstein, R. B., 33.Bernstein, S., 315.Berry, K.L., 154.Berry, R. S., 192, 227.Bersanelli, G., 262.Bersohn, M., 242.Bersohn, R., 54, 67, 68.Berson, J., 167.Berson, W. B., 53.Bertaut, E. F., 477.Berti, G., 194.Bertin, D., 310, 318.Bertin, H. J., 47.Bertrand, A. J., 147.Berzins, T., 99.Bessell, C. J., 412.Bessman, M. J., 353, 355,Bestmann, H. J., 203, 204,Beukelman, T. E., 455.Beukenkamp, J., 154.Beumling, H., 236.Beutner, H., 144.Beutner, K., 145.Bevan, C. W., 178.Bevan, C. TV. L., 190.Bevan, T, H., 221.Bevenue, A., 329.Bewley, D. K., 23.Beychok, S., 19.Beycr, H., 56, 119, 197.Beyerman, H. C., 283.Beyler, R. E., 202, 409.Beyrich, T., 431.Bezman, I. I., 130.Bezzi, S., 480, 480.Bhagavantam, S., 66.Bharucha, M., 328.Bhatt, M.V., 197, 213, 248.Bhattacharyya, S. C., 218,Bhatty, M. K., 449.Bianchi, U., 107.Bible, R. H., jun., 253.Bick, I. R. C., 285.Bickel, A. F., 230.Bickel, H., 222.Bickelhaupt, F., 290, 291.Biddiscombe, D. P., 10.Biedermann, G., 87.Biellmann, J. F., 256, 313.Biemann, K., 286.Biermann, W. J., 438.Bientema, C. D., 153.Bieri, J. G., 402.Biernut, J., 102.Bietsova, N. N., 102.Bigeleisen, J., 84, 138,358.205, 213.250, 441.181, 182.Bigley, D. B., 198, 254.Bigot, J. A., 66.Billing, B. H., 260.Billingham, E. J., jun.,Billings, J. J., 113,Billings, T. J., 14.Billman, J. H., 440.Bills, J. L., 23.BindAcz, L., 210.Binder, I., 474.Binks, J. H., 193.Binks, R., 282, 283, 284,Bipp, H., 135.Birch, A. J., 237, 238, 274,Bird, C.W., 145, 246, 306.Birkeland, S. P., 203, 314.Birkhimer, C. A., 268.Birkofer, L., 264.Birnbaum, G., 61.Birr, K.-H., 15.Birss, F. W., 35.Birtlay, W. B., 52.Bishop, C. T., 328, 349,Bishop, D. H. L., 403.Bishop, E., 415, 443.Bishop, J. A., 443, 444.Bitort, 2. A,, 441.Bjellerup, L., 14.Black, E. D., 459.Blackburn, G. M., 277.Blackie, M. S., 161.Blades, A. T., 32.Blaedel, W. J., 434.BlAha, K., 283.BlAha, L., 286.Blaine, L. R., 43, 4G.Blair, M. G.. 344.Blake, D., 148.Blake, G. G., 429.Blake, P. G., 33.Blakely, C. F., 241.Blance, R. A., 27G.Blank, B., 316.Blank, F., 350.Blasius, E., 424.Blass, J. P., 369.Blasse, G., 137.Blaustein, M., 393.Blay, N. J., 120.Bleaney, B., 70, 78.Blinc, R., 116.Blinder, S.M., 60.Blix, G., 377.Block, B. P., 160.Block, S., 479.Bloemendal, H., 433.Blomgren, G. E., 73.Bloom, B. M., 312.Blow, D. M., 496.Blues, E. J., 118.Blues, E. T., 203.Bluestone, H., 247.461.288.276, 282, 288.350.Bluhm, A. L., 200.Bluhm, M. M., 496.Blum, P., 477.Blumson, N. L., 297.Bly, R. S., jun., 178.Blythe, A. R., 66.Boberg, F., 268.Bobtelsky, M., 446.Bodanszky, M., 268.Bode, H., 440.Rode, J. D., 424.Bodo, G., 398, 496.Bockman, 0. C., 249.Bodi, E. M., 449.Boedtker, H., 303, 304.Boetius, M., 451.Bohm, Z., 437.Bohme, H., 428.Boekelheide, V., 184.Boelhouwer, C. , 334.Bonnighausen, K. H., 224.Bogcrt, V. V., 312.Bogoch, S., 377, 378.Bogri, T., 291.Bogue, D. C., 435.Bohlmann, F., 211, 283.Bohm, W., 215.Boit, H.-G., 289.Bojarski, T.B., 357.Bokadia, M. M., 279.Bokii, G. B., 481.Boldano, B. A., 88.Bolingbroke, V., 385.Bollum, F. J., 354, 356.Bol'shakova, G. A., 22.Bolton, R., 190.Bolz, L. H., 473.Bond, R. P. M., 260.Rondi, A., 113.Boned, M. L., 11.Bonnelle, M. C., 47.Ronner, 0. D.. 88.Bonner, T. G., 264, 335,337, 345, 420.Bonsignore, A., 332.Booman, G. L., 426, 427.Boonstra, H. J., 210.Booth, C., 106.Booth, D. P., 468.Boothe, J. H., 228.Bootsma, H., 210.Borchert, A. E., 243.Borchert, O., 446.Bordet, C., 217.Rordwell, F. G., 176, 185.Boreck9, J., 431.Borgwardt, S., 174, 208.Bork, K. H., 310.Bornowski, H., 211.BoroviLka, M., 286.Borowitz, I. J., 242.Borrmann, D., 345.Boryta, D.A., 461.Bose, A. K., 254.Eose, A. N., 35.Bose, J . L., 278Bose, S., 285.Boskin, M. J., 239.Bossi, E., 158.Boston, J. L., 147, 159.Boswell, G. A., 203, 314.Bothner-By, A. A., 302.Botteri, A., 376.Bottini, A. T., 98.Bouman, J., 402.Bourne, E. J., 264, 329,Bourns, A. N., 178.Bousquet, W. F., 429.Bouveng, H. O., 350.Bovey, F. A., 102.Bowen, J. E., 453.Bower, V. E., 84, 86.Bowering, W. D. S., 339.Bowers, A., 308, 317.Bowers, V. A., 73, 74.Bowersox, D. F., 442.Bowman, H. E., 86.Bowyer, F., 380.Box, G. F., 458.Boyd, M. E., 473.Boyd, R. H., 110, 168.Boyd, R. N., 421.Boyer, J. H., 270.Boys, S. F., 38.Brace, R. O., 459.Brachet, J,, 260.Bracken, R. C., 48, 126.Bradbury, E. M., 108.Braddick, H.J. J., 66.Bradley, D. C., 115.Bradley, D. F., 303.Brady, A. P., 23.Brady, G. W., 80.Brand&, C.-I., 154.Bragg, W. L., 496.Brainina, €?. M., 155.Bramley, R., 57.Bramlitt, E. T., 425.Brand, J. C. D., 48, 185.Branden, C. I., 484.Brandhoff, H., 337.Brandmair, F., 127.Brandon, D. I)., jun., 167.Brandsen, C.-I., 130.Brandstatter-Kuhnert, &I.,Brandt, W. W., 412, 438.Bransford, J. W., 55.Branson, H. R., 498.Brasen, W. K., 231.Bratek, M. D., 283.Braude, E. A., 201, 270.Brauer, G., 478.Braun, G., 142, 150.Rraun, J. C., 198, 248.Braunbeck, J., 459.Braunitzer, G.9 500.BrdiCka, R., 99, 100, 102.Brearley, D., 170.Bredereck, H., 266, 267,330, 335, 344, 345, 348.422.273, 345.INDEX OF AUTHORS’ NAhlEBregman, J., 274.Brehler, B., 473, 475.Breiter, M., 100.Breitner, E., 196.Breitschwerdt, K., 97.Brenner, A., 157.Brenner, N., 435, 436.Bresler, A., 304, 361, 363.Bresler, P.I., 52.Bresler, S. E., 303.Breslow, D. S., 103, 147,Breslow, R., 229, 232, 210,Brettle, R., 217.Breuer, E., 431.Breuer, H. J., 385.Breusov, 0. N., 118.Brewer, H. W., 291.Brewer, R. F., 416.Brewster, J. H., 63, 306.Breyer, A., 434.Brian, P. W., 260.Brickwedde, F. G., 1G.Brieger, G., 282.Briggs, L. H., 255.Briggs, T., 132.Bril, J., 456.Brill, A. S., 91.Brill, R., 464.Brimacombe, J. S., 272,331, 341.Briniger, W. S., 399.Brinkmann, R. D., 123.Briske, C., 26.Rriski, J., 432.Brito, F., 87, 155.Britt, J. A., 187.Brivati, J.A., 71.Broadbent, H. S., 196.Broadhead, K. G., 441.Broadley, J . S . , 4.8 7.Brockerhoff, H., 220.Brockhouse, B. N., 470.Brockmann, H., 229.Brockmann, I<., jun., 229.Broderson, S., 48.Brodsky, W. A., 387.Broesma, S., 98.Broida, H. P., 74.Bronk, J. R., 397.Brook, A. J. W., 92.Brook, P. R., 288.Brookes, P., 268.Brooks, R. R., 434.Brooks, V. B., 376.Broome, J., 200.Brossel, J., 79.Brosset, C., 127, 156.Brossi, A., 235, 277.Brotherton, T. K., 221.Brown, B. R., 200, 279.Brown, C. J., 235.Brown, D. J., 277.Brown, D. M., 181, 220,151.331.296, 353.,507Brown, F., 380.Brown, G. B., 295.Brown, G. L., 299, 302,303.Brown, H. C., 118, 119,185, 196, 197, 198, 210,213, 224, 248.Brown, I. D., 162, 482.Brown, M.P., 49, 128.Brown, P. J., 485.Brown, R. D., 193, 195,Brown, R. F., 201.Brown, R. F. C., 290,Brown, R. M., 84.Brown, T. H., 98.Brown, W. H., 216.Browne, C. C., 8.Brownlie, G., 256.Brownstein, S., 305.Brubaker, C. H., 85.Bruce, N. F., 312.Bruice, T. C., 179, 180.Bruck, P., 246Bruckenstein, S., 87.Briickner, K., 310.Bruun, T., 279.Bryan, R. F., 491.Bryce-Smith, D., 118, 203.Bryden, J. H., 488.Buchanan, D. L., 435.Buchanan, J. G., 329, 351,Buchanan, J. &I., 353, 358.Buchanan, R. F., 434.Buchel, K. H., 273.Buchschacher, P., 318.Buchta, E., 214.Buckingham, A. D., 57, 55,Buckles, R. E., 187, 207.Bucltley, F., 61.Bucourt, R., 318.BudESinskjr, B., 448, 449.Bueche, A. M., 112.Biichel, K.H., 260.Biicher, T., 401.Biichi, G., 249, 252, 280,Buchler, A., 44.Biinau, G. V., 92.Buerger, M. J., 463, 473.Buff, F. P., 30.Buffagni, S., 139.Buhl, F., 446.Bukina, V. K., 452.Bukovska, M., 161.Bullen, C. J., 482.Bullock, E., 194.Bullst, J., 213.Bu’Lock, J. D., 211, 238,Buncel, E., 178.Bum, C. W., 108.Bunnenberg, E., 306.276.291.353.60, 62, 64, 65, 66.290, 291.271508 INDEX OF AUTHORS’ NAMES.Bunnett, J. F., 179, 189,Bunton, C. A., 167, 180,Bunyan, P. J., 193.Burawoy, A., 490.Burdge, D. N., 201.Burdon, J., 269.Burdon, R. H., 361, 364.Burg, A. B., 118, 123, 130,Burger, K., 444, 449.Burgess, E. M., 249.Burgess, J. S., 435.Burgstahler, A. W., 248,Burian, F., 248.Burkhardt, H., 321.Burn, D., 201, 306, 313.Burnell, R.H., 291.Burnett, G. M., 96.Burns, E. A., 444.Burns, E. H., 87.Burns, G., 67.Burns, J. A., jun., 126.Burns, R. P., 24, 159.Burns, W., 148.Burr, M., 229, 240.Burriel-Marti, F., 442.Burrous, M. L., 200.Burrows, B. F., 280.Burrus, C. A., 54, 58.Burstein, S., 328.Burton, K., 300.Burton, M., 90.Burton, R., 149.Buschauer, G., 326.Busev, A. I., 424, 426, 445.Bushmann, E., 473.Bussell, G. E., 226.Butcher, K. L., 23.Butler, A. F., 173.Butler, G. C., 300.Butler, J. N., 31, 39, 175.Butler, J. R., 423.Butler, W. L., 457.Butta, E., 113.BuzAs, I., 446.Buzzell, A., 19.Buzzetti, F., 316.Bykova, E. V., 171.Byr’ko, V. M., 426.Bystrom, A. M., 479.Cabbell, T. R., 434.Cabezas, M. E., 317.Cable, J.W., 467.Cade, J. A., 265.Cadenas, E., 380.Cadiot, P., 210, 213.Cady, G. H., 133, 134,Cafasso, F., 76.Caglioti, L., 258.Caglioti, V., 154.Cahill, J. A., 153.190, 226.181.131, 152.270.135.Cahn, A., 423.Cain, B. F., 255.Cainelli, G., 317.Cairncross, I. M., 346,Cairns, T. L., 210, 232.Cais, M., 234, 490.Calderazzo, F., 142, 234.Caldin, E. F., 92, 174,Caldwell, P. C., 371, 390,Caley, E. R., 417.Califano, S., 51.Callrins, E., 386.Callahan, F. M., 205.Callan, D. A., 369.Callomon, J. H., 46.Calvert, J. G., 33.Calvet, E., 16, 18, 19.Calvin, G., 148, 151.Cambie, R. C., 255.Cambour, P., 279.Cameo, M., 59.Cameron, D. W., 238.Campbell, C., 413.Campbell, G. C., 196.Campbell, R. D., 266.Campbell, T.W., 224.Campion, D. E., 14.Canady, W. J., 20.Candehore, J., 243.Canellakis, E. S., 299, 302,354, 357, 358, 361, 362,363.349.190.392.Canellakis, 2. N., 358.Canham, R. G., 86.Canny, M. J., 429.Cantero, A., 358.Cantley, M., 341.Cantoni, G. L., 298, 360.Canut, M. L., 470.Capell, L. T., 259.Carboni, R. A., 133, 206.Cardani, C., 276.Cardwell, H. M. E., 327.Carey, J. G., 191.Carey, M. J., 387.Carlisle, C. H., 496, 501.Carlon, F. E., 311, 316.Carlson, D. W., 105.Carlson, E., 246.Carlson, E. F., 70.Carlson, G. L., 115.Carlson, R. O., 55, 67.Carlstrom, A. A., 437.Carlucci, A. F., 299.Carman, R. M., 261.Carnduff, J., 209, 274.Carnell, P. J. H.. 156.Carpenter, C., 145.Carpenter, D. K.. 104, 105.Earpenter, G.B., 473, 479.Carrabune, J. A., 484.Carrano, M. J., 113.Carrick, W. L., 150.Carrington, A., 63, 68, 69,Carriuolo, J., 178, 179.Carroll, B. M., 81.Carroll, D. F., 130.Carroll, P. K., 44.Carroll, P. M., 342.Carroll, R. E., 333.Carson, A. S., 26.Cartmell, E., 49.Cartwright, P. I;. S., 442.Cartz, L., 471.Casals, P.-F., 244.Casassa, E. F., 102, 106.Case, L. C., 109, 111, 113.Caserio, F. F., jun., 167.Caserio, M. C., 173, 176,191, 240, 241.Casnati, G., 276.Cason, J.. 219.Caspar, D. L. D., 501.Cassanova, J., jun., 206,Cassie, W. B., 175, 222.Cast, J., 175.Castells, J., 309.Castellucci, N. T., 217, 239.Castillo, C. A., 367.Catanzavo, R., 368.Cattanach, J., 33.Catterall, R., 458.Cavalca, L., 480, 481.Cavalieri, L.F., 302.Cavell, E. A. S., 178.Cavill, G. W. K., 204.Cavina, G., 432.Ceausescu, D., 444.Cejka, J., 153.Centola, D. D., 224.Cereghetti, M., 318.Cerfontain, H., 185.Ceron, P., 122.cerny, J. V., 265, 315, 316.Cerry, L. C., 103.Cesca, S., 150.Chabrier, A., 65.Chagas, C., 373.Chailakhien, L. M., 383.Chain, E. B., 368.Chakravarti, D., 288.Chakravarti, K. K., 218.Chakravarti, R. N., 288.Chalk, A. J., 117.Challoner, A. R., 12.Chalmers, R. A., 442.Chamberlain, J. T., 490.Chamberland, B. L., 132.Chambers, K., 279.Chambers, R. D., 121, 128.Chan, S. C., 188.Chan, W. R., 255.Chance, B., 91, 397, 406,Chandrasekhar, S., 463.Chandross, E. A., 167, 248.Chang, H. S., 180.75, 81, 159.243.407, 409INDEX OF AUTHORS’ NAMES.509Chang, M. S., 130.Chang, Shih., 192.Chantry, G. W., 51, 65.Chao, G. Y., 136.Chao, S. Y., 484.Chao-Tung Chen, 202.Chapman, A. C., 130.Chapman, D., 220.Chapman, D. D., 261.Chapman, F. W., jun.,Chapman, N. B., 174, 176,Chapman, 0. L., 230.Cherezifiski, M., 422.Chargaff, E., 298, 300, 377,Charles, S. W., 227.Charlson, A. J., 332.Charney, E., 65.Charney, W., 325.Chatt, J., 56, 139, 143, 145,151, 153, 157.Chatterjee, A., 285, 288.Chauveau, F., 155.Chayen, R., 429.Cheeseman, G. H., 117.Cheeseman, G. W. H., 273.Cheikowski, A., 60.Chemerda, J. M., 309, 314.Chen, D., 179.Chen, J. H., 95.Cheng, F. W., 450.Cheng, W., 47, 64.Cheong, L., 295.Chernick, C. L., 135.Chernikhov, Y.A., 457.Chernin, R., 440.Chernyshov, E. A., 185.Chesick, J. P., 36.Chesnut, D. B., 75, 81.Chesnutt, J. T., 457.Chesterfield, J . H., 272.Chetk.in, M. V., 65.Chia-Chen Chu Kang, 456.Chialda, I., 448, 450.Chiang, R., 110.Chibrikin, V. M., 77.Chieko Furuki, 414.Chien, J. C. W., 147.Child, H. R., 472.Childs, C. E., 438.Chin, D., 129, 133.Chinai, S. N., 104.Chini, P., 143.Chinoporos, E., 418.Chipman, D., 240.Chipperfield, J. R., 128.Chisholm, M. J., 217.Chissick, S. S., 282.Chiswell, B., 161.Chiurdoghu, G., 247, 248,Chiusoli, G. P., 213.Chmielewska, I., 409.Chmutov, K. V., 428.459.178.378.251.Chodkiewicz, W., 210.Chopra, N. W., 250.Choudhuri, S. N., 253.Chouteau, J., 218.Chovin, P., 16.Chow, S.W., 249.Chowdhury, M., 187.Chow Wei-Zan, 251.Christ, C. L., 478, 486.Christensen, B. G.. 309.Christensen, H. N., 380,Christensen, J. E., 336.Christenson, R. M., 225.Christian, J. E., 429.Christiansen, J. A., 93.Christman, D., 271.Christman, D. R., 168.Chu, P., 340.Chukreev, N. Ya., 118.Chundela, B., 438.Chung, C. W., 363, 364,Chupka, W. A., 42.Church, C. H., 44.Church, R. F., 254.Ciampolini, M., 23, 56, 138,Ciavatta, L., 154.Cieplinski, E., 436.Ciferri, A., 111.Ciganek, E., 171, 199, 243.Cingolani, E., 432.Cini, R., 142, 161.Ciofalo, R., 138.Cioranescu, E., 222.Citron, M., 427.Ciiek, J., 100.Clair, E. G., 100.Clancy, M. J., 344.Clar, E., 184, 228.Clark, D. E., 235.Clark, F. S., 189.Clark, H.C., 76, 121, 128.Clark, H. W., 398.Clark, J. R., 486.Clark, R. J., 268.Clark, R. M., 421.Clark, R. O., 452.Clark, V. M., 285, 298, 409,Clarke, E. G. C., 422.Clarke, G. A., 173Clarke, K., 176.Clarke, P. H., 395.Clarke, R. L., 307.Clark-Lewis, J. W., 279.Clastre, J ., 490. IClaydon, A. P., 22.Clayton, L., 55.Cleverley, B., 459.Cley, J., 210.Cline, C. F., 127, 474.Cline, R. E., 295.Clogston, A. M., 69.Chow, Y.-L., 255.393.366.161.493.Close, R. A., 417, 447.Closs, G. L., 223, 230, 239.Closs, L. E., 223, 230, 239.Clough, S., 76.Clunie, J. C., 91.Clunie, J. S., 252, 493.Coates, F. H., 27.Coates, G. E., 115, 148,Coates, J. H., 302.Coates, V. J., 436.Coats, N. A., 269.Cobble, J. W., 22, 23.Cochran, E.L., 73, 74.Cochran, W., 463, 470.Cocker, W., 249, 250,Cockerill, D. A., 275.Cocozza, E. P., 424.Codner, R. C., 238.Coe, J. P., 171.Cormos, D., 443.Coffield, T. H., 143, 148.Coffman, D. D., 133, 206,Cogan, E., 426.Cohen, A., 184, 228.Cohen, D., 296.Cohen, G. N., 391.Cohen, H. J., 154.Cohen, I. R., 458.Cohen, M. H., 67.Cohen, M. M., 446.Cohen, M. S., 128.Cohen, S . S., 357, 358.Cohen, T., 491.Cohn, H., 189.Cohn, M., 394.Cohn, W. E., 296, 299.Coing-Boyat, J., 479.Colapietro, J., 186.Colbran, R. L., 338.Colburn, C. B., 128, 129.Cole, R. H., 58, 62.Cole, T., 71, 72, 75.Coleman, B. D., 110.Coller, B. A. W., 193.Colli, L., 143.Collins, A. M., 326.Collins, C. H., 170, 173.Collins, D. J., 314.Collins, F.D., 220.Collins, R. J., 79.Collman, J. P., 138.Collotti, G., 479.Colomina, M., 11.Colonge, J., 213.Colpa-Boonstra, J. P.,Colton, E., 124.Colton, R., 62, 148, 158.Comb, D. G., 298.Comyns, A. E., 153.Cone, N. J., 288.Conia, J.-M., 239, 248.Conley, R. T., 223.151.251, 264.207, 208, 213.408510 INDEX OF AUTHORS, NAMES.Conner, A. Z., 439.Connolly, J. D., 250.Connor, J., 454.Conrad, H., 407.Conrick, R. E., 95, 159.Conroy, H., 277, 288, 292,Contag, B., 477.Conti, L., 479.Conway, B. E., 103.Conway, E. J., 381, 382,Cook, C. M., 95.Cook, T. M., 400.Cook, W. H., 297.Cooke, W. D., 454.Cooke, W. E., 413.Cookson, K. C., 145, 166,Coolidge, T. B., 447.Coop, I. E., 59.Cooper, A. D., 439.Cooper, C., 397, 406.Cooper, F.P., 328, 349.Cooper, G. D., 127.Cooper, M. J., 485.Cooper, O., 401.Cooper, W. J., 22.Cooperstein, I. L., 392.Coops, J., 9.Cope, A. C., 171, 199, 243,244, 248, 273.Copenhafer, D. T., 83.Coppola, J., 493.Corbett, J. D., 132.Corbin, E. A., 429.Corbridge, D. E. C., 479.Cordes, E., 298, 302.Corey, E. J., 206, 243, 258,306, 315, 325.Corey, R. B., 166, 498.Corliss, L., 156.Corliss, L. M., 466.Cormack. J. F., 226.Corney, E. J., 249.Cornforth, J. W., 215, 216,Cornforth, R. H., 216, 223.Corradini, P., 108, 142,Corse, J., 437, 438.Corsini, A., 441.Corwin, A. H., 263.Cosgrove, J. D., 451.Costain, C. C., 48, 55.Cotton, F. A., 15, 23, 56,62, 139, 140, 143, 146,160, 161, 234.Cotton, R., 144.Cotton, T.M., 425.Coulson, C. A., 184, 232.Courtois, J. E., 337.Cousin, B., 451.Cousins, F. B., 456.Coverdale, A. K., 172.Covington, A. I<., S6.305.383, 385, 387, 388.246, 306.267, 305, 324, 342.143, 150, 475, 483.Cowan, H. D., 141.Cowan, J. C., 202, 219.Cowdell, R. T., 154.Cowley, A. H., 123.Cox, E. G., 486.Cox, J. D., 10, 12, 13.Cox, J. S. G., 309.Cox, K. A,, 302.Coxon, B., 342.Coxon, R. V., 367.Coyle, T. D., 121.Craig, D. N., 79.Craig, D. P., 49, 183.Cram, D. J., 150.Cramer, F., 215.Cramer, F. D., 296.Cramp, W. A., 219.Crane, E. E., 388.Crane, F. E., jun., 439.Crane, F. L., 398, 403,Craven, B. M., 277, 486.Crawford, B., 51, 52, 92.Creese, R., 386.Creeth, J. M., 86.Creighton, A.M., 199, 201,Creitz, E. E., 455.Cremer, S., 244.Crestfield, A. M., 299.Crick, F. H. C., 496, 501.Criegee, R., 241.Crighton, J., 121.Crissman, J. &I., 112.Cristiani, G. F., 262.Cristol, S. J., 168, 158,Critchfield, F. E., 417, 458.Crocket, D. S., 135.Croft, R. C., 125.Crombie, L., 280.Cromer, D. T., 474, 478,Croom, I., 349.Cropper, F. R., 410.Crosbie, G. W., 353.Cross, A. D., 260, 325.Cross, B. E., 250, 251, 256,Crossland, I., 428.Crouch, D. E., 157.Crowder, J. R., 289.Crowder, M. M., 464, 490.Crowe, B. F., 209.Crowlie, J. H., 223.Cruickshank, D. J., 129.Cruickshank, D. W. J.,Crumpton, C. W., 367.Crutchfield, M. M., 88.Crutchley, D. J., 276.Crute, M. B., 491.Csik, J., 445.Culbertson, T. P., 264.Cullen, W.R., 132.Cullis, A. F., 495.404.336.245.485.277.465, 469, 487.Cullum, D. C., 444, 456.Culvenor, C. C. J., 261.Cummins, J, T., 370, 376.Cumper, C. W- N., 55.Cunho Lima, L. C. O., 432.Cunningham, B. B., 153.Cunningham, W. L., 348.CuprovA, V., 161.Curl, R. F., 48, 55.Curphey, T. J., 152, 233.Curran, P., 393.Curran, P. I?., 380.Current, J. H., 41.Currie, D. J., 86.Curry, A. S., 412, 415.Curry, N. A., 116, 465,Curtis, A. J., 57.Curtis, D. R., 376.Curtis, E. J. C., 336, 337.Cusworth, D. C., 369.CvetanoviC, R. J., 40.Cyvin, S. J., 51.Czerlinski, G., 94.Daalder, A., 445.Uahne, W., 155.Daeniker, H. U., 218.Dassler, C., 337.Dahl, L. F., 475.Dahlkn, J., 235.Dahlgren, G., 86.Dahlgren, G., jun., 182.Dainton, F.S., 62, 76,Dainty, J., 380.d’Alelio, G. F., 264.Dallacker, F.. 216.Dallam, R. D., 409.Dal Nogare, S., 437.Dalton, L. K., 218.Dalziel, J., 158.Damany-Astoin, N., 47.D’Amato, V., 262.Damiana, A. M., 247.Dancy. J., 176.Danford, M. D., 133.Danieli, N., 274, 312.Danielli, J. F., 382.Daniels, R., 175, 237, 269.Dannley, R. L., 421.Danon, J., 430.Danowski, T. S., 385.Danti, A., 43.Danusso, F., 105, 110, 112.Danyluk, I. S., 85.da Re, P., 278, 279.Darling, S. D., 200.Darlow, S. F., 487.Darnell, A. J., 25.Dart, M. C., 196.Daruwalla, E. H., 347.Das, T. P., 54, 67.Dasent, W. E., 137, 145.Da Settimo, A., 194.Das Gupta, P. C., 349.469.117Dasher, J., 443.Datta, S. I<., 473.Dauben, C.H., 469.Dauben, H. J., jun., 27,166.Dauben. W. G., 8, 203,250, 306, 314, 322.Daukshas, V. K., 10.Daum, G., 264.Daun, H., 377.Daunicht, H., 132.Dave, L. A., 233.David, D. J., 458, 459.Davidek, J., 429.I>avidson, J . M., 124, 281.Davidson, J. N., 87, 353,354, 355, 359.Davidson, N., 96.Davidson, N. R., 75.Davidson, T. A., 235.Davie, A. W., 258.Uavies, A. G., 16G.Davies, D. I., 178.Davies, J. B., 214.Davies, J. W., 287.Davies, M., 57, G l .Davies, R. E., 386, 388.Davies, R. O., 94.Davies, W., 261.Davies, W. A. RI., 280.Davis, A. G., 216.Davis, B. D., 237, 395.Davis, B. R., 255.Davis, D. G., 442.Davis, D. K., 435.Davis, D. R., 495.Davis, €7. F., 299, 433.Davis, G. T., 179.Davis, J. C., 57.Davis, M., 308.Davis, N.AT., 84.Davis, S. G., 25.Davis, W. I?,, 425, 426.Davis, W. J., 264.Davison, A., 152.Davison, P. F., 302.Davson, H., 369.Dawes, J. W., 163.Dawson, J. P., 12, 14.Dawson, L. R., 85.Dawson, 13. b1. C., 221,Day, A. C., 235, 277.Day, M. C., 88.De, A. K., 425, 436.de Acha, A., 470.Dean, F. &I., 258.Dean, J. A., 424, 425, 454.Deane, A. M., 459.De Boer, F., 75.Debras-Guedon, J ., 455.de Brouckhre, L., 57.Debuch, H., 220.Debye, P., 91, 106.Decker, 13. F., 453.Decora, .I. IV., 436.393.INDEX OF AUTHORS’ NAMEDecroly, P., 88.Defalco, A,, 368.De Feo, R. J., 223.Deffner, G. G. J., 369.Degeilh, R., 491.de Groot, M. S., 78, 95.Degucki, Y., 72.de Haas, G. H., 220.de Hemptinne, M., 48.de Heus, J.G., 432.Dehm, Ill. C., 147.Dejak, C., 90.de Kleuver, G. J., 432.Deklier, C. A., 260.Dekker, H., 9.De Kock, €2. J., 242.de Kowalewski, D. G., 55.Delaliay, P., 99, 100, 101.de la Mare, P. B. D., 136,172, 187, 188, 193, 195,276.de Lamirande, G., 358.Delbecq, C. J., 70.Delfs, D., 264.Delliaye, A., 189.de Liefde Meijer, H. J.,Dell, J. C., 452.ilellweg, H., 280, 281.Delobelle, J., 253.Delpierrc, G. R., 263.Dcl Re, G., 56.De Maeyer, L., 80, 92, 94,Demain, A. L., 260.De Marco, J . J., 466.De Maria, G., 24.De Mayo, P., 235, 242, 248.Demoen. P., 453.Denbigh, K. G., 91, 93.den Boef, G., 445.Dench, W. A., 18.de Neui, R. J., 46.Denney, D. B., 202, 313,Denney, D. Z., 202.Dennis, W. H., 387.Deno, N.C., 166.Denot, E., 308, 317.Dent, C. E., 369.De Puy, C. H., 32, 172,203, 245, 246.Derbes, M. T., 117.Dersin, B., 135.Descamps, Rf., 251.Desnuelle, P., 220.Dessy, R. E., 118, 203.Desty, D. I<., 435.Detoni, S., 48.Deuel, H., 346, 350.Deul, D., 402.Deul, D. H., 375.Deulofeu, V., 287, 328.Deutsch, J. L., 27.de Verclier, C. €I., 429.Ucvlin, J. I>., 18, 51, 120.149.95.239, 450.511Devliti, T. M., 406.cle Vries, L., 168, 223, 241,244, 24G.Dewar, M. J. S., 183, 184,185, 195, 275, 281, 282.de Wet, J. F., 433.de Wet, W. J., 436.Dey, A. K., 430.Deyrup, I., 386.Dhar, M. L., 221, 325.Dhar, M. M., 325.Diamond, I., 387.Diamond, K., 471.Diamond, R. M., 115.Diaper, D. G. M., 200.Dibeler, V. H., 27.Dick, R.D., 48.Dicker, D. W., 274.Dickcrson, K. E., 495.Dickey, F. P., 46.Dickie, J. P., 275.Diclinian, J., 78.Didchenko, R., 125.Uidier, H.-J., 428.Diebler, H., 04.Diehl, H., 447.Diehl, H. W., 340.Dieke, G. €I., 44.Diesen, R. W., 28.Uietrich, 31. R., 207.Dietrich, W. C., 445.Dietz, R., 281.Diliareva, L. ILI., 481.Dills, C. B., 167.Dills, D. II., 41.Di Maio, G., 325.Dimant, E., 337.Dihlarzio, E. A., 112.Uimi-oth, I<., 260, 272.Dinerstein, I<. A., 436.Dingman, W., 368.Dinneen, G. U., 436.Uinnin, J . I., 444, 455.Dintzis, Ii. RI., 496.Dion, H. W., 270.Diringer, R., 304, 361.Dirks, J . E., 205.Dirscherl, A., 453.Dische, Z., 332.Dischler, U., 95.Distler, J. J., 351.Dittmer, J. C., 221.Dix, P.A., 271.Dixon, J. A., 200,Dixon, J. P., 452.Dixon, R. N., 44, 46.Dixon, P. S., 151.Djerassi, C., 63, 248, 250,251, 255, 258, 287, 305,306, 311.Dmuchowrski, B. L., 333.Dobkina, B. hf., 457.Dobson, J. V., 86.Doctor, B. P., 298.Dodd, G. AT., 276.Eodd, K. E., 46, 54512 INDEX OF AUTHORS’ NAMES.Dodge, R. P., 149.Doeg, K. A., 404.Doeheard, T., 248.Doll, G., 140.Dopke, W., 289.Dorfel, H., 347.Doerffel, K., 454.Doering, W. von E., 38,Doerr, I. L., 295.Doetsch, V., 135.Doggart, J. R., 203.Dogonadse, R. R., 99.Doi, J. T., 173.Dolby, L. J., 288.Dolder, F., 255.Dole, M., 110.DolejS, L., 251, 252.Dolgaya, M. E., 185.Dolliver, M. A., 9.Domange, L., 153, 478.Donaldson, K. O., 402.Donaldson, M.M., 168,Donath, W. E., 12.Donnay, G., 466, 486.Donnay, J. D. H., 466.Donohue, J., 465, 472.Donovan, T. M., 13, 16.Dorain, P. B., 70.Dorazil, L., 447.Dorfman, L., 450.Dorfman, R, I., 314, 325.Dornberger-Schiff, K. , 466.Dornow, A., 267.Dostal, K., 131.Doty, P., 302, 303, 304,Douglas, C. M., 131.Douglas, I. B., 223.Douglas, T., 340.Douslin, D. R., 12, 14.Dousmanis, G. C., 58.Douthit, R. C., 117.Dove, M. F. A., 128.Dowling, J. M. , 48.Down, J. L., 76, 117.Downing, D. T., 220.Downman, C. B. B., 384.Downs, A. J., 126.Doyle, F. P., 261.Doyle, J. R., 145.Doyle, L. C., 40.Doyle, W. T., 70, 117.Drago, R. S., 129, 139.Drake, J. E., 154.Dravnieks, F., 75, 81.Dreeskamp, H., 90.Dreger, L. H., 11, 26, 247.Dreiding, A.S., 230.Dresdner, R. D., 128, 207.Dressler, K., 43.Drkze, A., 429.Drinkard, W. C., 160.Drowart, J., 24.Druey, J., 218, 342, 343.232, 240.245.356.Drummond, D. W., 347.Dryden, J. S., 61.Drysdale, J. J., 207.Dubeck, M., 185.Dubois, J. T., 34.Dubourg, J., 335.Dubsk?, H. E., 437.du Chaffaut, J. A., 240.Duck, E. W., 125.Dudek, G. O., 89.Duecker, H. C., 79.Duffey, D. C., 175.Duffield, J. J., 436.Duffy, J. A., 180.Dufour, R. F., 445.Duke, J. F., 427.Dulbecco, R., 296.Dulova, V. G., 230.Dunbar, R. E., 421, 422.Dumbaugh, W. H., jun.,Duncan, A. B. F., 54.Duncanson, L. A., 140.Dunford, H. D., 80.Dunham, E. T., 389.Dunitz, J. D., 115, 137,149, 162, 482, 491.Dunlop, A. P., 264.Dunn, D. B., 299, 300.Dunn, M.S., 205, 431.Dunn, P., 154.Dunn, T. M., 139.Dunstan, I., 120.Dupont, J. A., 120.Duprez, G., 347.Dupuis, T., 127.DurAn, A,, 283.Durbin, R. P., 380.Durham, E. T., 392.Duschinsky, R. , 294.Duswalt, A. A., 438.Dusza, J. P., 324.Dutch, P. H., 437.Dutta, P. C., 253.Duttagupta, P. C., 278.Dutton, G. G. S., 339, 349.Dutton, W., 121.Duval, C., 411, 460.Duvie. R. A.. 44.20.Duwell, E. J:, 485.Duynstee, E. F. J., 89,173.Dvolaitzky, M., 312, 315.Dwyer, F. P., 142.D’yakanov, I. R., 240.Dye, J. L., 85, 117.Dyer, F. F., 425.Dyer, R. F., 463.Dyrssen, D., 163.Dytham, R. A., 218.Dzegamovskii, V. P., 153.Eaborn, C., 127, 185, 186,Earl, N. J., 276.Earley, J. E., 141.188, 189.Earley, J. V., 449.Earwicker, G.A., 161.Eastman, D. P., 46, 47,Eastman, R. H., 202, 242.Eaton, D. R., 47.Eaton, P., 246.Ebel, H. F., 227.Eberhardt, M., 167.Eberhardt, W. H., 47, 64.Eberlin, E. C., 112.Ebert, M., 156.Ebisuzaki, K., 357.Ebsworth, E. A. V., 126.Eccles, J. C., 373, 376.Eckart, D. W., 474.Eckel, R. E., 385.Eckman, J. R., 18.Eden, M., 86.Eder, K., 451.Edison, D. H., 177.Edlkn, B., 27.Edmison, M. T., 193, 227,Edmonds, M., 361, 364.Edmundson, A., 499.Edward, J. T., 250.Edwards, A. J., 156, 157.Edwards, C., 382, 392.Edwards, J., 312.Edwards, J. D., 175.Edwards, J . O., 88, 118,Edwards, J. T., 180.Edwards, J. W., 412.Edwards, 0. E., 239, 254,Edwards, P. N., 288.Edwards, T. P., 284.Eeles, W. T., 293, 493.Effenberger, F., 267.Egami, F., 301.Eggerer, H., 215.Eggers, D.F., 52, 55.Eggers, J. H., 446.Eggersten, F. T., 437.Eggerton, F. V., 343.Eggleston, L. V., 369, 370,Eglinton, G., 209, 224,Ehrenpreis, S., 373.Ehrhart, W. R., 221.Ehrlich, H. W., 463.Ehrlich, H. W. W., 491.Ehrlich, P., 108, 139, 155.Eichhorn, E. L., 491, 494.Eidelberg, E., 373.Eidinoff, M. L., 295.Eigen, M., 80, 92, 93, 94,Eigner, J., 302, 356.Eisch, J., 115.Eisenberg, H., 303.Eisenbraun, E. J., 63, 251.Eisenhauer, C . M., 470.52.304.197, 222.255.386, 387.274, 305.95, 194INDEX O F AUTHORS’ NA4MES. 613Eisenhnth, W., 235.Eisfeld, W., 308.Eisinger, J. T., 55.Eider, M., 312.Ekstrom, B., 224.Elbeih, I. I. M., 416, 430.Elbert, W. C., 420.Elderfield, R.C., 326.Eliel, E. L., 8, 199, 212,Eliott, J. J., 183.El Khadeni, IT., 344.Elks, J., 202, 307, 309, 310.Ellefson, R. D., 200.Ellert, H., 448.Ellingboe, J., 447.Ellington, P. S., 306.Elliot, W. B., 408.Elliott, A., 108.Elliott, K. A. C., 383, 386,Elliott, M. C., 426, 427.Elliott, N., 156, 466.Ellis, G. P., 343.Ellis, I. A., 126,Ellison, F. O., 54.Elming, N., 260.Elphimofl-Felkin, I., 314.El Raheem, A. A. A., 446.E l Sawi, M. M., 335.Elsbach, P., 386.El-Shafci, 2. M., 344.Elson, R. E., 476.Elving, P. J., 411.Emelttus, H. J., 115, 119,134, 135, 233.Emerson, D. W., 167.Emerson, M. T., 98.Emerson, 0. H., 258.Emerson, R., 96.Emslie, A. G., 44.Endrbi-Havas, A., 440.Engel, I,. L., 455.Engelbrecht, A., 54.Engelhardt, V.&4., 133,134, 206, 207, 230.Engels, S., 132.England, D. C.. 207.Enns, L. H., 385.Enomoto, S., 48.Enrione, M., 363.Entner, N., 359.Entschel, R., 214, 215.Ephrati-Elizur, E., 300.Epsztein, R., 210.Ercoli, R., 142, 234.Erdey, L., 433, 446, 463,Erdtman, A., 252.Erdtman, H., 255.Eremenko, V. Y., 424.Erickson, R. E., 187.Erley, D. S., 226.Erne, F., 453.Ernest, I., 286.Erpenbeck, J. J., 104.227.387.461.REP.-VOL. LVIIErtel, D., 155.Eschenmoser, A., 245.Eskin, V. E., 105.Espenson, J. H., 82.Estin, A., 61.Ettinger, R., 79.Ettre, L. S., 435, 436.Evans, A. G., 83.Evans, n. F., 233.Evans, F. W., 10, 11.Evans, H. T., 479.Evans, H. T., jun., 153..Evans, J. C., 48.Evans, J.&I., 345.Evans, M. G., 82.Everett, G. A., 295.Evers, E. C., 84, 126.Ewers, J. W., 123.Exley, D., 454..Eyring, H., 31, 42, 93, 98.Ezhov, Y. S., 131.Faber, M. P., 85.Fabra, J., 263.Fabri, G., 82.Fabricand, R. P., 55, 67.Fange, R., 393.Fagerlund, U. IT. M., 324.Fagerson, I. S., 435.Fahrenholts, P. R., 177.Faigle, H., 237.Fairbrother, D. M., 10, 14.Fairbrother, F., 125.Fairfull, A. E. S., 269.FajkoS, J., 196, 306, 311,Fales, H. M., 289.Falkenhagen, H., 90.Falkner, P. R., 178.Fallon, K. J., 45.Falqui, M. T., 123.Faltaous, M. S., 283.Fanale, D. F., 452.Fanelli, A. K., 92.Fang, hf. S., 183.Fanguin, R., 65.Fano, L., 49.Faris, J. P., 434.Farmer, R. C., 190.Farnum, D. C., 229, 240,Farrow, G., 108, 112.Farskj., R., 453.Fassel, V.A., 454.Faulhaber, G., 144.Fauth, M. I., 461.Fava, A., 167.Fava, G., 480, 481.F a n e , J., 418.Fawcett, F. S., 126, 133,Fazekas, J. F., 385.Fechtig, B., 222, 326.Fedeli, E., 431.Feder, H. M., 17.Federovskayn, E. A . , 147.313, 314.266, 268.206.Fehkr, F., 126.Fehlner, F. P., 123.Feig, G., 202.Feinland, R., 438.Feld, M., 193.Feldberg, W., 372.Feldman, C., 414.Feldman, D., 398.Felicetta, V. F., 330.Fell, G. S., 228.Feltham, R. D., 145.lceigl, F., 419, 421.Fenetti, L. D., 238.Fenn, W. 0.. 381.Fenton, A. J., jun., 445.Fergusson, J. E., 158.Fernandez, L. P., 19.Fernhdez-Bolaiios, J.,Fernando, Q., 194, 424.Ferretti, M., 429.Ferrin, I;. J., 421, 422.Ferrini, P.G., 258, 310.Ferris, A. F., 196.Ferry, J. D., 112.Fessenden, J. S., 219.Fessenden, R. W., 72, 77.Fetizon, M., 253.Fetterman, P. L., 433.Feyer, G., 70.Fiecchi, A., 431.Ficld, G. F., 252.Fields, E . I<., 228.Fields, T. L., 228.Fieser, L. F., 305, 309, 325,Fieser, M., 305, 325.Figgis, B. N., 62.Figueiredes, E. A., 357.Filbey, A. H., 151.Filippova, N. A., 425.Fill, M. A., 442.Finan, P. A., 346.Finar, I. L., 2G5.Finch, A., 132.Finch, J. T., 501.Finch, N., 279, 306.Finckenor, L., 312.Fine, D. A., 159.Fink, K., 295.Fink, R. M., 295.Finkbeiner, H. L., 206.Finkelstein, M., 206.Finnegan, R. A., 255.Finnie, L. N., 473.Finsen, P. O., 163.Finston, H. L., 440.Firestone, R., 314.Firsching, F. H., 442.Fischer, A., 88, 262.Fischer, A.I<., 15, 155.Fischer, E.. 333.Fischer, E. O., 142, 144,145, 146, 147, 149, 150,152, 233, 234.337.3%.Fischer, F. G., 325, 347.T514Fischer, G., 420.Fischer, G. A., 358.Fischer, H., 213.Fischer, H. 0. L., 338.Fischer, J., 133, 418.Fischer, R. B., 441.Fischer, R. D., 147, 150.Fischerovh-Bergerovh, V.,Fischl, J., 426.Fischmann, E., 490.Fish, R. W., 166, 224.Fisher, G. S., 198, 248.Fisher, P. J., 162.Fisher, R. B., 380.Fishman, G., 253.Fishman, J., 311.Fishman, M. M., 348.Fishman, W. H., 332.Fitzwater, D. R., 483.Fixman, M., 103.Flahaut, J., 478.Flaig, W., 236.Flaks, J. G., 357, 358.Flaschka, H. A., 443.Flautt, T. J., 197.Fleckenstein, A,, 389.Fleckenstein, L.J., 199.Fleischer, E. B., 139.Fleischer, H., 184.Fleischer, S., 403.Fleming, I. D., 348.Fleming, J. E., 153.FleS, D., 196.Fletcher, G. A., 309.Fletcher, H. G., 294.Fletcher, H. G., jun., 340.Fletcher, M. H., 458.Fletcher, W. H., 47.Fleury, P., 337.Flitcroft, N., 125.Flock, F. H., 236.Flory, P. J., 102, 110, 111.Floss, H. G., 282.Flournoy, J. M., 74.Flowers, M. C., 37, 38.Flowers, R. H., 85.Fluck, E., 130.Foell, T., 315.Foerster, D. R., 129.Forster, Th., 90, 97.Folch, J., 377, 378, 379.Folkers, K., 403.Foltz, R. L., 283.Foner, S. N., 73, 74.Fonken, G. J., 322.Fontanella, L., 262.Fontell, K., 217.Forbes, E. J., 230.Forchielli, E., 314.Fornaini, G., 332.Forrest, W. W., 19.Forrester, F., 216.Forrester, J.S., 415, 458.Forster, W. A., 447.Forstner, J. A., 130.418.DEX OF AUTHORS’ NAMES.Fortune, L. R., 110.Foss, O., 133.Foss, 0. P., 415.Foster, A. B., 272, 330,331, 341, 343.Foster, A. G., 441.Foster, G., 203.Foster, J. M., 38.Fowell, P. A., 22.Fowler, L. R., 290.Fowles, G. W. A., 49, 154,Fox, J. J., 260, 294, 295.Fraenkel, G., 194.Fraenkel, G. K., 68, 73,Fraga, F., 283.Frampton, V. L., 279.Franc, J., 433.FrancetiC, D., 313.Francis, R., 139.Franck, B., 283.Francombe, M. H., 468.Franconi, C., 98, 194.Frank, F. C . , 109, 484.Frank, P. J., 75.Frankel, M., 223.Frankel, G., 98.Frankel, S., 368.Franklin, J. L., 74, 93.Franklin, R., 501.Franzen, F., 222.Franzen, V., 222.Fraser, F. M., 9.Fraser, R.T. M., 141, 145.Frasson, E., 161, 163, 480,Frauenglass, E., 246.Fray, G. I., 216.Frazer, A. C., 380.Frazer, B. C., 467.Frazier, H. S., 385, 387.Frazer, R. D. B., 108.Fredrickson, D. S.. 380.Freedman, A. D., 368.Freegarde, M., 424.Freeman, A. J., 466.Freeman, D. J., 367.Freeman, J. P., 129.Freeman, P. I., 108.Freeman, R., 81.Freeman, R. C . , 207.Freiberg, L. A., 11, 247.Freifelder, M., 196.Freiser, H., 423.Freitag, W. O., 126.French, C. M., 85, 281.French, D., 346, 348, 492.French, J. C., 270.French, W. N., 291.Freni, M., 144, 158.Frkrejacque, M., 327.Fresco, J. R., 304.Freudenberg, K., 237, 260.Freundt, K. J., 389.156.FOX, rr. G.. 113.92.490.Freure, R. J., 216.Frey, H. M., 31, 37, 38, 39,175, 222, 239.Frey, J., 122.Frey, M.B., 26.Freyer, W., 143.Friberg, S., 476.Fridrichsons, J., 289, 294,Fried, J., 268.Fried, J . H., 174, 207, 308.Fried, S., 158.Friedkin, M., 358.Friedland, S. S., 305.Friedlina, R. K., 155.Friedman, H. L., 90.Friedman, L., 42, 208,Friedman, S., 308.Friedrich, I%’., 280, 281.Fries, R. J., 475.Frieser, R. G., 421.Frisch, M. A., 11, 16, 247.Frisque, A. J., 453.Fritz, G., 126, 127.Fritz, H. P., 146, 149, 152,Fritz, J. S., 434, 443, 448.Frohlich, H., 58.Frohlich, W., 145.Froemsdorf, D. H., 32, 172.Frohardt, R. P., 270.Frohwein, Y. Z., 339.Fronaeus, S., 82.Frow, F. R., 12.Fry, A., 167.Fuchikami, T., 476.Fuchs, O., 200.Fuhrman, F. A., 380.Fujimoto, M., 74, 434.Fujisawa, T., 270.Fujise, S., 280.Fujishiro, R., 66.Fujita, E., 285.Fujita, H., 107.Fujita, T., 332.Fujita, Y., 264.Fukui, K., 184.Fukushima, S., 455.Fukunaga, T., 197, 199.Fuller, A.T., 268.Fuller, W., 465.Fulthorpe, A. J., 3’76.Funk, H., 158.Fuoss, R. M., 84.Furberg, S., 494, 495.Furlong, N. B., 354.Furman, F. M., 225.Furman, N. H., 445.Furth, J., 363.Furukawa, J.. 108.Furumaya, T., 112.Fynn, G. H., 402.Gabriel, O., 329.Gadecki, F. A., 166.494.221, 222.233INDEX OF AUTHORS’ NAMES.George, J. W., 133.George, T., 251, 287.George, W. O., 125, 221.Georgian, V., 55, 315.Gerard, R. W., 382, 391.Gere, E. O., 70.Gerecke, M., 235, 277.Gergely, J., 302.Gerhardt, W., 159.Gerischer, H., 99, 100.Gerlach, E., 389.Gerlach, K., 143.Germain, G., 488.Gerrard, W., 121, 122.Gerritson, H.J., 69.Gertner, D., 223.Geschwind, S., 79.Geske, D. H., 76.Gesser, H., 438.Gewanter, H. L., 210, 224.Geyer, R., 454.Geymer, D. O., 103.Ghatge, B. B., 218.Gheorghiu, C., 441.Ghose, A., 470.Ghose, R., 288.Ghose, T., 54.Ghosh, C., 285.Ghosal, S., 288.Ghuysen, J. M., 342.Giacometti, G., 37.Giambrone, S., 263.Giannini, U., 150.Gibalewicz, J., 61.Gibbins, S. G., 120.Gibbs, A. J., 501.Gibbs, J. H., 112.Gibson, G., 153.Gibson, J. F., 74, 499.Gibson, M. E., jun., 457.Gibson, M. S., 291.Gibson, Q. M., 91, 92.Giddings, J. C., 31, 429,430, 435, 436, 437.Gidley, J. A. F., 459.Gielen, W., 221, 378.Gierst, L., 99, 100.Giesemann, H., 267.Giesselmann, G., 452.Giglio, M., 477.Gigucre, P.A., 129, 133.Gil-Av, E., 243.Gilbatrick, L. O., 88.Gilbert, A. H., 423.Gilbert, A. R., 127.Gilbert, B., 287.Gilbert, W. W., 154.Gilderson, P. W., 32.Gilham, P. T., 251, 296.Gilkerson, W. R., 85.Gill, D., 98.Gill, E. K., 29.Gill, N. S., 62.Gillam, I. C., 339, 340.Gillespie, R. J., 81, 85, 88,132, 241.515Gaeke, G. C., jun., 416.Ganshirt, H., 432.Gafner, G., 490.Gager, K. H., 87.Gagnaux, P., 56.Gagneaux, A., 167.Gailar, N. M., 46.Galasyn, V., 139.Gal’chenko, G. L., 20, 21.Gale, L. H., 247.Gale, P. H., 403.Gale, R. H., 456.Galik, V., 254.Gall, J. S., 89, 173, 176.Gallagher, Y. K., 23, 88.Gallais, F., 65.Galliland, A. A., 22.Galloway, B., 297, 351.Gallup, G.A., 52.Galt, R. H. B., 256, 277.Gamble, J. L., 406.Ganis, P., 108.Gaoni, Y., 184, 231, 274.GArate, M. J., 442.Garbarini, J. J., 315.Garbisch, E. W., 185.Garbuglio, C., 490.Garcia, E. E., 195.Garcia, E. J., 373.Garcia, H., 313.Garcia GonzAlez, F., 337.Gard, J. A., 486.Gardner, J. N., 211.Gardner, P. E., 350.Gardos, G., 389.Garegg, P. J., 349.Garing, J. S., 46.Garn, P. D., 460.Garner, F. H., 64.Garret, R. H., 402.Garrett, E. R., 180.Garrison, M. C., 25.Garz6n Ruipkrez, L., 440.GaspariC, J., 431.Gasser, R. P. H., 81, 139.Gatehouse, B. M., 459.Gatlow, G., 25.Gatti, R., 36.Gauhe, A., 345.Gaurary, B. S., 70.GavilAn, J, M., 283.Gavrilova, L. P., 303.Gedansky, S. J., 453.Gee, G., 103, 108, 110, 112,Geiger, A., 368.Geiger, F.E., 55.Geil, P. H., 109.Geissman, T. A., 258.Geller, L. E., 63, 203, 316.Geller, S., 125, 468, 476,Gellert, H.-G., 125.Gellert, M., 19.Gel’man, N. E., 452, 453.George, A., 14.113.485.Gilliam, 0. R., 71.Gillis, R. G., 66.Gilman, D. J., 269.Gilman, H., 116, 127, 128.Giner, J., 100.Gingrich, N. S., 471.Ginsberg, A. E., 269.Ginsburg, V., 297.Girado, M., 369.Girgis, Y. M., 56.Giri, K. V., 345.Givner, M. L., 455.Gjems, O., 426.Glabisz, U., 444.Gladstone, C., 361.Gladstone, L., 304.Glaser, L., 297.Glassman, E., 302.Glazier, E. R., 258.Glemser, O., 134, 155, 425.Glick, D., 457.Glick, R. E., 112.Glissman, A., 37.Gloor, U., 402.Glover, G. M., 56, 195.Glukhovtsev, V.G., 238.Glushko, E. I., 139.Glynn, I. M., 380, 381, 383,Godard, H. P., 413.Godin, P., 280.Godtfredsen, W. O., 308.Goehring, O., 234.Goering, H. L., 173.Gottlicher, S. , 464.Goetz, H., 64.Gijtz, M., 290.Goffinet, B., 311, 323.Goggin, P. L., 81, 125.Golab, T., 326.Golben, M., 85.Gold, L. P., 55.Gold, V., 161, 171, 181,Goldby, S. D., 138.Goldenberg, C., 248.Golding, R. M., 84. 135.Goldkoop, J. A., 470.Goldsmith, G. J., 468.Goldstein, D., 419, 421.Goldstein, G., 425.Goldstein, I. J., 338, 347.Goldthwait, D. A., 298,Goldwasser, E., 364.Goldwhite, H., 174, 207.Goldzieher, J. W., 455.Golebiewski, A., 184, 232.Goliasch, K., 246.Golosova, L. V., 431.Gompper, R., 267.GonzAlez, A. G., 283.Gonzalez, C., 359.Gonzales Vidal, J., 166.Good, W.D., 13, 14.Goodgame, D. M. L., 161.392.186.361516 INDEX OF AUTHORS’ NAMES.Goodman, L., 294, 295,Goodman, J. J., 315.Goodwin, H. A., 140.Goodwin, S., 283.Goosen, J., 289.Gopinath, K. W., 285, 286.Gordon, A. R., 85, 86.Gordon, A. S., 34, 40.Gordon, D. A., 63.Gordon, H. T., 433.Gordon, J. J., 229, 238.Gordon, J. P., 69.Gordon, L., 442.Gordon, R. S., 380.Gordon, S., 413, 461.Gordy, W., 72.Gore, M. B. R., 371, 375.Gore, T. S., 451.Gorin, G., 457.Gorin, P. A. J., 331, 334.Goring, D. A. I., 106, 107.Gornick, F., 103.Cornostaeva, S. E., 225.Gorokhov, L. N.. 26.Gorsich, R. D., 149.Gosh, D. K., 72.Goto, T., 309, 314, 326.Gotsmann, U., 267.Gottlieb, 0.R., 258.Gottschalk, A., 377.Coubeau, J., 123, 127, 129.Goudswaard, A., 422.Gould, D., 312.Gould, F. E., 196.Cloulden, J. D. S., 82.Goutarel, R., 288.Govindachari, T. R., 249,285, 286, 293.Gowenlock, B. G., 31, 33.Grace, J. A., 168.Grabner, H., 123.Graf, J. C. B., 418.Graff, S., 368.Graham, B. A., 252.Graham, E. B., 108.Graham, J., 289.(haham, J. D., 168, 239.Graham, R. J. T., 431.Graham, R. P., 441.Graham, S. I., 422.Graham, W. H., 173, 240.Grandberg, I. I., 426.Grant, D. M., 98.Grant, F. W., 175, 222.(;rant, M. S., 275.Grant, P. K., 255.Grashey, R., 193.Gratch, S., 113.Gray, A. H., 279.Gray, E. D., 354, 355, 359.Gray, E. G., 370, 372.Gray, €1. B., 142, 143.Gray, J. A. B., 372.Grazi, E., 332.GrcleniC, D., 128, 132.336, 340.Greco,.C.V., 195.Greely, R. S., 88.Green, D. B., 396, 397, 400.Green, D. W., 496, 501.Green, G. W., 55.Green, J., 279.Green, J. H. S., 10, 32.Green, J. P., 351.Green, L. G., 20, 21.Green, M. L. H., 146, 152,Greenberg, G. R., 358.Greenberg. L. J., 457.Greenberg, S., 313.Greenwood, C. T., 348.Greenwood, N. N., 23, 121,Grkger, I<. M., 449.Gregoriou, G. A., 325.Gregorowicz, Z., 446.Gregory, H., 211, 326.Gregory, N. W., 26, 156.Greig, C. G., 343.Gresham, T. L., 9.Gresser, J., 193.Grey, T. F., 205, 217.Grib, A. V., 185.Gribben, T., 436.Grigat, E., 242.Grigor, J. A., 478.Grigorenko, I. N., 428.Griffin, A. C., 354.Griffin, C. E., 217, 239.Griffith, J. H., 110.Griffith, J.S., 68.Griffith, W. P., 168.Griffiths, J. E., 130, 152.Griffiths, J, H. E., 69.Griffiths, T. R., 77, 83.Grim, S. O., 207.Grimes, G., 444, 451.Grimison, A., 194, 195.Grimley, K. T., 24, 159.Grimmer, G., 314, 327,Grimshaw, J., 280.Grinstead, R. R., 202.Gripenberg, J., 278.Grisar, J. M., 244.Grishin, 0. M., 188.Griswold, E., 115.Grob, C. A., 232.Grob, R. L., 436.Groger, D., 282.Groennings, S., 437.Gr6f, T., 220.Grrnwald. F., 478.Gross, E., 389.Gross, G., 280, 281.Gross, H., 225, 265.Gross, P., 22.Gross, P. M., 57.Grosse, G., 481.Grossowicz, N., 457.Grove, E. L., 448.Grove, J. I?., 256, 260.153, 209.125.428.Groves, I-’. T., 166.Grubert, H., 233.Griiger, G., 344.Gruenfeld, N., 293.Grunbaum, B.W., 432,Grunberg-Manago, &I., 303,Grundfest, H., 369.Grundon, M. F., 285.Grundschober, F., 336.Grunwald, E., 89, 98, 173.Grunze, H., 296.Grunze, I., 131.Grzeskowiak, R., 66.Gudzinowicz, B. J., 438,Gukgan, R., 216.Guenebaut, H., 44.Giinter, B., 125.Guenther, A. H., 47.Guerrin, G., 447.Guggenheim, E. A., 89.Guilbault, G. G., 445.Guittard, M., 153, 478.Gulavane, S. V., 427.Gumargaliera, J. Z., 105.Gumby, W. L., 209.Gundermann, K.-D., 261.Gundry, H. A., 12.Gundyrev, A. A., 55.Gunew, D., 429.Gunn, E. L., 453.Gum, S. R., 20, 21, 25.Gunstone, F. D., 219.Gupta, A. K. S., 258.Gupta, P. R., 107.Gupta, R. P., 112.Gurevich, A. I., 229.Gusev, S. I., 441.Gustin, G. M., 451.Gustus, E. L., 327.Gut, M., 258, 314, 325.Gut, R., 156.Gutbier, G., 451.Guthrie, R.D., 331, 337,Gutmann, V., 130.Gutowsky, H. S., 75, 98.Gutsche, C. D., 89, 243.Gutschik, E., 223.Guttmann, W., 453.Guy, R. G., 151.Guzzo, A. V., 69.Gwinn, W. D., 48, 55.G p , L. I., 445.Haack, E., 290.Haahti, E., 437.Haarstad, V., 270.Haas, R. M., 87.Habel, D., 127.Haber, C. P., 131.Habgood, H. W.. 437.Hackett, C. B., 421.Haddad, Y. M. Y., 307.433.360, 361.449.338INDEX OF AUTHORS' NAMES. 517Hadinec, I., 162.Hadii, D., 116.Haege. L., 381.Haegele, W., 280.Haendler, H. M., 135.Hafner, K., 246.Hafner, W., 142, 147.Hafter, R. E., 369.Hagedorn, I., 452.Hagemann, G., 343.Hagenbach, R., 333.Hagenmuller, P., 124, 479.Hagihara, B., 398.Hagihara, N., 145, 146,Haguenauer, D., 42 1.Haguenauer-Castro, D.,Hahn, E., 245.Hahn, E.L., 67.Hahn, F. L., 411, 418.Hahn, H., 154.Hahn, L. A., 381.Hahn, R. B., 442.Haines, A. H., 272, 331.Hair, M. L., 160.Hajbs, A., 200.Hajos, Z. G., 265.Hakkila, E. A., 425.Hakim, A. A., 359.HalQsz, L., 412.Halevi, E. A., 60, 181,Halford, R. S., 65.Hall, B. D., 303.Hall, D., 162, 164.Hall, D. N., 95.Hall, G. E., 222.Hall, G. G., 53.Hall, J. R., 127.Hall, R. A., 423.Hall, R. J., 217, 423.Hall, T. P. I?., 69.Hallada, C. J., 85.Haller, W., 79.Hallsworth, A, S., 200.Halmann, M., 46, 49, 181.Halpern, J., 84, 88, 117,Halpern, Y. S., 457.Halpin, J. C., 110.Halsall, T. G., 257.Haltner, A. J., 65.Hamamoto, K., 324.Hamann, V., 449.Hambling, J.K., 192.Hamer, N. K., 181.Hamer, W. J., 79, 87.Hamilton, J. A., 251.Hamilton, J. B., 452.Hamilton, J. K., 349.Hamilton, K. J., 347.Hamilton, L. D., 301.Hamilton, P. B., 435.Hamilton, R. J., 305.Hamilton, S. B., 252.233, 234.419.183.138.Hammaker, G. S., 139.Hammarberg, G. , 431.Hammell, L., 461.Hammes, G. G., 92, 94, 95,Hammett, L. P., 169.Hammond, G. S., 170, 173,Hammond, P. R., 220.Hamor, T. A., 285, 493.Hamrick, P. J., jun., 205.Hanahan, D. J., 220.Hance, P. D., 250.Hancock, E. B., 341.Handler, G. S., 203.Handley, R., 10.Handley, T. H., 425.Hanic, F., 487.Hankes, L. V., 415.Hannah, J., 201, 270.Hans, A., 456.Hansen, R. L., 168.Hansen-Nygaard, L., 48.Hanson, A.W., 490.Hanson, H. &I., 52.Hanson, J. R., 256, 277.HanuH, V., 99.Harbers, E.. 361.Harcourt, R. D., 193, 195,Hardegger, E., 279.Hardel, K., 163.Harden, G. D., 32.Harder, R. J., 133, 206,Harding, M. ill., 162.Hardy, A., 479.Hardy, W. B., 225.Harc, D. G., 166.Haresnape, J. N., 435.Harlord, C. G.. 354.Hargreaves, G. B., 136,Harker, D., 496.Harkness, A. C., 84, 117,Harley-Mason, J ., 285,Harmon, K. M., 166.Harned, H. S., 87, 155.Harper, D. O., 12.Harper, F. R., 492.Harper, J. L., 459.Harpur, R. P., 427.Harrington, R. E., 31.Harris, C. M., 62, 161, 163.Harris, D. N., 433.Harris, E. J., 370, 380,Harris, G., 297.Harris, J. E., 385.Harris, J. F., jun., 210,Harris, P. V., 84.Harris, W. E., 437.Harrison, A.G., 2ti, 27.194.188.276.210, 224.158, 160.138.493.381, 382, 383, 392.223, 221.Harrison, B. C., 120.Harrison, D., 178.Harrison, I. T., 321.Harrison, K., 409.Harrison, P. M., 494, 501.Harrison, W. A., 291.Harrop, D., 10.Hart, F. A., 56, 139, 153.Hart, H., 166, 224.Hart, P. B., 85.Hart, R. G., 495.Hartley, P. N., 112.Hartley, S. B., 15.Hartman, L., 219.Hartman, S., 176.Hartmann, R., 245.Hartridge, H., 91.Hartshorne, N. H., 26.Hartwimmer, R., 149.Harvey, J. S. M., 79.Harvey, S . H., 176.Harwood, H. J., 219.Hasbrouck, R. B., 196.Haselkorn, R., 304.Hasek, W. R., 133, 206,Haslam, J., 410, 452.Hassel, O., 136, 140, 248,Hassid, W. Z., 207.Hastings, A. B., 386, 393.Hastings, J., 156.Hastings, J.M., 466.Hasty, T. E., 71.Haszeldine, R. N., 127,Hatcher, J..T., 415.Hatefi, Y., 403, 409.Hathaway, B. J., 162.Hatt, B. A., 485.Hatt, H. H., 218.Hatton, W. E., 9.Haun, R., 337.Hauptman, H., 463.Hause, C. D., 47, 64.Hauser, C. R., 205, 272.Hauser, T. R., 420.Hauw, C., 490.Havinga, E., 242, 321,Haworth, D. T., 123.Haworth, W. N., 339.Hawthorne, M. F., 120,121, 124, 198, 239.Hay, A. S., 209.Hayano, M., 325.Hayatsu, R., 324, 325.Hayes, D. H., 250.Hayes, J. R., 434.Hayes, R. A., 112.Hayes, W., 69, 70.Hayes, W. K., 250.Hayman, C., 16, 22.Haynes, L. J., 255, 260.Haynes, R. C., 297.Hayter, R. G., 153.230.483.260.322518 INDEX OF AUTHORS’ NAMES.Hayward, L. D., 341.Heacock, J. F., 193, 227.Head, E.L., 16.Heady, H. H., 441.Heal, H. G., 62, 118, 134.Heald, P. J., 369, 374.Hearn, W. E., 421.Heasell, E. L., 94, 95.Heath, D. F., 44.Heath, E. C., 297.Heaton, B. G., 244.Hebb, C. O., 372.Hecht, F., 426.Hecht, K. T., 46.Hecht, L. I., 357, 361.Hecht, S. O., 332.Heck, R. F., 147, 151.Heckmann, K. D., 387.Hedberg, K., 49.Hedgley, E. J., 329, 335.Heffernan, M. L., 193.Heftmann, E., 325.Heidelberger, C., 361, 429.Heidelberger, M., 350.Heidner, R. H., 457.Heilbronner, E., 184.Hein, D. W., 225.Heine, H. W., 260.Heinrich, B. J., 451.Heintz, E. A., 155.Heitland, H.- J., 159.Hell, H., 267.Heller, C., 72.Heller, C. A., 40.Heller, M., 315.Heller, W., 66, 107.Hellmann, H., 343.Helmholtz, L., 69.Helminiak, T.E., 103.Hemming, F. W., 216.Hemmings, A. W., 429.Hems, R., 380, 387.Henbest, H. B., 196.Henderson, C. L., 417.Henderson, M. J., 380.Hendlin, D., 400.Henner, E. B., 438.Henry, M. C., 128, 204.Henseke, G., 344.Hensler, R. H., 293.Hepfinger, N., 437.Hepler, L. G., 19, 23.Heppel, L. A., 303, 359,Heras, M. J., 36.Herber, R. H., 130.Herbert, E., 299, 302, 357,Herbert, J. B. M., 112.Herbert, J. R., 279.Herbig, K., 191, 226.Herbst, D., 250.Herbst, P., 211.Herbstein, F. H., 490.Heri, W. J., 346.Herington, E. F. G., 10.360.361, 362.Herlinger, H., 266, 273.Herman, R., 52, 59.HermAnek, S., 313.Hermann, R. B., 313.Hermans, T., jun., 182.Hermans, P. H., 108.Hermodsson, Y., 135.HernAndez, B. R., 283.Herout, H., 251.Herout, V., 249, 252, 259,Herpin, A., 467.Herring, D.L., 131.Herrington, K. D., 154.Herrmann, A., 449.Herrmann, G., 426, 434.Herron, J. T., 27.Herschbach, D. R., 48, 54.Hershey, A. D., 429.Hertler, W. R., 315.Hertz, H. G., 81.Herwig, W., 148.Herz, W., 251, 259.Herzberg, G., 38, 43, 44,Herzog, S., 155.Heslinga, F. J. ill., 431.Heslop, R. B., 115.Hess, D. C., 424.Hess, H., 375, 391.Hettwer, E., 440.Hetzer, H . B., 86.Heubach, E., 127.Heumann, F. K., 437.Heusler, K., 310, 317, 321.Heusser, H., 311.Hevesy, G. C., 381.Hey, D. H., 192, 193.Heymer, G., 18.Heymks, R., 311.Heyn, A. H. A., 440.Heyndryckx, P., 430.Heyns, K., 163, 343.Heyrovskjr, A., 440, 445,Heyworth, R., 343.Hiatt, H.H., 357.Hibbits, J. O., 425, 427.Hickinbottom, W. J., 203.Hicks, G. P., 442.Hicks, M., 93.Hieber, W., 56, 142, 143,Hietanen, S., 87, 154, 163.Higashimura, T.. 102.Higgins, C. E., 422.Higham, P., 276.Hildenbrand, D. L., 9, 12.Hill, A. G., 445.Hill, E. A., 233.Hill, J. A., 461.Hill, R. D., 117.Hill, T. L., 57.Hiller, R. E., 52.Hillman, H. H., 369.Hillman, M., 120.436.45, 59.446.144, 145, 150.Hilmer, W., 486.Hilmoe, R. J., 359, 360.Hilschmann, N., 500.Hilton, I. C., 136, 187,Himoe, A,, 187.Himwich, H. E., 385.Hindman, D., 112.Hindman, J. C., 141.Hine, J., 173, 175.Hingerty, D., 385.Hinman, R. L., 194, 266.Hino, J. B., 207.Hinshelwood, (Sir) C. N.,28, 33, 34, 35.Hirai, N., 103.Hirai, S., 319.Hirokawa, S., 493.Hirota, E., 55.Hirota, N., 75.Hirs, C.H. W., 500.Hirsch, E., 84.Hirsch, P. B., 471.Hirschmann, R., 309; 314.Hirshfeld, F. L., 482.Hirshfeld, M. A., 52, 59.Hirst, E. L., 347, 349, 350.Hirst, R. C., 98.Hisatsune, I. C., 48, 51,53, 59, 129.Hishta, C., 438.Hites, R. D., 120.Hively, R. A., 439.Hoa, H. A., 202.Hoagland, M., 361.Hoard, J. L., 118, 472.Hobbs, M. E., 57.Hobey, W. D., 75.Hoch, F. L., 408.Hochstein, F. A., 229.Hocke, H., 428.Hodges, R., 254, 255,305.Hodgkin, A. L., 370, 371,375, 380, 382, 383, 390.Hodgkin, D. C., 494.Hodson, H. F., 285, 288.Hoefnagel, M. A., 220.Hoft, E., 225.Hoel, D. C., 452.Hoenes, H. J., 426.Hoes, D. A., 457.Hoeve, C. A. J., 104, 111.Hover, H., 229, 240, 241.Hofer, P., 327, 328.Hoff, E.W., 113.Hoffer, M., 294.Hoffman, I., 460.Hoffman, J. D., 109.Hoffman, J. F., 389.Hoffman, J. M., 46.Hoffman, W. M., 461.Hoffmann, C. W. W., 477.Hoffmann, D., 429.Hoffmann, F., 202.Hoffmann, J. I., 79.188INDEX OF AUTHORS’ NAMES. 519Hoffmann, W., 424.Hoffsommer, R. D., 235,Hofman, P. S., 226.Hofmann, A., 285.Hofmann, G., 164.Hofmann, H. P., 233.Hogan, V. D., 461.Hogfeldt, E., 182.Hogg, J. A., 312.Hohnstedt, L. F., 123.Hoijtink, G. J., 77, 78.Hojo, M., 89, 173.Hokin, L. E., 373, 393.Hokin, M. R., 373, 393.Holand, S., 210.Holasek, A., 439.Holden, K. G., 284.Holland, D. O., 261.Hollas, J. M., 49.Holley, C. E., jun., 16.Holley, R. W., 298.Holliday, A.K., 121, 122.Holm, H. S., 98.Holm, R. H., 56, 62, 160,Holman, R. T., 217:Holmberg, R. W., 71.Holmes, D. R., 108.Holmes, J., 175.Holmes, R., 433.Holmes, R. R., 130, 202.Holmgren, A., 216.Holmquist, H. E., 231.Holser, W. T., 466.Holst, J. J., 437.Holt, A,, 280.Holt, R. J. W., 115.Holtmann, G., 261.Holtzberg, F., 155.Holub, M., 251, 252.Holzbecher, A., 456.Holzkamp, E., 125.Homyakov, K. G., 18.Honeycott, J. B., 121.Honig, A., 55.Honnen, L. R., 27, 166.Honour, B. W., 174.Hood, G. C., 81.Hoogsteen, K., 495.Hoogzand, C., 148.Hooper, C. W., 301.Hooper, G. W., 159.Hope, D. A. L., 64, 83,Hope, D. B., 369.Hope, H., 136, 483.Hopff, H., 226.Hopkins, C. Y., 217.Hoppe, R., 125, 155.Hoppe, W., 470.Hora, F.B., 458.Hora, J., 265.HorACek, J., 450.HorAk, M., 252, 284.Horak, V., 273.277, 310.161.160.Horecker, B. L., 394.Horio, T., 398.Horn, P., 296, 496.Horn, R. C., 438.Horning, E. C., 283, 305.Horning, W. C., 185.Horowicz, P., 382, 383.Horrocks, W. D., jun., 139.Horrom, B. W., 208.Horsfield, A., 76.Horton, D., 341, 343.Horton, G. R., 461.Horvath, N., 368.Hoshino, S., 468, 494.Hoskins, B. F., 62, 163.Hossenlopp, I. A., 12.Hougen, J. T., 64.Hough, L., 330, 339, 341,342, 350, 435.Houghton, R. P., 216.Houpt, P. M., 414.Hoverath, A., 450.Hovey, R. J., 56.Howard, G. A., 216, 259.Howard, J. C., 270.Howard, R. L., 398.Horwatitsch, H., 450, 451.Howden, M. E. H., 306.Howe, C., 377.Howe, J. R., 431.Howell, C.F., 171, 243.Howk, €3. W., 208.Hoye, P. A. T., 176.Hrdy, O., 101.Hristidu, Y., 152.HfivnALE, M., 439.Hsiu Ying Tsai, 348.Huaiyu, Shen, 229.Huang-Minlon, 25 1.Hubbard, R., 372.Hubbard, W. N., 11, 12,Huber, E. J., jun., 16.Huber, G., 342, 343.Huber, L., 131.Huber-Buser, E., 491.Hubik, M., 431.Hudec, J., 145, 246.Hudson, R. F., 181.Hiibel, W., 148.Hiibner, L., 130.Hubsch, H., 451.Hiigel, M., 324.Hulsmann, W. C., 407,Hunig, S., 205, 243.Hiittel, R., 147.Huffman, J. W., 200, 251.Huffman, K. R., 261.Huggard, A. J., 335.Huggins, C. M., 112.Hughes, D. J., 470.Hughes, E. D., 176, 177,Hughes, G. A., 320.Hughes, N. A., 288.16, 17, 247.408.189.Hughes, R. E., 103, 106,472.Huisgen, R., 189, 191,193, 226, 260, 262, 274.Hulatt, M.J., 35.Hulme, R., 127.Hume, D. N., 164, 448.Hume-Rothery, W., 485.Hummel, H., 152, 233.Hummelstedt, L. E. I., 448.Humphrey, B. A., 350.Hunt, G. R., 48, 49.Hunt, H., 12.Hunt, J. B., 141.Hunt, K., 349.Hunsberger, I. M., 195.Hunter, W. H., 261.Huque, hl. M., 106.Hurst, J. J., 249.Hurst, R. A. A., 321.Hurwitz, H., 100.Hurwitz, J., 304, 355, 361,Hush, N. S., 27.Hustidu, Y., 233.Hutchinson, D. W., 298.Hutchinson, H. P., 250.Hutchinson, J. A., 458.Hutchinson, R.. 428.Hutchison, C. A., 78.Hutson, D. H., 330.Huxley, A. F., 370.Huxley, H. E., 501.Huyser, E. S., 207, 271.Hwang, H. C., 271.Hyden, H., 370.IbAiiez, E., 308.IbAiiez, L. C., 317.Ibers, J . A., 46, 118.Ibrahim, R.K., 431.Ichinohe, S., 48.Ichikawa, F., 426.Iczkowski, R. P., 60.Idler, D. R., 324.Ieki, T., 452.Igals, D., 329.Igonin, L. A., 113.Ihrman, K. G., 148.Iijima, T., 51.Iitaka, Y., 494.Ikan, R., 288.Ikemi, T., 230.Iliceto, A., 167.Iliopulos, M. I., 160.Illers, K., 112.Immaura, H., 255.Immer, H., 318.Imoto, E., 216.Imura, K., 102.Inano, M., 339.Ince, A. D., 447.Inczkdy, J., 433.Indelli, A., 89.Ingersoll, L. R., 64.Ingham, R. K., 128.363520 INDEX OF AUTHORS’ NAMES.Inghram, M. G., 24, 159.Ingleby, R. F. J., 285, 493.Ingles, D. L., 336.Ingles, J. C., 423.Ingold, (Sir) C., 141, 176,177.Ingran, D. J. E., 68, 69,70, 73, 74, 499.Ingran, G., 417.Ingran, V. M., 496.Ingri, N., 87, 155.Inhoffen, H.H., 321.Inman, R. B., 302.Innes, K. K., 44, 49.Ino, T., 117.Inoue, S., 343.Inoue, Y., 194.Inouye, Y., 240.Iqbal, S. M., 199, 336.Irving, H., 162, 457.Ireland, R. E., 254.Irmscher, K., 321.Ironside, C. T., 184, 228.Isaacs, N. S., 176.Isaacson, R. B., 224.Isaeva, L. S., 185.Isbell, H. S., 331.Isemura, T., 348.Ishida, S., 108.Ishida, Y., 57.Ishidalk, M., 225.Ishii, H., 324.Ishikawa, Y., 467.Israel, G. C., 188.Israeli, Y., 174.Issa, I. M., 445.Issidorides, C. H., 262.Issleib, K., 127, 130, 140.Ito, K., 63.Ito, S., 225.Iverach, G. C., 291.Ivin, K. J., 13, 105.Iwama, F., 458.Iyengar, P. K., 470.Izrailvech, E. A., 187.Jablonski, W. Z., 447.Jaccarino, V., 69.Jache, A. W., 55.Jack, J., 34.Jackman, L.M., 24, 201,214, 280, 305.Jackson, B. G., 253.Jackson, J. A., 81, 138.Jackson, R. A., 174.Jacob, G., 63, 252.Jacobs, T. L., 212.Jacobs, W. A., 291, 326,Jacobson, M., 218.Jacobson, R. A., 344, 475.Jacobson, N. W., 277.Jacques, J., 312, 315.Jacuna, Z., 171.Jager, H., 324, 326, 328.Jaeger, R. H., 216.327.Jarnefelt, J., 375.J%schke, L., 331.Jaffk, I., 12.Jaffe, J. H., 52, 59.Jaffe, J. J., 357.Jaggi, H., 475.Jahn, D.. 99.Jakob, F., 193.Jakubowski, 2. L., 270.Jakuszewski, B., 24.James, A. L., 297.James, D. B., 443.James, D. H., 180.James, H. M., 62.James, T. C., 44.James, W. J., 492.Jamieson, G. R., 437.Jamison, H. W., jun., 443.Jamres, M., 121.Jankk, J., 437, 438, 439.Janczura, E., 342.Janda, M., 265.Jander, G., 155.Jander, J., 129, 135.Janetos, N.S., 440.Janot, M.-M., 288.Janssen, M. J., 149.Januzzi, N., 47.Janz, G. J., 85.Jarczewski, A., 43 1.Jardetzky, C. D., 296.Jardetsky, 0. E., 81.Jaruzelslti, J. J., 166.Jarvie, A. W., 127, 185.Jaselskis, B., 451.Jasim, F., 426, 427.Jasinski, T., 448.Jassinger, F., 447.Jayadevappa, E. S., 63,Jayaranian, P., 25 1.Jayme, G., 329, 348.Jawan, A., 54.Jaworzyn, J., 106.Jeanloz, R. W., 342, 351.Jecu, M., 448.Jefferies, P. J., 252.Jeffery, G. H., G6.Jeffery, J. d’A., 268.Jeffery, P. G., 415, 417,440.Jeffrey, G. A., 116, 129,469, 486, 491, 492, 493.Jeffs, P. W., 289, 290.Jeger, 0.. 248, 258, 310,315, 316, 317, 318.Jellinek, F., 150, 152, 155,478.Jen, C.K., 73, 74.Jenckel, E., 112.Jencks, W. P., 178, 179.Jenkins, D. R., 126.Jenkins, W. A., 131.Jenner, E. L., 208.Jennings, L. D., 162.Jenny, E. I?., 17G, 191.59.Jensen, B. S., 447.Jensen, E. V., 207, 312.Jensen, F. R., 12, 247.Jensen, L. H., 296, 494,Jensen, M. B., 87, 183.JenSovskj?, L., 162.Jesaitis, 31. A., 357.Jeschke, J. P., 291.Jessup, R. S., 16, 17.Jewell, J. P., 420.Jibben, B. P., 264.Jilek, J. O., 286.Jimkniz-Barber&, J., 127.Jing-Ling Chen., 448.Jochims, J. C., 342.Johansson, G., 125.John, K., 130, 131.Johns, T., 459.Johns, W. F., 311.Johnson, A. E., 176, 237,Johnson, C. C., 452.Johnson, D. McL., 383.Johnson, D. P., 458.Johnson, E. A., 84, 447,Johnson, F. A., 128.Johnson, G.S., 196.Johnson, J., 456.Johnson, J. A., 392.Johnson, J. B., 417.Johnson, J. F., 113, 437.Johnson, J. H., 196.Johnson, J. S., 80.Johnson, L. F., 255, 287.Johnson, M. D., 178, 190,Johnson, R., 151.Johnson, R. C., 161.Johnson, W. H., 18, 20, 22.Johnson, W. S., 11, 203,247, 292, 314, 319.Johnston, D. R., 62.Johnston, H. S., 39, 47.Johnston, J. D., 144.Jolly, W., 132.Jolly, W. J., 21.Jolly, W. L., 76.Jommi, G., 431.Jona, F., 468.Jonasen, M., 162.Jonassen, H. B., 147.Joncich. M. J., 423.Jones, A. S., 295, 343.Jones, D. E., 177, 190.Jones, E. A., 52.Jones, E. R. H., 209, 211,212, 253, 257, 308, 309.Jones, G., 191, 276.Jones, I. G., 348.Jones, J. B., 211, 280.Jones, J. I<. N.. 330, 332,336, 337, 340, 350.Jones, J.M., 183.Jones, J. L., 35, 415.Jones, J. T., 459.495.277, 280.191, 195INDEX OF AUTHORS’ NAMES. 521Jones, L. H., 46, 50, 82,Jones, M. H., 189.Jones, R. A. Y., 194, 269.Jones, R. H., 84.Jones, W. D., 52.Jones, W. H., 115.Jones, W. J., 52.Jones, W. M., 197, 239,Jordan, D. O., 302.Jordan, J., 20, 461.Joska, J., 311, 314.Josse, J., 357.Joussot-Dubien, J., 446.Joyce, C. R. B., 392.Joyner, T. B., 16, 147.Ju-Cheng Hsu, 448.Judd, S. H., 450.Julia, M., 213, 216, 240,Julia, S., 216, 240, 308.Juliano, B. O., 337.Juliard, A., 99, 100.Julietti, I?. J., 219.Juneja, H. R., 280.Jung, H., 130.Junghann, L., 235.Jungreis, E., 420.JureEek, M., 431, 452.Jurjewa, L. P., 233.Jursa, A. S., 47.Juvet, R.S., 437.Kaandorp, A. W., 185.Kaarsemaker, Sj ., 9.Kabasakalian, P., 316.Kachinskaya, 0. N., 9.Kaczlrowski, J., 282.Kaczmarczyk, A., 127.Kadaba, P. K., 175, 222.Kaesz, H. D., 128, 147,Kagan, H. B., 312.Kagarise, R. E., 59.Kahlen, N., 128, 144.Kahlenberg, F., 22.Kahlweit, M., 85.Kahn, J . B., 392.Kahn, M., 141.Kaier, R. J., 459.Kail, J . A. E., 61.Kainuma, Y., 463.Kainz, G., 449, 450, 451.Kaiser, E. T., 206, 243.KakbC, B., 286.Kakudo, M., 108.Kallistratos, G., 430.Kallos, J., 291.Kalman, 0. F., 61.Kalojanoff, A., 280.Kalugina, N. N., 156.Kalvoda, J,, 316, 317.Kamal, T. H., 447.Kamb, W. B., 473, 486.Kamber. B., 317.161.266.241, 308.150.Kamenar, B., 128.Kammen, H. O., 361.Kammermeier, A., 274.Kamper, R.A., 79.Kane, V. V., 257.Kaneko, C., 195.Kaneko, M., 105.Kangle, P. J., 347.Kafiski, M., 433.Kanzig, W., 70.Kaplan, J. I., 98.Kaplan, L., 295.Kaplan, M. L., 89, 173.Kapoor, U., 444.Kaputovskaya, G. V., 119.Karasek, F. W., 436.Karabatsos, G. J., 168,Karabatsos, P. J., 98.Kargin, V. A., 109, 113.Kargl, T. E., 214.Karl, D. J., 85.Karle, I. L., 463.Karle, J., 463.Karmen, A., 438.Karpeiskaya, E. I., 202.Karpetyan, M. G., 229.Karplus, M., 67.Karraker, S. K., 434.Karrer, P., 214, 215, 288,Kartha, G., 493.Kartsev, G. N., 55.Karvelis, N., 22.Kasai, P. H., 55.Kasal, A., 315, 316.Kaspar, E., 310.Kasparow, M., 432.Kaspcr, J. S., 473, 484.Kasper, K., 97.Kassel, L. S., 28.Kassner, J . L., 455.Kasturi, T.R., 200.Kasuya, T., 48.Katagiri, hl., 237.Katlefsky, B., 129.Kato, H., 343.Katritzky, A. R., 194,195, 260, 268, 269.Katz, B., 383.Katz, J. J., 153, 170.Katz, J . L., 487.Katz, T. J., 76, 184, 230,Kawai, T., 107.Kawakita, Y., 368.Kawatani, T., 250.Kawasaki, A., 108.Kay, R. L., 84.Kay, W. B., 129.Kayama, K., 53.Kaye, A., 304, 363.Ke, B., 110.Kearney, E. B., 398.Keavney, J . J., 112.Keat, P. P., 473.239.289.285, 493.Keay, L., 181.Keblys, K. A., 151.Kebrle, J., 310.Keefer, R. M., 187.Keel, E. W., 456.Keeler, R. N., 436.Keen, N., 71, 137.Keenan, T. A., 62.Keeney, M., 429.Kefurt, K., 265.Keilin, D., 397.Keir, H. M., 354, 355, 357.Keith, W. A., 13.KejEi, E., 101.Kelbg, G., 90.Kell, G.S., 85.Keller, A, 109.Keller, L., 326.Keller, R. A., 430.Keller-Schierlein, W., 222,Kelley, H. C., 118.Kellner, S. M. E., 34.Kelly, H. C., 197.Kelly, J . E., 456.Kember, N. F., 430.Kemmitt, R. D. W., 121.Kemp, J. C., 71.Kempter, C. P., 475.Kendall, E. C., 265.Kende, A. S., 228.Kendrew, J. C., 495, 496,Kennedy, A,, 128, 129.Kenner, G. W., 199, 268,Kenner, J., 334.Kent, G. J . , 307.Kent, L. H., 342.Kent, P. W., 340.Kenttiimaa, J., 139.Kerker, M., 86.Kern, D. M., 79.Kern, S., 344.Kern, W., 225.Kernan, R. P., 387.Kerridge, D. H., 163.Kerrigan, J., 122.Kerwin, J . F., 315.Kessler, J. E., 460.Ketley, A. D., 173.Kettle, S. F. A., 144, 145.Kewley, R., 126.Keynes, R. D., 371, 375,382, 383, 384, 387, 390,392.Khachkurazov, G.A., 46.Khalifa, H., 447.Khan, N. H., 291.Kharasch, M. S., 202, 203.Khastgir, H. N., 253.Khastgir, K. N., 278, 311.Khopkar, S. M., 425, 426.Khorana, H. G., 353.Khorlina, I. M., 200.Khosla, 3%. C., 215.229.498, 499.279522Khuri, A., 200.Khym, J. X., 296.Kianpour, A., 14.Kianud-din, M., 195, 276Kielar, E. A., 289.Kielich, S., 60, 66.Kielley, W. W., 397, 391Kierkegaard, P., 479.Kieselbach, R., 436.Kiess, A. A., 200, 219.Kihlborg, L., 156.Kikkawa, I., 285.Kikuchi, C., 69, 70.Kilday, M. V., 18.Killick, R. W., 306.Kilpatrick, M., 185.Kilzev, S. M. L., 122.Kim, Y. S., 348.Bimel, S., 52, 59,Kimel, W., 216.Kimura, K., 56.Kimura, T., 400.Kincl, F. A., 258.King, E.J., 86.King, E. L., 82, 88, 141.King, G. J., 70.King, G. W., 48.King, H. K., 403.King, J. P., 22, 23.King, M. V., 497.King, N. J., 350.King, R. B., 146, 147, 150.King, R. L., 45.King, R. W., 32.King, T. E., 398, 399.King, T. J., 258.King, W. T., 49, 51.Kinghorn, R., 421.Kingsinger, I. B., 106.Kinsolving, C. R., 392.Kipling, J. J., 444.Kirby, G. W., 283, 409.Kirby, K. S., 298.Kirby, K. W., 347.Kircher, H. W., 329.Kirk, D. N., 201, 306, 310.Kirk, P. L., 432, 433.Kirkman, H. N., 297.Kirkwood, J. G., 92, 106.Kirmse, W., 38.Kirshenbaum, A. D., 153.Kirst, H., 454.Kirsten, W. J., 448, 450,Kirtley, M.. 312.Kishida, Y., 324, 325.Kislovskii, L. D., 59.KiSovA, L., 1 G l .Kiss, J-, 221.Kissa, E., 413.Kissman, H.M., 312.Kistiakowsky, G. B., 9, 31,38, 39, 170, 175.Kit, S., 302.Kitagawa, T., 290.Kitahara, Y., 176.452.INDEX OF AUTHORS’ NAMES.Kitano, Y., 434.Kitko, F. V., 421.Kitzinger, C., 24.Kiwa, T. K., 217.Kivelson, D., 48, 77.Kjalberg, O., 337.Klanberg, F., 122, 136,Klassen, N. V., 187.Klebe, J., 175, 210, 239.Klecak, G. L., 454.Kleeman, C. R., 369.Kleemann, E., 434.Klein, F. S., 171.Klein, M. J., 120.Kleinberg, J., 115, 233.Kleiner, L., 247.Kleinermann, M., 100.Kleinspehn, G. G., 263.Klement, R., 131.Klemperer, W., 44, 55.Klenk, E., 216, 221, 377,Kley, W., 470.Klibansky, Y., 307.Klimov, I. T., 424.Kline, R. J., 141.Klingenberg, M., 401.Klingsberg, E., 195.Kloubek, J., 283.Klug, A., 501.Kluiber, R.W., 138.Klyne, W., 63, 256, 305,Knaack, D. F., 207.Knee, T. E. C., 172.Kneubiihl, F. K., 73.Knight, C. ..4., 301.Knipper, J. E., 223.Knipprath, W., 216.Knoll, J. L., 295. .Knolle. H., 329.Knollmiiller, K. O., 131.Knoth, W. H., 213.Knowles, W. S., 202.Knox, J. H., 39.Knox, K., 476.Knutson, D., 226.Knypl, J. S., 417.Kobayashi, H., 252.Koch, M., 457.Kochergina, L. A., 56.Kochetkov, N. K., 241.Kocor, M., 238.Kobrich, G., 227.Kocsis, K., 310.Kochling, H., 343.Koefood- Johnsen, V., 392.Kohler, J., 143.Koehler, W. C., 467, 472.Koenig, J. L., 52.Konigstein, O., 225.Kiirbl, J., 447, 448, 449,Koerner, J. F., 358.Koster, K., 213.157.378.314, 328.450, 457.Koster, R., 121, 125, 282.Koevoet, A.L., 321.Kofler, A., 422.Kogl, F., 220, 222.Kogler, H. P., 123, 145,Kohlmaier, G., 33.Kohlschiitter, H. W., 157.Kohn, E., 166.Kohn, G. A., 474.Kohn, P., 333.Kohnstam, G., 172.Kolbovskii, Y. Y., 106.Kolditz, L., 130, 132.Kolesov, V. P.. 21, 22.Koller, H., 280.Kolling, 0. W., 450.Kollonitsch, J., 203.Kolosov, M. N., 229.Kolthoff, I. M., 101.Kolyadin, A. B., 478.Komatsu, N., 347.Komendantov, M. I., 240.Komers, R., 436.Komkov, A. I., 479.Kondo, T., 255.Kondrashev, Y. D., 119.Kondratenko, B. P., 56.Koningsveld, R., 106.Konogi, H., 359.Konopicky, K., 454.Koob, R. P., 324.Koransky, W., 296.Korndorfer, O., 273.Korenman, I. M., 457.Korev, K. A., 225.Korf, D., 334.Koritz, S. B., 297.Korkisch, J., 434.Korn, E.D., 350.Kornber, A., 304.Kornberg, A., 353, 354,355, 356, 357.Kornberg, S. R., 357.Kornblum, N., 174.Korneev, V. A., 454.Kornev, Y. V., 26.Kornfeld, F., 216.Kornfeld, S., 297.Kornilov, A. N., 20, 21.Korotkina, 0. Z., 105.Korshun, M. O., 452, 453.Korte, F., 260, 273, 324.Kortum, G., 83.Koryta, J., 100, 101, 102.Korytnyk, W., 197.Kosak, A. I., 223.Kossanyi, J., 204.Koshland, D. E., jun., 348.Koski, W. S., 77.Kost, M. E., 153.Kostenzer, 0.. 422.Kotani, M., 53.Kotksek, Z., 429.Kotlinskaya, B., 428.Kouteck9, J., 99, 100, 101.234INDEX OF AUTHORS' NAMES. 523Kovalev, I. F., 49.Kova, J., 283.Kowalewski, D. G., 48.Kowalewski, Z., 329.KozAkovA, M., 431.Kozhina, I. I., 478.Kozikowski, J., 234.Kozina, M.P., 13.Kozloff, L. M., 358.Krakow, J. S., 357, 361.KraljiC, I., 418.Kramer, W. R., 12.Krant, J., 296.Kranz, 2. H., 220.Krapcho, A. P., 168, 239.Kratky, Von O., 106.Kratzer, J., 147.Kratzl, K., 237.Kraus, C. A., 83.Krause, B. H., 456.Krauss, H.-L., 130.Krauss, M., 45.Krausz, I., 430, 440.Kraut, J., 495.Krebs, A., 192, 241.Krebs, H. A,, 369, 370, 380,Kreevoy, M. M., 173.KrejCi, M., 436.KrGpinsk?, J., 249.Krespan, C. G., 152, 210,Kretenik, V. B., 139.Kreutzer, A., 321.Kriebitzsch, N., 150.Krigbaum, W. R., 103,104,Krikorian, 0. H., 484.Krim, S., 108.Krinchuk, G. S., 65.Kriner, W. A., 126.Kringstad, K., 348.Krisher, L. C., 48, 55.Krishna, M. G. P., 50.Krishna-Rao, K. V., 469,Kristen, H., 337.Krivis, A.F., 452.Kroder, W., 144.Krogh, A., 380.Krogh-Moe, J., 123, 471.Kroll, W. R., 125.Kromhout, R. A., 98.Krone, W., 302.Kropf, A., 372.Kruerke, U., 148.Kriiger, M., 234.Krumholz, P., 83.KrupiCka, J., 337.Krupp, F., 125.Kruse, F. H., 153.Kruse, W., 141.Kryder, S. J., 61.Krylov, E. I., 156.Krzeminski, L. F., 215.Kubba, V. P., 281.386, 387.232.105.491.Kubaschewski, O., 18.Kubo, M., 51, 56, 63.Kubota, T., 324.Kucharczyk, N., 273.Kuchen, W., 123.Kuchitsu, K., 46.Kuehner, E. C., 423.Kundig, W., 346.Kuvita, Y., 72.Kuhlborsch, G., 126.Kuhn, H., 345.Kuhn, R., 213, 342, 344,345, 378.Kuhn, S. J., 204.Kuhn, W., 63.Kuivila, H. G., 200.Kukushkin, Y. N., 161.Kulhan, J., 254.Kulichikhina, R.D., 425.Kulkarni, A. B., 229.Kulkarni, A. S., 451.Kulonen, E., 437.Kumamoto, J., 118.Kummer, D., 126, 127.Kumov, V. I., 441.Kunkle, A. C., 55.Kunshin, S. D., 457.Kuntze, H., 222.Kunz, J. L., 89.Kuo, C. H., 235, 277, 310.Kuo, H., 314.Kupfer, D., 314.Kuphal, R., 464.Kuppermann, A., 34.Kureta, M., 104, 105.Kuriki, Y., 297.Kuritzkes, A., 327.Kurokawa, M., 369.Kurosaki, S., 112.Kursanov, D. N., 171, 201,Kurtz, R., 288.Kurtze, G., 94.Kussy, M. E., 426.Kustin, K., 95, 194.Kfita, J., 101.Kuzel, P., 145, 149, 234.Kuz'min, M. G., 241.Kuznetsov, V. K., 424.Kuznetsova, V. K., 417.Kuznetsova, 2. M., 424.Kuzovkov, A. D., 291.Kuzyakov, Y. Y ., 44.Kwei, G. H., 48, 54.Kyburz, E., 235, 277.Kyle, R.E., 289.Kynaston, W., 122.Kyte, C. T., 66.Labarre, J.-F., 65.Labbauf, A., 8, 64.Lkbler, L., 316.Lacher, J. R., 14.Lacina, J. L., 13, 14.Lacourt, A., 430.Ladeinova, L. V., 164.230.Ladell, J., 462.Lagowski, J. J ., 152.Lagowski, J. M., 194, 260,269.Laidler, K. J., 10, 20, 29,35, 89, 179.Laird, M. E., 174.Laird, W., 256.Lajtha, A., 368.Lakhanpal, M., 103.Lakshman, S. V. J., 44.Lakshmikantham, M. V.,Lal, J. B., 448.La Londe, R. T., 206, 243.Lamb, J., 94, 95, 113.Lambe, J., 69, 70.Lambert, J. D., 66.Lambert, J. L., 457.Lambert, R. F., 144.Lambert, R. W., 186.Lamberton, J. A., 220.Lambregts, W. A., 9.Lamchen, M., 263.Lamm, O., 94.Lampe, F. W., 96.Lanceley, H. A., 112, 113.Landau, L., 47.Landauer, S.R., 335.Landgebe, J. A., 241.Landgraf, W. C., 76.Landquist, N., 100.Landsfeld, H., 151.Landsteiner, K., 376.Lane, R. G., 300.Lane, D., 302.Lane, G. H., 305.Lanese, J, C., 451.Lang, A. R. G., 347.Lang, J., 194.Lang, W., 243.Langenbeck, W., 331.Langer, T., 431.Langhammerer, C. M., 208.Langlois, W. E., 437.Langridge, R., 301.Lansbury, P. T., 199.Lapidot, A., 181.Lappert, M. F., 121.Larbig, W., 125.Larcombe, 13. E., 122.Lard, E. W., 438.Lardy, H. A., 397,408,428.Larkworthy, L. F., 166.Larrson, R., 82.Larsen, R. P., 426.Larson, E. G., 159.Larson, J . G., 34.Larson, M. L., 157.Larson, T. E., 429.Larsson, S. E., 332.Laschturka, E., 262, 274.Lash, J. W., 347.Laskowski, D. E., 419.Lassner, E., 444.Laszlovszky, J., 414.293524 INDEX OF AUTHORS’ NAMFLatorre, C., 11.Latyshev, E.F., 159.Laub, H., 430.Laubach, G. D., 201, 306.Laurent, B., 443.Laurent, S., 443.Lauterbach, R., 277.Laurie, IT. W., 47, 48, 54,Lauritzen, J. I., 109.Lavalle, D. E., 157.Lavie, D., 258.La Villa, R. E., 137.Lavin, A. J., 52.Lavrushin, V. F., 166.Law, C. A., 79.Lawrence, J. K., 82.Lawrence, R. V., 254.Lawson, D. E. M., 403.Lawton, R. G., 288.Lainiewski, M., 24.Lea, K. R., 14, 79.Leaback, D. H., 339, 343.Leach, H. F., 23.Leader, H., 261, 431.Leaderman, H., 112.Leaf, A., 380, 386, 387, 388.Leal, G., 168.Le Baron, F. N., 379.Le Bas, C. L., 88.Lebedev, R. V., 51.Le Bel, N. A., 248, 273.Le Blanc, F. J., 47.Le Blanc, 0.H., 48, 55.Le Corre. Y., 466.Lederer, E., 217, 324.Le Dizet, L., 337.Le Fhvre, C. G., 57, 65.Le Fhvre, R. J. W., 55, 57,Leffek, K. T., 183.Leffler, A. J., 127.Lefkowitz, I., 470.Lee, C. A,, 55, 67.Lee, C. M., 279.Lee C. P., 399.Lee, F. S., 479.Lee, H. H., 209, 212.Lee, J. B., 335, 337.Lee, J. D., 492.Lee, W. W., 295.Leeming, P. R., 211.Lees, M., 378.Leete, E., 326.Legaye, F., 44.LCgrkdi, L., 443.Legrand, M., 313, 450.Le Hir, A., 288.Lehman, I. R., 304, 353,355, 356, 401.Lehmann, H.-A., 123.Lehmann, J., 345.Lehmkuhl, H., 125.Lehninger, A. L. 397, 406,Leibman, K. C., 361.55.61, 65, 66.408.Leibowitz, J., 339, 341.Leigh, G. J., 127.Leighton, F., 37.Leiser. K. H., 124.Leisten, J. A., 180.Leitinger, F., 339.Leitman, Y.I., 23.Le Men, J., 388.Lemieux, R. U., 340, 345.Lemons, J. F., 81, 138.Lendle, W., 205.Lenk, W., 229.Lennartz, H., 367.Le Noble, W. J., 174.Le Ny, G., 244.Lenz, R. W., 339.Leonova, V. V., 124.Lepage, G. &4., 361.Lerner, M., 422.LeRoy Salermi, O., 175.Lesage, M., 239.Leslie, R. T., 423.Lester, R. L., 397, 400,Letsinger, R. L., 282.Lettau, H., 267.Lettenbauer, G., 290.Leussing, D. L., 23.Leutner, H., 154.Lew, H., 55.Lewandowski, A., 431.Lewis, B., 468.Lewis, E. S., 183, 190, 191,Lewis, H. R., 69.Lewis, J., 62, 76, 117, 144,Lewis, K. G., 170.Lewis, T. B., 315.Lewitsch, W. G., 99.Levallois, C., 216.Levi, D. L., 22.Levi, M. C., 430.Levin, I., 181.Levina, R. Ya., 10, 241.Levine, A.S., 377.Levine, R., 269.Levine, S. G., 248, 312.Levitus, R., 148, 158.Levy, H. A., 80, 133.LCvy, J., 288.Levy, P. W., 71.L6vy, R., 451.Li, C.-L., 370, 386.Liang, C. Y., 108.Liberles, A., 261.Liberti. 154.Libet, B., 391.Libowitz, G. G., 117, 137.Lichtenstein, J., 357.Lichti, H., 256, 328.Lichtin, N. N., 83, 85,Liddel, G. U., 325.Lide, D. R., 48, 54, 55,403.226.152, 157.167, 222.60.Lidiard, A. B., 65.Lidov, R. E., 247.Lieb, H.. 439.Liebau, F., 486.Liebenberg, D. H., 64.Liebig, G. F., jun., 416.Liehr, A. D., 138.Liehr, W., 127.Lieser, K. H., 88, 163,Lietzke, &I. H., 81, 88.Lifshitz, A., 92.Lifson, S., 104.Light, R. J., 272.Liisberg, S., 308.Likhosherstova, V. N., 453.Lima, F.W., 440.Lincoln, K. A., 413.Linday, E. ill., 429.Lindberg, B., 330, 332,Lindberg, J. J., 55.Lindberg. M. L., 478.Lindberg, U., 235.Linde, H., 328.Lindeman, L. P., 437.Linrlemann, G., 486.Lindley, G., 414.Lindqvist, I., 130, 154,Lindsay, M., 122.Lindsey, R. V., 129.Lindsey, R. V., jun., 207.Lindstrom, F., 447.Lin&k, A., 162.Ling, G., 382,.383.Lingafelter, E. C., 162,Lingens, I?., 343, 344.Link, W. E.. 439.Linklater, M., 107.Links, J., 402.Linn, B. O., 403.Linnantie, R., 173.Linnett, J. W., 30.Linstead, R. P., 201, 218,Lionetti, F., 393.Lions, F., 140.Lipkin, D., 297, 344.Lipman, C., 251.Lipmann, F., 408.Lipowitz, J., 437.Lipp, M., 216.Lippincott, E. R., 45.Lipscomb, R. D., 126.Lipscomb, W.N., 121, 125,Lipsett, M. N., 303.Lipshitz, R., 298.Liptay, G., 461.Lisitsyna, E. V., 422.Lisk, D. J., 452.Li-sten, Li., 109.Lister, M. W., 84, 158.Liston, T. V., 189.426.349.484, 493.482.270.344, 463, 475, 489, 493Liteanu, C., 443.Litt, M., 108, 304.Littauer, U. Z., 302, 303.Little, R., 46, 54.Littleman, M. L., 457.Litvinchuk, V. N., 157.Liversedge, F., 490.Livingston, R., 71, 72, 74.Livingstone, S. E., 161.Ljunggren, S., 94.Llanos, R., 236.Llewelyn, G. I. W., 63.Llewellyn, F. J., 162.Llewellyn, J. A., 176, 183.Lloyd, H. A., 283.Lloyd, K. W., 441.Lloyd, P. F., 343, 345.Loan, V., 222.Lobacher, A. N., 465.Lock, M. V., 203, 350.Lodding, W., 461.Loder, J. D., 212.Lochner, A., 149, 233.Loeffler, J.E., 277.Leoffler, M. C., 9.Lowdin, P.-O., 53.Liiwe, I., 136.Loewenstein, A., 81, 98.Loewenstein, W. R., 372.Loewenthal, H. J. E., 254,Loft, J. T., 223.Logan, N., 162.Logan, T. J., 107.Logothetis, J., 429.Lohman, F. H., 131.Lohmann, D. H., 161.Lohr, L. J., 449, 459.Lohse, F., 279.Lomardo, P., 246.Lombardo, G., 138.Long, C., 378.Long, D. A., 51, 125, 221.Long, F. A., 42, 86, 95, 181,182, 186.Long, L. H., 15, 33.Long, M. W., 48.Longi, P., 124.Longman, R. T., 305.Longmuir, N. M., 388.Longuet-Higgins, H. C.,Lonsdale, K., 63, 469,Loomans, M. E.. 275.Lord, P. A., 340.Lord, R. C., 45.Lord, S. S., jun., 455.Lorenz, I., 222.Lorkiewicz, 2.. 300.Los. J. M., 100, 102.Loshack, S., 113.Lossing, F.P., 26, 27.Lotspeich, J. F., 54.Lott, K. A. K., 69, 159.Lott, P. F., 440.312.68, 184, 232.472, 491.INDEX OP AUTHORS’ NAMEL,ouise, I<. D., S7.Lovell, F. RI., 493.Lovell, H. L., 456.Lovell, R. J., 52,Lovett, S., 432.Loveluck, G. D., 57.Low, B. W., 482.Low, W., 68, 69.Lowe, G., 201, 253.Lowe, J. P., 177.Lowitzsch, K., 462.Lowry, 0. H., 370.Loyd, R. J., 436.Luborsky, S., 360.Lucius, G., 216.Ludwig, H., 429.Liibbers, D., 92.Lugasch, M. N., 166.Luhleich, H., 126.LukeS, R., 265, 283.Luke& V., 436.Lukinykh, N. L., 22.Lumry, R., 93.Lund, E. J., 388.Lund, L. G., 130.Lundegardh, H., 388.Lundin, A. G., 468.Lung, M., 330.Lunt, E., 244.Lutskii, A. E., 56.Luttinger, L. B., 209.Lutz, E. F., 262.Lutz, G., 469.Luzzati, V., 296, 495, 501.Luz, z., 98.Lyle, G.G., 270.Lyle, R. E., 270.Lyles, G., 416.Lynch, P., 377.Lynen, F., 215.Lynn, J. W.. 221.Lynton, H., 153.Lyon, R. J . P., 459.Lyons, C. E., 246.Lysenko, V. I., 422.Lythgoe, R., 308, 321.Lyubina, S. Ya., 107.Ma, T. S., 412, 440.Mabbs, F., 62.McArdle, A. H., 354.McAuley, A., 87.McBride, W. R.. 13.McCall, D. W., 102, 112.McCallum, G. H., 494.McCallum, K., 128.McCallum, W. A., 25.McCapra, F., 307.McCarthy, J. L., 330.McClelland, A. L., 116.McCleverty, J. A.. 152.Maccoll, A., 32, 170.McColl, D. W., 98.McConnell, H. M., 68, 72,75, 77, 79, 08.McCorkindale, N. J., 261.626hIcCormack, J. I., 382.McCoskey, R. E., 16.McCoy, P. F., 420.McCrae.W., 209.McCrindle, R., 237, 242.McCrum, N. G., 113.McCullough, J. D., 136,McCullough, J. P., 12, 13,McCullough, R. L., 82,McCurdy, W. H., jun.,McCusker, P. A., 122.MacDiarmid, A. G., 126,Macdonald, A. M. G., 412,McDonald, B. J., 154, 474.MacDonald, D. L., 331.McDonald, J. E., 22.McDonald, L. A., 435.MacDonald, M. H., 117.McDonald, R. A., 9, 12.McDonald, R. N., 224.McDonald, T. R. R., 465.McDowell, C. A., 75.McDowell, R. S., 50.Macek, A., 432.McEwen, W. E., 233.Macey, W. A. T., 66.McFarland, J. W., 250.McGarvey, B. R., 305.McGarvey, J. E. B., 285.McGeachin, H. McD., 130.McGee, M. A., 266.McGhie, J. F., 205, 217,MacGillavry, C. H., 466,McGill, B. B., 356.McGinnis, E. A., 44.McGrath, W. D., 41.McGreer, D.E., 241.McGuire, D., 437.McHale, D., 279.Machida, S., 339.Rlachin, D. J., 157.Machleidt, H., 218.McIlwain, H., 367, 369,370, 371, 373, 374, 375,376, 378, 379, 386.McIntosh, J., 112.Macintosh, W. D.. 423.Mack, W., 191, 226.MacKay, A. L., 466.McKay, F. C.. 226.McKean. D. C., 49, 127.MacKellar, F., 209, 305.McKibbin, J. M., 401.Mackie, I. M., 349.McKinley, W. P., 422.McKinney. C. N., 44.McI<inney, T. hI., 161.Mackle, H., 7, 13, 26.477, 484.14.161.445.132.443, 457, 458.219.494526 INDEX OF AUTHORS’ NAMES.McKusick, B. C., 210, 232.MacLachlan, A., 172.McLachlan, A. D., 71, 75.McLain, W. H., 41.McLaughlin, D. E., 122.MacLean, D. B., 291.McLean, S., 287.McLennan, H., 384, 386.Macleod.N., 457.McLoughlin, B. J., 282.MacMillan, J., 256, 260.McMillan, J. A., 163.McMilland, J. A., 74.McMullan, R., 116.McMurray, W. C., 408.McMurray, W. W., 397.McMurry, T. B. H., 249,MacNally, S., 335.McNesby, J. R., 34.McOmie, J. F. W., 27?.RkPhail, A. T., 251.McPree, D. O., 126.McQuarrie, D. A., 48.McRae, W., 274.McReynolds, A. W., 470.McRobbie, E. A. C.. 380.McSweeney, G. P., 336.McTigue, P. T., 174.MAczay, L., 429.Maeck, W. J., 426, 427.Maeda, K., 193.Magerlein, H., 325.Mackle, H., 26.Maffly, R. H., 387.Magasanik, B., 358.Magdoff, B. E., 501.Magee, R. J., 426, 427.Magerlein, B. J., 312.Maggio, F., 56, 161.Magnani, A., 315.Magnasco, V., 107.MagnCli, A., 156, 476.Magnum, B. W., 78.Magnuson, D.W., 55.Magnusson, B., 127.Magnusson, R., 234.Mah, A. D., 16.Mahan, B. H., 31.Mehler, H. R., 363, 364,Maier, W., 94, 95.Mairinger, F., 130.Maisel, G. W., 387.Maisch. W. G., 45.Maitlis. P. M., 195, 281,282.Maizels, M., 381, 383, 384,385, 392.Majer, P., 447.Majhofer, B., 268.Maj hofer-OreSEanin, B.,Majumder, A. K., 430,Majundar, S. G., 288.264.366.221.441 , 447.Majundar, S. K., 425.Makhanek, A. G., 67.Maki, A. H., 76.Maki, N., 160.Malatesta, L., 148, 158.Malcolm, G. N., 110.Malecki, J., 61.Maley, G. F., 397.Malhotra, S. S., 213.Malkin, T., 221.Mallik, K. L., 418.Malm, J. G., 158.Malmstadt, H. V., 442, 452.Malunowicz, I., 306.Malysz, D., 433.Malyvtina, T. M., 457.Malzacher, A., 432.Mamalis, P., 279.Mamlok, L., 312, 315.Manassen, J., 171.Mandel, M., 55, 57, 88.Mandeles, S., 428.Mandelkern, L., 110.Mandell, H.C., 136.Mandell, J. D., 429.Mandell, L., 323.Maneval, D. R., 456.Mangaraj, D., 112, 113.Mangini, A., 193.Mann, D. E., 47, 48, 49, 54,Mann, G. A., 47, 64.Mann, K. H., 26.Manners, D. J., 348, 349.Mannhardt, H. J., 310.Manning, D. I., 425.Manning, R. E., 280.Mannsfeldt, H.-G., 267.Mano, E. B., 420, 432.Manochkina, P. N., 187.Manogg, P., 95.Mansford, K. R. L., 261.Mantsavinos, R., 354, 357.Manuel, T. A., 145, 146,150, 234.Mao, I. I., 334.Marano, B., 302.Marcinkiewicz, S., 279.Marcinkowska, K., 448.Marco, G. J., 207.Marcus, R. A., 28,Maresh, C., 438.Margerum, D. W.. 413.Margolis, E.I., 451.Margrave, J. L., 11, 26, 45,Marianai, L., 262.Marion, L., 283, 287, 493.Markby, R., 144.Marker, L., 113.Markham, R., 297.Markin, R. T., 435.Markovits, I., 433.Markovskii, L. Y., 119.Markowitz, M. M., 461.Marks, N., 376.55, 123.247.Marks, R. E., 245.Marktscheffel, F., 200, 265.Marmur, J., 302, 356.Maron, S. H., 103.Maros, L., 449.Marquet, A., 312.Marquez, F., 267.Marsh, R . E., 491.Marshall, B. A., 333.Marshall, J. A., 254.Marshall, R., 96.Marshall, R. R., 424.Martell, A. E., 56.Martin, E. C., 430.Martin, F., 429.Martin, F. S., 115.Martin, H. J., 457.Martin, J. F., 10.Martin, N., 499.Martin, R. L., 62, 154, 163.Martinez, F. B., 418.Martuis, C., 408.Martjhova, L. A., 425.Maruta, S., 458.Marvin, D.A., 301.Maryott, A. A,, 61, 62.Marx, M., 315.Masamune, H., 329.Masamune, S., 289.Masamune, T., 293.Masi, I., 368.Masi, J. F., 22.Mason, E. A., 45.Mason, H. S., 92.Mason, J. A., 105.Mason, R., 465.Mason, S. F., 183, 269.Mason, S. G., 347.Massart, R., 437.Masschelein, W., 247.Massey, A. G., 121, 122.Massey, V., 398.Massey-Westropp, R. A.,Massicot, J., 432.Massoni, R., 347.Mateeva, N. G., 139.Mateles, R. I., 330, 458.Mateos, J. L., 313.Matheson, M. J., 74, 77.Mathieson, A. McL., 289,Mathieu, J., 313, 315.Mathur, A. P., 448.Mathur, H. H., 218.Matijevic, E., 86.Matlack, A. S., 108.Matsen, F. A., 93, 166.Matsuda, H., 100, 101.Matsuda, K., 345.Matsumoto, T., 325.Matsunaga, Y., 75.Matsuura, T., 252.Matsuyama, G., 445, 453.Matsuzaki, K., 349.Matthews, R.E. I?., 299.238.294, 494Matthias, G., 143.Matthies, P., 92.MaturovA, M., 284.Matuszko, A. J., 130.Matyska, B., 102.Matyukhina, L. G., 257.Mauer, F. A., 473.Maurey, J . R., 392.Mauli, R., 306.Maxted, E. B., 196.Maxwell, G. M., 367.May, H. E., 420.May, P. J., 307.Mayahi, R I . F., 179.Mayer, R., 331.Mayer, S. W., 25, 133.Maynard, J. C., 177, 435.Nayo, F. R., 170.Mayor, P. A., 309.Mayrick, R. G., 26.Mazor, L., 452.Mazur, P., 58.Mazur, Y., 307, 312, 313,Mazzanti, G., 124.Mazzucato, U., 167.Meadow, M., 421.Meadow, P. M., 395.Meakins, G. D., 306, 309.Meakins, R. J., 61.Meal, J. H., 49.Meath, J. A., 377.Meckenstock, K.-U., 424.Mechoulam, R., 328.Medrud, R.C., 475.Meek, D. W., 139.Meerwein, H., 264.Meetham, A. R., 12.hfegaw, H. D., 469, 486.Mehrotra, R. C., 445.Rleibohm, E. P. H., 154.Meiboom, S., 98.Meier, E., 452, 453.hleier, H., 350.Meier, J., 461.Meier, J. F., 103.Meier, W. M., 486.Meinert, H., 136, 242.Meinwald, J., 245, 271, 274.Meisel, T., 452.Meisels, A., 258.Meisenheimer, R. G., 63.Rleisinger, M. A. P., 199.Meister, A. G., 48.Meisters, A., 217.Meixner, J., 92.Melby, L. R., 207.Melera, A., 248, 258.Melichar, O., 272.Melrose, G. J. H., 252.Meltzer, H. L., 379.Melville, H. W., 73, 96.Melvin, E. H., 217.Melvin, P. H., 256.Mendelson, R. A., 105.Mendicino, J. F., 336.323.INDEX OF AUTHORS’ NAMEMenis, O., 425, 426.Menke, H., 426.Menke, M.R., 425, 426.Menzies, A. C., 458.Mercer, D., 436.Meredith, C. C., 56.Meredith, E. A., 456.Merhyi, R. G., 148.Mi.resz, O., 335.Meriel, P., 467.Mkring, J., 344.Merrill, S. H., 298.Merritt, C., jun., 438.Merritt, C. R., 392.Merritt, J. A., 49.Mertcn, U., 25.Meselson, M., 302.Meshcherijakov, A. P., 9,Messerly, J. F., 12.Messerly, J. P., 438.Metesies, W., 128.Meth-Cohn, O., 458.Metlesics, W., 148.Metz, H., 310.Rletzger, L. C., 128.Meville, D. B., 260.Meyer, K., 327, 328.Meyer, M. W., 185.Meyerhof, O., 391.Meyerhoff, G., 106, 107.Meyers, M. D., 160.Meperson, S., 227.Meystre, C., 310, 317.Meyer zu Reckendorf, W.,Mez, H. C., 149.Mhala, M. M., 181.Rlian, ,4. J., 349, 350.Michalov, J., 487.Micheel, F., 343, 345.Michel, G., 217.Michel, K.-W., 36.hfichels, J.G., 270.hlichelson, A. M., 298, 303,Mihailovid, Ill. L., 317, 318.Mijovic, M. P. V., 268.Mikhailov, G. RI., 468.Mikhailov, G. P., 112.Mikhalevich, K. N., 157.Mikheeva, V. I., 124, 153.Miksic, M. G., 488.Milas, N. A., 160.Milazzo, G., 453.Miley, J. W., 387.Millard, M., 132.Milledge, H. J., 469, 479,Millen, D. J., 48, 55.Miller, B. S., 70.Miller, C. D., 224.Miller, F. A., 115.Miller, G. A., 238.Miller, I. T., 191.Miller, J., 190.238.436.304, 353.491.527Miller, J. J., 120, 121.Miller, J. R., 161.Miller, J. W., 445.Miller, P., 377.Miller, R . G., 20, 192, 227.Miller, R. L., 108.Miller, R. S., 348.Miller, W.T., jun., 174,Mills, G. T., 297, 351.Mills, I. M., 49, 50, 51, 52,Itlills, J. F. D., 493.Mills, J . S., 258, 312, 313.Mills, 0. S., 493.Millward, B. B., 279.Milne, T. A., 25.Milner, G. W. C., 412, 413.Milner, 0. I., 440, 451, 453.RIinaard, N. G., 242.Minakani, S., 398.Minato, H., 251.Minczewski, J . , 444.Ming G. Lai, 440.Mingazin, T. A., 485.Minton, R. G., 172.Mironov, A., 251.Rlironov, V. F., 55.Mirumyants, S. O., 41.Missa, L., 437,Mitchell, D. L., 200.Mitchell, P., 380.Mitcherling, B., 130.Mitra, A. K.. 338.Mitra, R. B., 251.Mitra, S. S., 194.Mitscher, B. J., 305.Mitscher, L. A., 305.Mitsuhashi, H., 324.Mitsui, T., 414.Miura, K., 301.Miwa, T., 343.Miyake, S., 435.Miyano, S., 196.Miyugawa, I., 72.Mizukami, S., 290, 452.Mizuno, Y., 53.Mizunov, J., 478.Modiano, A,, 234.Mobius, L., 191.Modritzer, K., 131.Mdler, C.K., 469, 476.Moeller, C. W., 62.Moeller, T., 130, 131, 139.Monch, J., 245.Moffatt, S. J., 256.Mohammed, Y. S., 344.Mohaupt, G., 158.Moiseer, I. I., 147, 170.Moiseeva, L. M., 439.Moizhes, M. Y., 452.Moki, M., 162.Mole, T., 240, 242.Molotkovsky, J. G., 200.Momose, T., 300.Moneham, P. K., 166.207.59528 INDEX OF AUTHORS’ NAMES.Monk, C . B., 83.Monod, J., 391, 394.Montgomery, H., 162.Montgomery, H. A. C., 439.Montgomery, L. K., 192,Moody, G. J., 333.Mooney, E. F., 121.&looney, R. W., 477.Moore, B., 76, 117, 288.Moore, C. E., 440.Moore. D. W., 147.Moore, F. H., 164.Moore, F.L., 425, 426.Moore, G. E., 59.Moore, L. D., jun., 105.Moore, P. T., 171, 248.Moore, R. H., 331.Moore, R. N., 254.Moore, S., 500.Moore, W. J., 163,Moore, W. R., 171, 218.Mooser, E., 472.Mootoo, B. S., 291.Moraglio, G., 105, 110, 112.Moraw, R., 96.hforehead, F. F., 109.Morgan, C. R., 173.Morgan, E., 44.Morgan, F. R., 413.Morgan, H. E., 380.Morgan, K. J., 292.Morgan, L. R., 270.Morgan, R. L., 207, 312.Mori, T., 57.Moriarty, R. M., 307.Moriya, M., 349.Morikawa, I., 398.Morino, Y., 51, 55.Morita, K., 312.Morley, H. V., 280.Morley, K. A., 464, 490.Morokuma, K., 184.Morozov, A. A., 428.Morozova, M. P., 22.Morris, A., 340.Morris, D., 55.Morris, D. F. C., 441.Morris, J. R., 193.Morris, L. J., 217.Morris, R.O., 177, 190.Morrissette, R. A., 439.Morrison, G. A., 235.Morrison, G. H., 423, 454.Morrison, J. D., 487.Morrison, J. L., 347.Morrison, R. A., 360.Morron, J. C., 479.Morrow, S. I., 128.Morschel, H.. 264.Mortimer, C. T., 15, 20,Morton, J. R., 48, 55.Morton, R. A., 216, 402,Mosettig, E., 255, 323.241.22.403.Nosevitsky, Ri. I., 303.niosher, R. A., 202.hloskowitz, A., 443.Moss, C., 23.Moss, K. C., 122.Moss, R. A., 138.RIOSS, T. S., 65.Mostardini, E., 234.Mothes, K., 282.Mould, H. M., 46, 47.AIoulden, H. N., 192.bioule, D.. 48.Moulton, K. H., 393.Moulton, W. G., 71.RIoureu, H., 16.Mousseron, M., 216.Mousseron-Canet, M., 215,Moustafa, A. S., 446, 447.Moyle, M., 254.hfuller, A., 96.Miiller, E., 243.11Iiiller, H., 125, 155.blueller, H.F., 429.hliiller, %I., 321.hliiller, R. H., 412.Miiller Uri, G., 453.hIuetterties,_E. L., 21, 119,Muhn, G. A., 80.Muirhead, H., 495.Mukawa, F., 313.Mukhedkav, A. J., 64.Mukherjee, A. K., 441.Mukherjee, L. M., 87.hlulholland, ’1.. P. C., 256.Mulle, H., 478.Muller, A., 96.Muller, G., 317.Muller, N., 48, 126.Muller, R., 500.Mullhaupt, J. T., 129.Mulliken, R. S., 44, 184.Mullins, L. J., 371, 381.hfuntz, J. A., 333.Muraca, R. F., 444.Murai, K.. 229.Murashi, S., 108.Murdoch, H. D., 266.Murphy, C. B., 461.Murphy, E. A., 431.Murray, K. A., 163.Murray, K. E., 219, 220.Murray, K. J., 119, 196.Murray, I,. J., 119, 196.Murray, M. A., 199.Murray, R. W., 175, 230.Murty, B.V. R., 490.Musgrave, 0. C., 274.Mussa, C., 107.Mutschler, E., 432.Muxfeldt, H., 229.Myao-Syu Li, 22.Myers, R. J., 55.nfyers, 0. E., 23.n m . o., 252.216.133, 139.hlyhre, D. V., 340.hlyhre, P. C., 188.Nabar, G. M., 347.Nabi, S. N., 134, 223.Nabney, J., 235, 277.Nace, H. R., 308.Nachmansohn, D., 373.Nadeau, H. G., 459.Nasanen, R., 86.Naffa, P., 335.Nagahama, S . , 252.Nagarajaiah, H. S., 160.Nagata, C., 184.Nagata, W., 319.Nager, M., 419.Nagorsen, G., 464.Nagyvari, J.. 289.Nahringbauer, G., 493.Nakagawa, Y., 290.Nakajima, N., 103.Nakamura, A., 145, 146,Nakamura, &I., 330, 343.Nakamura, S., 343.Nakamura, Y., 51.Nakane, R., 112.Nakanishi, S., 207, 312.Nakano, T., 306.Naldini, L., 158.Nametkin, N.S., 55.Nancollas, G. H., 79, 82,Naoi-Tada, hI., 301.Naqvi. N., 194.Narath, A,, 131.Narayanan, C. R., 292.Nardelli, M., 480, 481.Nascimento, J. M., 324.Nasielski, J., 189.Nason, A., 401, 402.Nassar, R. F., 262.Nast, R., 148.Natelson, S., 432.Nathan, A. H., 312.Nathans, R., 467.Natoli, R., 169.Natta, G., 108, 142, 475.Naudet, M., 218.Nauman, R. V., 458.Nauta, W. T., 226.Naves, Y.-R., 248, 264.Naville, G., 184.Navita, S., 48.Nawar, W. W., 435.Nayak, U. G., 218.Nayler, J. H. C., 261.Neely, E. E., 438.Neely, W. B., 346.Neeman, M., 203, 293, 314.Nefkens, G. H. L., 205.NehmC, M., 160, 209.Nehring, K., 451.Neiderhiser, D. H., 307.Neihof, R., 432.Nelson, B. N., 412.233, 234.87INDEX OF AUTHORS’ NAMES.529Nelson, G. J., 427.Nelson, N. A., 314.Nelson, R. A., 16, 18.Nelson, S. M., 61.Nelson, T., 23.NEmeEkovA, A., 284.Nenitzescu, C. D., 222, 272.Neporent, B. S., 41.Nerdel, F., 64.Nerheim, A. G., 437.Neri, R., 312.Neronova, N. N., 466.Nesmeyanov, A. N., 155,185, 233.Ness, P., 154.Ness, R. K., 294.Nethercot, A. H., 58.Nettleton, H. R., 275.Neubauer, D., 134.Neufeld, H. A., 398.Neukom, H., 330, 346, 350.Neumiiller, 0 . - A . , 308.Neuss, N., 288.Neuville, C., 308.Neuwald, F., 498.Newbold, G. T., 266.Newkirk, A. E., 118, 460,Newlands, M. J., 127.Newman, A. C. D., 61.Newman, C., 48.Newman, H., 256.Newman, L., 164.Newman, M. S., 197, 199.Newman, S., 104.Newnham, I. E., 155.Newnham, R.E., 486.Newton, G. G. F., 268.Newton, T. W., 141.Nichols, G. M., 70.Nichols, L. D., 150.Nicholson, G. R., 10, 11.Nicholson, J. P., 108.Nicholson, R. T., 312.Nickerson, R. G., 262.Nickon, A., 308.Nicksic, S. W., 450.Nickson, P. G., 23.Nicolson, A., 254, 255.Niederl, J. B., 419.Niedermaier, T., 414.Niederpriim, H., 127.Niegisch, W. D., 109.Nielsen, A. H., 48.Nielsen, H. H., 46, 52.Nielsen, J. T., 45.Nielsen, L. E., 108.Niesel, W., 92.Nifant’ev, E. E., 241.Nigam, H. L., 143, 444.Nigam, V. N., 332, 345.Nightingale, E. R., jun.,Nikitin, 0. T., 26.Nikitona, T. V., 233.Nilrkari, T., 437.472.442.Nilsson, S. K., 448.Nimmo, C. C., 437, 438.Nimz, H., 340.Nisel’son, L. A., 156.Nishie, I<., 373.Nishikawa, H., 145.Nishimura, S., 301.Nishioka, A., 102.Nishioka, I., 325.Nitta, I., 108, 490.Nitz-Litzow, D., 408.Nison, H.L., 501.Noe, J., 419, 420.Nijth, H., 86, 119, 149, 197.Nolan, G., 89.Nolle, A. W., 113.Noller, C. R., 258.Noltes. J. G., 128.NominC, G., 310, 318.Noonan, T. R., 381.Nooteboom, G., 137.Nord, F. F., 237.Nordin, P., 348.Nordman, C. E., 116, 119,120, 487.Norgard, D. W., 215.Norin, T., 252.Norris, J. A., 47.Norris, K. H., 457.Norris, 3’1. S., 429.Norris, N. R., 358.Norris, W. G., 44.Norrish, R. G. W., 41.North, A. C. T., 495, 501.Northcote, D. H., 360.Noszkb, L., 248.Nov&k, L., 286.Novikov, G. I., 22.Novikov, M. M., 44.Novoselova, -4. V., 118.Novotnjl, L., 251, 289.Novozhilova, K.I., 452.Nowacki, W., 466.Noyce, D. S., 12, 172, 244,Noyes, R. N., 96.Nozaki, H., 252.Nozoe, T., 225, 230.Nurnberg, H. W., 101.Numoto, I<., 452.Nunn, E. I<., 117.Nussbaum, A. L., 308, 311,Nussim, M., 198, 313.Nutile, A. N., 308.Nutt, C . W., 64.Nuttall, R. H., 121.Nuttall, R. L., 16.Nyburg, S. C., 469, 493.Nyholm, R. S., 62, 141,143, 152, 157, 158, 161.Nyman, C. J., 83.Oaks, D. Rf., jun., 459.Obara, H., 280.Oberhansli, P., 216.247.316, 323.Oberster, A. E., 202.O’Brien, S., 275.Obtemperanskaya, S. I.,Ochiai, E., 195.Ochoa, S., 359.Ochsner, P., 264.Ockewitz, K., 267.O’Connell, J. J., 56.O’Connor, A., 109.O’Connor, J. G., 429.O’Connor, K. T., 343.Odajima, A., 112.ofele, K., 142, 144.ohm, 0.E., 349.Olin, .4., 87.Oelschlagel, X., 267.Ordogh, M., 412.Oesterling, R. E., 192.Ozeris, S., 430.Ofner, A.. 216.Oftedahl, M. L., 342.Ogawa, H., 343.Ogg, R. A., 98.Ogston, A. G., 388.Ogur, M., 296.Ohlberg, S. nl., 476.Ohloff, G., 243.Ohno, RI., 249.Ohno, N., 240.Oita, I. J., 452.Oka, S., 99.Oka, T., 55.Okabe, H., 37.Okamura, S., 102.Okanishi, T., 323.Okano, K., 107.Okawara, R., 128.Okaya, Y., 468, 493, 494.Okazaki, A., 476.Okazaki, R., 297.Okazaki, T., 297.Okinaka, J., 101.O’Konski, C. T., 65.Oksengorn, B., 52.Okunuki, K., 395, 399.Olah, G. A., 163, 204.Olander, C. J., 26.Oldenburg, E. B., 126.Oldham. K. G., 181.Olenovich, N. L., 428.Olivares, E., 313.Oliver, J. O., 384.Olivets, E.P., 308, 312,316, 323, 325.Ollis, W. D., 229, 235, 238,279, 280.Olovsson, I., 129, 133, 473.Olsen, C. E., 485.Olsen, E. D., 434.Olson, A. R., 82.Olson, E. C., 452.O’Malley, E., 385.O’Meara, D., 334.Onak, T. P., 288.Ondetti, M. A., 287.453530 INDEX OF AUTHORS’ NAMES.O’Neal, M. J., 305.Onsager, L., 91.Onyon, P. F., 170.Onyszchuk, M., 121,Ookuni, J., 167.Oosting, M., 423.Opara-Kubinska, Z., 300.Opidnska-Blauth, J., 422.Oppegard, A. L., 133.Oppelt, J. C., 224.Oppenheim, I., 104.Ordronneau, C., 168, 230.Orgel, L. E., 68, 115, 137,Origoni, V. E., 315.Origlio, G. F., 112.Orii, Y., 399.Orr, A. A., 434.Orr, D. E., 294.Orton, J. W., 68, 69.Orttmann, H., 206.Orville-Thomas, W. J., 67.Osawa, S., 298, 299, 302.Osbond, J.M., 217.Osborn, E. M., 457.Osiecki, J., 248.Osipov, 0. A., 139.Ossowski, B., 430.Oster, G., 446.Osterhout, W. J. V., 391.O’Sullivan, D. G., 428.O’Sullivan, W. I., 272.Oswald, H. R., 475.Otaka, E., 299, 302.Oth, A., 302.Ott, N., 191, 226.Ott, H., 345.Ottendorfer, L., 451.Otter, R. J., 64, 83.Otto, R. J. A., 130.Otvos, L., 248.Oubridge, J. V., 88, 132.Ouchinnikov, Iu. A., 229.Oudemans, G. J., 62.Ouderkirk, J. T., 271.Oughton, B. M., 494.Oughton, J. F.. 307.Ourisson, G., 63, 252, 256,Ovakimyan, G. B., 431.Ovcharenko, I. E., 44.Ovchinnikov, Yu. V., 113.Ovenall, D. W., 71, 73.Overberger, C. G., 243.Overend, J., 47, 48, 49, 51.Overend, W. G., 329, 333,Overton, K. H., 237, 242,Owen, L.N., 199, 336.Owens, B. B., 25.Owens, E. G., 11, 447.Owings, F. F., 315.Owston, P. G., 145, 153,Oxford, A. E., 344.138, 144, 145, 156.313.335, 341.250.483.Oxman, M., 237.Oyama, Y., 324.Oyowa, T., 359.Ozawa, K., 53.Paabo, M.. 84.Pachter, I. J., 285.Packham, D. I., 24.Pacsu, E., 341.Paddock, N. L., 15, 130.Padgett, A., 45.Paetzold, R., 135.Page, A. C., 403.Page, F. M., 91, 93.Page, L. B., 388.Pai, P. R., 249, 293.Paine, D. H., 130.Paine, R. M., 484.Painter, T. J., 346, 349,350.Pake, G. E., 77.Pal, B. K., 430.Palade, G. E., 396.PalAgyi, T., 428, 430.Palevsky, H., 470.Pallaud, R., 202.Pallihre, M., 429.Palm, C., 146.Palmer, D. R., 276.Palmer, J., 98.Palmer, J. W., 141.Palmer, K., 287.Palmer, R.C., 435.Panattoni, C., 161, 163,Panchenkov, G. Bf., 55.Pande, C. S., 447.Pande, K. C., 189.Pandit, A. L., 229.Pandit, U. K., 180.Pandya, K. P., 403.Paner, M., 191.Pankova, M., 176.Pannetier, G., 44.Pant, L. M., 491.Pantonin, J . A., 155.Panzer, R. E., 154.Paoletti, A., 476.Paoletti, P., 23, 138.Papadopoulos, N. M., 429.Papadopoulus, S., 279.Papee, H. M., 20.Pappas, J. J., 242.Pappius, H. M., 383, 386,Pappo, R., 315.Paramonova, V. I., 159.Parham, W. E., 175, 274.Park, C. R., 380.Park, J. D., 14.Park, T. O., 413.Parker, A. J., 190.Parker, C. A., 423, 485.Parker, C. O., 128.Parker, F. S., 331.Parker, R. E., 176, 178.Parkins, G. M., 57.480.387.Parnes, 2. N., 201.Parpiev, N.A., 481.Parris, C. L., 225.Parrish, R. G., 496.Parry, E. P., 453.Parry, R. W., 56.Parshall, G. W., 129.Parsons, D. S., 387.Parsons, M. A., 338.Parsons, T., 122.Partch, R., 184.Partington, J . R., 64.Partlow, E. V., 349.Partridge, J. M., 153.Pasqualini, J. R., 428.Pasquon, I., 108.PAssera, P., 440.Pasternak, R. A., 476.Pasto, D. J., 230.Pasztor, L., 424.Patai, S., 174.Patat, F., 107.PAtek, V., 452.Patel, C. C., 439.Paterson, A. R. P., 361.Paterson, W. G., 121.Patnaik, D., 153.Patrick, C. R.. 269.Patrick, J., 419.Patrie, M., 153.Patterson, A., 79.Patterson, A. L., 116, 487.Patterson, A. M., 259.Patterson, C. S., 88.Patwardhan, V. M., 448.Paufler, R. M., 232, 246.Paul, J., 357, 424.Paul, M.A., 181.Paulik, F. E., 129.Paulik, P., 461.Paulin, D., 127.Paulin, P., 417.Pauling, C., 155.Pauling, L., 115, 498.Pauling, P., 157.Paulsen, H., 163.Pauncz, R., 184, 228.Pauson, P. L., 143, 234.PavlikovA, M., 445.Pavlov, P. V., 463.Pavla, J., 431.Payne, G. B., 202.Payne, S. T., 428.Payne, T. A., 328.Pazur, J. H., 297.Peacock, R. D., 62, 136,137, 144, 156, 157, 158,160.Peacocke, A. R., 302.Peak, D. A., 269.Peaker, F. W., 106, 412.Pearl, I. A., 420.Pearson, D. L., 166.Pearson, F. G., 108.Pearson, R. G., 94, 98, 141,142INDEX OF AUTHORS’ NAMES. 53 1Pearson, W. B., 472.Pease, W. F., 423.Peat, S., 346.Pedar, M., 439.Pechanec, V., 450.Pechet, M. M., 203, 316.Pedersen, B., 478.Pedersen, C., 294, 340.Pederson, B.F., 140.Pedley, J. B., 24.Peeling, M. G., 189.Peiser, H. S., 473.Peizulaev, S. I., 454.Pelah, I., 470.Pelizza, G., 262.Peller, L., 91.Pelletier, S. W., 291.Peltzer, H., 31.Pendergrast, J., 461.Pendleton, J. F., 240.Penefsky, H., 408.Penfold, B. R., 125, 478,Penna-Franca, E., 373.Pennella, F., 150.Penneman, R. A., 161.Penneman, R. H., 82.Pennington, R. E., 12.Pennock, J. F., 216, 403.Pepinsky, R., 468, 493,Peraldo, M., 143.Percival, E., 347, 349.Peregud, E. A., 456.Perelman, M., 311.Perevalova, E. G., 233.Perez-Ossorio, R., 11.Pergiel, F. Y., 18, 20.Perkins, H. R., 342.Perkins, P. G., 23, 121, 125.Per Kokeritz, 55.Perlin, A. S., 337, 338.Perlman, D., 260.Perlman, P., 312.Perlmu tter-Hayman, B.,Peron, F.G., 297.Perrin, D. D., 87, 137, 162,Perry, D. D., 128.Perry, M. B., 340, 350.Perry, R., 91.Perry, S. G., 180.Persky, A., 333.Person, W. B., 52, 187.Perutz, M. F., 495, 496,Pesez, M., 450, 457.Peshkova, V. M., 79, 137.Pesis, A. S., 441.Pester, R., 274.Peter, B., 86.Peter, M., 69.Peterlin, A., 106, 109.Peters, C. R., 120.Peters, D., 183.488.494.92, 333.194.499.Peters, R. (Sir), 217.Petersen, D. H., 54.Petersen, H. J., 166.Petersen, J. M., 205.Petersen, Q. R., 307.Petersen, H. C., 206.Peterson, D. J., 127.Petersen, J., 494.Peterson, P. E., 244.Peterson, R., 240.Petit, R., 168, 195.Petitpas, T., 344.Petrauskas, A. A., 95.Petrov, A. D., 185, 238.Petrow, V., 201, 306, 310,Petru, F., 254.Petry, R.C., 129.Petter, P. J., 66.Pettit, G. R., 200.Petty, W. L., 212.Petzold, E. N., 214.Petzoldt, K., 234.Peurifoy, P. V., 419.Pevzner, M. S., 23.Peyron, L., 429.Pickart, S. J., 467, 476.Pickworth, J ., 494.Piekara, A., 60, 61.Piekarski, C., 479.Pienaar, W. J., 454.Pierce, L., 48, 54, 55.Pierce, T. B., 458.Piercy, J. E., 95.Pierdet, -4., 310, 318.Pietsch, R., 439.Piette, L. H., 76, 98.Pigman, W., 343.Pigon, A., 370.Pike, J. E., 308, 317, 319.Pilbeam, A., 265.Piler, F. L., 193.Pillar, C., 8.Pimental, G. C., 116.Pinchas, S., 46.Pincock, R. E., 242.Pincus, J. R., 432.Pinder, A. R., 280.Pines, H., 202.Pinhey, J. T., 252.Pinkus, J. L., 491.Pinson, R., 312.Piozzi, F., 276.Pirtea, T.I., 441.Pitochelli, A. R , 121.Pittet, A. O., 330.Pitzer, T<. S., 12, 57.Pfab, W., 148.Pfann, W. G., 423.Pfau, A., 430.Pfau, H., 267.Pfeifer, V., 426.Pfluger, C. E., 124.Pfohl, W., 125.Phang. S. E., 415.Philcox, H. J., 453.313.Philips, G. O., 333.Phillips, A. T., 348.Phillips, D. C., 491, 495,Phillips, D. J., 161.Phillips, J. N., 260.Phillips, L. V., 223.Phillips, W. D., 75.Planchon, M., 189.Plane, R. A., 65.Plane, R. H., 83.Platonova, T. F., 291.Pledger, H., jun., 212.Plesske, K., 234.Plettinger, H. A., 487.Plieth, K., 481.Plimmer, J. R., 260.Plumb, J. B., 127.Plumlee, M. P., 415.Plyler, E. K., 43, 46.Pocker, Y., 83, 166, 167,169, 171, 172, 173, 174,176, 179.496.Pocohiari, F., 368.Podanj., V., 447.PodeSva, C., 279.Podlaha, J., 156.Pohl, H.A., 57.Pohlke, R., 192, 241.Pohloudek-Fabini, R., 431.Pohoryles, L. A., 181, 339.Poiget, G., 323.Poittevia, A., 317.Pokorn9, J., 456.Pokraka, S. I., 241.Polak, H. L., 445.Polanyi, J. C., 41.Pollard, C. J., 402.Polgar, N., 217.Polis, B. D., 408.Polo, S. R., 48.Pombo, M. M., 173.Pontineu, R. E., 70.Pontis, H. G., 297.Pontremoli, S., 332.Pope, A., 375, 391.Popelak, A., 290.PopiSil, Z., 102.Popjhk, G., 215, 305.Pople, J. A., 27, 53, 57, 64,Popov, M. M., 22.Popova, L. K., 454.Popper, T. L., 249, 308.Porai-Koshits, M. A., 161,480, 481.Porte, A. L., 487.Porter, G., 96.Porter, J. J., 175.Porter, J. W., 215.Porter, R. F., 24, 25, 117.Porter, R.S., 113.Porto, S. P. S., 47.Post, B., 473, 487, 488.Post, R. L., 392.Potter, R. S., 429.65532 INDEX OF AUTHORS’ NAMEPotter, V. R., 354, 357,358, 361, 429.Potters, M. L., 466.Potts, H., 288.Poulson, R. E., 95, 437.Pover, W. F. R., 424.Powell, A. S., 456.Powell, D. B., 145, 350.Powell, J. E., 443.Powell, R. E., 31.Powers, D. D., 267.Powers, R. M., 459.Powles, J. G., 61, 112.Praag, D. V., 295.Pradham, S. K., 258.Prager, R. H., 284.Prankerd, T. A. J., 389.Prat, H., 19.Pratt, L., 146, 149.Pratt, S. A., 111, 443.Prelog, V., 216, 222, 229.Preisler, E., 155.Preiss, J., 361.Preston, B. N., 302.Pretorius, V., 436.Prey, V., 223, 336, 339.Price, A., 83.Price, A. H., 61.Price, E., 83, 167.Price, F.P., 109.Price, H. A., 451.Price, J. W., 432.Price, R., 280.Price, W. C., 43, 46, 47, 84.Priddle, J. E., 330, 339,435.Pridham, J. B., 344, 350.Prieto, A., 412.Prince, E., 463.Prince, R. H., 92, 128.Pristavka, D., 448.Pritchard, H. O., 36, 75.* Priyadaranjan, RBy, 440.Proctor, J. E., 130.Profft, E., 265.Prokhorov, A. M., 48, 54.Prophet, H., 125.Prosen, E. J., 9, 18, 20, 22.Prosen, R. J., 494.ProStenik, &I., 221.Protiva, M., 286.Prue, J. E., 64, 82, 83, 86,Pruett, R. L., 142.Pruvot, E., 456.Pryde, E. H., 202, 219.Przheval’skii, E. S., 439.Przybylska, M., 493.Pszonicki, L., 454.Puckett, J. E.. 451.Piischel, R., 444, 453.Pugh, H., 134.Puisieux, F., 288.Pulkkinen, E., 147.Pullman, M. E., 408.Pumphrey, A.M., 402, 403,160.409.Purcell, J. R., 436.Purlee, E. L., 98.Purnachandra Rao, B., 66.Purpura, D. P., 369.Purushothamen, K. K.,Purves, C. B., 349.Puterbaugh, W. H., 205.Puttnam, N. A., 185.Fyszora, H., 121.Quackenbush, F. W., 214,Quartermain, P. G., 445.Quattrone, J , J., jun., 438.Queen, A., 261.Quilico, A., 276.Quimby, 0. Y., 131.Quinkert, G., 205, 242, 321.Quinn, H. W., 163.Quinn, R. A., 202, 242.Quitt, P., 255.Raab, R. E., 57.Rabaud, H., 490.Rabi, I. I., 67.Rabideau, S. W., 141.Rabinovitch, B. S., 28, 31,33, 35, 36, 37, 38, 39, 41.Rabinovitz, M., 273.Rabinowitch, E., 96.Rabjohn, N., 223.Rachor, J., 287.Racker, E., 408.Radding, C. M., 304, 356.Kadmacher, W., 450.Raker, I<. O., 425.Raffauf, R.F., 285.Kagade, I. S., 293.Raimbault, C., 418.Rains, T. C., 426.Raistrick, H., 235.Rajadurai. S., 249, 293.Rajagopalan, S., 292, 293.Rajappa, S., 286, 293.RajSner, M., 286.Rekhit, S., 325.Rall, T. W., 297.Ramachandran, G. N., 464.Ramakrishna, R. S., 457.Ramakrishna, V., 415.Raman, S., 464.Rambidi, N. G., 131.Ramette, R., 88.Ramsay, D. A., 43, 44.Ramsey, N. F., 62.Ramsperger, H. C., 28.Ramstad, E., 282, 326.Ranachandran, P. K., 253.Ranby, B. G., 109, 110.Rand, S. J., 96, 187.Randall, J. J.. 1S9.Randall, T., 23.Randle, P. J., 380.Rank, D. H., 46, 47, 52.Kao, A. S., 250.249.215.Rao, B. L., 219.Rao, K. N., 46, 85.Rao, M. V., 291.Rao, P. T., 44.Rao, U. R., 285.Raoult, G., 65.Raphael, R.A., 209, 224,237, 242, 254, 274, 305.Rapoport, H., 229, 282,284, 288.Rappoldt, M. P., 322.Rapport, M. M., 431.Rasburn, J. W.. 244.Rasmussen, S. E., 481.Rassat, A., 63, 252.Ratts, K. W., 207.Rauhut, M. M., 226.Rausch, M. D., 234.Kauss, J., 213.Ravenscroft, hI. J.. 425.Rawitscher, hI., 19.Ray, A. E., 465.Ray, J. D., 98.Ray, N. H., 133.Raynolds, S., 269.Read, R. I., 38.Read, T. O., 207.Readshaw, R. L., 205.Rebane, T. K., 66.Rebbe, 0. H., 381.Rebenstorf, M. R., 308.Reckhard, H., 154.Recourt, J. H., 305.Redcliffe, A. H., 220.Reddi, K. I<., 301.Reddy, G. K. N., 152.Reddy, S. P., 44.Redfearn. E. R., 402, 403,Redies, M. F., 49.Redpath, J., 266.Ree, T., 98.Reed, R. I., 255, 346.Reed, W. R., 130.Rees, C.W., 333.Rees, D., 328.Rees, D. I., 446.Rees, W. T., 455.Reese, C . B., 295.Reetz, T., 129.Reeve, W., 206.Reeves, L. W., 247.Rehm, W. S., 387.Reich, F., 277.Reich, R., 267.Reichard, P., 351, 358.Reichle, W. T., 150.Rcichstein, T., 306, 312,324, 326, 327, 328, 329.Reiding, D. J., 226.Reif, F., 67.Reif, L., 185.Reiff, L. P., 258.Reilley, C. N., 443, 447.Reilly, C . A., 81.Reimann, I$., 312.404, 409INDEX OF AUTHORS’ NAMES. 533Rein, J . E., 426, 427.Reinert, K., 125.Reinheimer, J , D., 190.Reinmuth, O., 203.Reinwein, D., 380.Reischl, A., 272.Reisman, A., 155, 444, 461.Reisse, J., 247.Reist, E. J., 340, 342.Reitz, I). C., 79.Reitz, L. L., 415.Rembarz, G., 335.Remers, W. A., 211.Remington, M., 385, 392.Remmert, L.F., 408.Remy, H., 132.Reneker, D. H., 109.Renner, H., 47, 64.Renner, J., 273.Rennie, R., 335.Renold, W., 230.Renouf, T. J., 484.Renshaw, A., 386, 388.Rentzapis, P., 25.Repetto Jimhez, M., 337.Replogle, L. L., 231.RCrat, C., 491.Rerick, M. N., 199.Reschke, R. F., 438.Ressler, N., 433.Reuben, B. G., 30.Reuter, B., 163.Reynolds, J. J ., 283.Reznitskii, L. A., 18.Rhind-Tutt, A. J., 174.Rhinesmith, H. S., 499.Ribas, I., 283.Ribeiro, O., 285.Ribner, A , , 419.Rice, F. O., 34.Rice, 0. K., 28.Rice, S. A., 356.Rich, A., 255, 496.Richards, D. H., 82.Richards, F. M., 482.Richards, G. N., 334.Richards, J., 354, 355.Richards, J. H., 152, 233,Richards, R. E., 81, 139,Richardson, A.C., 338.Richardson, E. A., 84.Richardson, E. H., 48.Richardson, I;. D., 25, 157.Richert, H., 134.Richey, H. G., jun., 167.Richmond, M. H., 228.Richter, E., 277.Richter, H., 131.Richtmyer, N. K., 332.Rickards, R. W., 238,274.Ridd, J. H., 194, 195, 276.Riddle, J. M., 121.Rieche, A., 225.Iiied, W., 224.238.220, 276.Rieder, S. V., 342.Riemen, W., III., 434.Riemer, J., 206.Riemschneider, R., 234.Riemersma, J. C., 431.Riesenberg, H., 95.Riggs, A. F., 500.Riley, D. P., 501.Rinehart, K. L., jun., 238,Rinehart, R. W., 53.Ringertz, N. R., 351.Ringler, R. L., 398.Ringold, H. J., 306, 312,Riniker, B., 251.Ripley, R. A., 230.Ripoll, J.-L., 239.Ripphahn, J., 324.Riseman, J., 106.Ritchie, E., 284.Rivest, R., 139.Rizk, H.A., 66.Robberman, Zh. N., 102.Robert, H., 213.Robert, J., 323.Roberti, D. M., 61.Roberts, A., 200.Roberts, D. E., 110.Roberts, E., 368, 373.Roberts, E. M., 77.Roberts, G. P., 346.Roberts, H. L., 23, 133.Roberts, J. C., 279.Roberts, J. D., 81, 98, 173,176, 191, 192, 240, 241,305.Roberts, J . E., 134.Roberts, J . G., 346.Roberts, K. H., 450.Roberts, P. J . P., 348.Robertson, D. N., 271.Robertson, G. I., 450.Robertson, J. D., 370.Robertson, J. H., 494.Robertson, J , M., 252, 258,285, 469, 487, 489, 493,494.Robertson, J. S., 386.Robertson, P. W., 187.Robertson, R. E., 176,183.Robertson, R. N., 380.Robinson, A. E., 430.Robinson, B., 275.Robinson, C. H., 312.Robinson, D. W., 48, 113.Robinson, E.A., 85.Robinson, G., 493.Robinson, J. R., 380, 387.Robinson, J. W., 452, 454.Robinson, K. W., 288.Robinson, &I., 393.Robinson, M. J. T., 279.Robinson, P. L., 115, 160.Robinson, (Sir) Robert,266.317.216, 275, 288.Robinson, R. A., 84.Robinson, R. J., 367.Robinson, T. A., 440.Rocek, J., 170.Rochelmeyer, H., 432.Rochow, E. G., 128.Rockland, L. B., 415.Rodden, C. J., 412.Rodewald, H. J., 26.Rodger, M. N., 254.Rodgman, A., 223.Rodley, G. A., 131.Rodnight, R., 367.Romgens, M. J. H., 466.Roffio, S., 82.Rogalski, W., 229.Rogers, E. F., 291.Rogers, H. J., 342.Rogers, L. B., 436.Rogers, N. A. J., 254.Rogers, R. N., 77, 415, 453,Roginski, E., 196.Rogowski, F., 134.Rohr, O., 8.Roig, A., 104, 105.Rokowski, A., 93.Rolfe, R., 302.Rolih, R.J., 228.Rollett, J. S., 494.Rollier, M. A., 123.Romafiuk, hl., 249.Romeo, A., 325.Romers, C., 490.Rarmming, C., 483.Romo, J., 311.Rooda, R. W., 283.Roof, R. B., 455.Rooney, J. J., 26.Roper, J . N., jun., 436.Ropp, G. A., 87, 183.Ropp, R. C., 477.Rose, H.-J., 261.Roseman, S., 298, 351.Rosemeyer, M. A., 501.Rosen, W. E., 305.Rosenbaum, J., 166.Rosenberg, A., 377, 388.Rosenberg, A. F., 427.Rosenberg, B. H., 302.Rosenberg, S. D., 128.Rosenberg, T., 381.Rosenberger, U., 69.Rosenblum, B., 58.Rosenblum, L., 121.Rosenblum, M., 152, 226,Rosenblum, P., 84.Rosenfeld, M., 383.Rosenkranz, H. S., 302.Rosenstock, H. M., 42.Rosenthaler, L., 422.Rosman, H., 96.Rosowsky, A., 184.Ross, F., 176.Ross, H.€I., 442.460.233534 1ROSS, I. G., 49.Ross, J. A., 306.Ross, M., 153.Ross, R. A., 170.Ross, R. G., 485.Ross, S. D., 457.ROSS, S. T., 450.Ross, W. A., 205, 217, 219.Ross, W. C. J., 256.Rosscup, R. J., 173, 175.Rossini, F. D., 8, 9, 10,Rossman, M. G., 464, 489,Rossotti, F. J. C., 79, 88.Rossotti, H. S., 88.Rotermund, G., 213, 282.Roth, H., 451.Roth, W., 245, 343.Roth, W. L., 159.Rother, E., 131.Rothstein, A., 385.Rothwell, K., 176.Rotzler, G., 306.Rouault, A., 241.Roubein, I. F., 299.Roubinek, L., 241.Roughton, F. J. W., 91.Rouxel, J., 124.Rowe, G. G., 367.Rowe, J. M., 145, 153, 483.Rowell, D. A., 439.Rowell, J. C., 75.Rowland, A. T., 308.Rowlands, R.J., 435.Rowlinson, J. S., 9, 108.Rubalcava, H. E., 44.Rubin, R. J., 31, 52.Ruchrwen, R. A., 124.Rudd, J. F., 113.Rudney, H., 402, 408.Rudzitis, E., 133.Riichardt, C., 222.Riidorff, W., 154.Riippel, H., 96.Ruetschi, P., 100.Ruff, J. K., 124.Ruhnke, J., 211.Rumberg, B., 96.Rumley, M. K., 379.Rumsey, P., 368.Rundel, W., 243.Rundle, R. E., 162, 480,Rundqvist, S., 159, 474.Ruoff, A. L., 429.Rupchan, S. M., 292, 293.Rupp, R. L., 454.Rushizky, G. W., 301.Ruskie, H. E., 224.Russel, J. H., 327.Russell, M. E., 33.Russell, R. C., 279.Russi, S., 345.Russo, T. J., 174, 209.Ruszkiewicz, M., 264, 345.18.495, 496.483, 492.DEX OF AUTHORS’ NAMES.Rutberg, L., 358.Rutherford, T. H., 25.Rutner, E., 56.Ruzicka, L., 248.Ryabinin, A.A., 257.Ryan, J. L., 154.Rydon, H. N., 335.Rylander, P. N., 196.Ryley, J. F., 349.Rynasiewicz, J., 445.Ryschkewitsch, G. E., 119,123.Saad, F. M., 298.Sabatini, A., 140.Sacconi, L., 23, 56, 138,Sackman, J. F., 15.Saegebarth, I<. A., 179,Saffir, P., 141.Sager, F. B., 203.Sagnikres, A., 47 7.Sahoo, B., 163.Saika, A., 98, 194.Saines, G. S., 166.St. Pierre, L. E., 112.Saito, S., 485.Sakaguchi, S., 108.Sakai, K., 324.Sakamoto, M., 329.Sakata, H., 347.Sala, O., 138.Salamon, I., 312.Salas Sanceledonio, J., 440.Salem, L., 184, 332.Salemink, C. A., 222, 260.Salerni, 0. L., 269.Salesin, E. D., 442.Salfeld, J . C., 236.Salkind, A. J., 163.Salim, N., 343.Salomaa, P., 173.Salton, M.R. J., 342.Salyer, D., 441.Salzwedel, &I., 243.Samofalova, G. S., 139.Sams, D., 484.Samson, L., 47.Samson, S., 485.Samsonov, G. V., 153.Samuel, D., 181, 226.Sanborn, R. H., 25, 128.Sknchez, F., 311.Sands, D. E., 127, 472,474, 476, 484.Sands, R. H., 399.Sanecka, M., 422.Santacana, F., 413.Sant’Agostino, L., 426.Santarella, G., 148.Santavy, F., 284.Santer, J. O., 152, 233.Sapper, D. I., 110.%a, s., 447.Sarel, S., 181, 261,339, 431.140, 161.198.Sarel-Imber, M., 341.Sarett, L. H., 302, 308.Sarkisyan, R. S., 452.Sasada, Y., 488, 490, 492.Sastry, T. P., 443.Satchell, D. P. N., 180,Sato, T., 55, 332.Sato-Asano, K., 301.Satoh, D., 324.Saudri, E., 278.Sauer, J., 189, 226.Sauer, J.A., 112, 113.Saunders, M., 168, 175, 246.Saunders, T. M., 70.Saunders, W. H., 184.Saunders, W. H., jun.,Sausen, G. N., 210, 224.Savariar, C. P., 447.Savary, P., 220.Savedoff, L. G., 89, 176.Savich, I. A., 62.Saville, N. M., 335.Savina, E. V., 425.Sawicki, E., 419, 420.Sawyer, F. M., 435.Sawyer, J. O., 153.Sayer, E. E., 84.Sbrzesny, H.. 425.Scandiglia, F., 176.Scanlan, J. , 11 1.Scannell, J. P., 299.Scardaville, P. A., 421.Scatchard, G., 85.Scatturin, V., 156, 163.SCavniCar, S., 132.Schacher, G. P., 461.Schachman, H. I<., 304,Schachtschneider. J. H.,Schachtschabel, D., 302.Schafer, C., 285.Schafer, H., 22, 125, 159.Schafer, H. L., 133.Schafer, K., 9.Schaefer, H., 321.Schaefer, J . P., 201, 246.Schaeffer, R., 120.Schaeffer, T., 209.Schaffernicht, W., 85, 133,Schaffner, I<., 258, 315,Schaltyko, L.G., 105.Scharf, E., 136.Schats, J. J . C., 137.Schatz, P. N., 53, 59.Schatzmann, H. J., 392.Schauer, H., 158.Schawlos, A. L., 79.Scheer, I., 323.Schenck, G. O., 224, 308.Schenk, G. H., 448.Scheraga, H. A., 182, 501.186.177.353, 356.53.139.318INDEX OF AUTHORS, NAMES. 535Sclierba, L. D., 82.Scherer, F., 150, 233.Scherer, J . R., 48, 49, 51,Scherrer, R. A., 249.Schick, H. L., 26.Schier, O., 342, 343.Schikora, E., 222.Schildkraut, C., 302, 356.Schilling, W., 18.Schilt, A. A., 159.Schindler, O., 324, 326,327, 328, 329.Schipper, E., 267.Schirber, J. E., 472.Schlafer, H. L., 85, 139.Schlag, E.W., 31, 37.Schlag, J., 96.Schlesinger, H. I., 122.Schleyer, P. von R., 168,Schlittler, E., 285, 286.Schlosser, M., 207.Schlossberger, J . E., 367.Schluter, E. C., jun., 453.Schmadel, H., 339.Schmandke, H., 337.Schmauch, L. J., 436.Schmeising, H. N., 183,Schmeisser, M., 126, 136.Schmerzler, E., 432.Schmid, E., 129.Schmid, E. D., 52.Schmid, H., 235, 280, 288,Schmid, L., 431.Schmid, W., 326.Schmidbauer, H., 127.Schmidt, H., 136, 242,Schmidt, J . E., 223.Schmidt, M., 127, 134, 135,Schmidt, 0. T., 339.Schmidt, W., 454.Schmidtke, H. H., 141.Schmidt-Nielsen, K., 393.Schmitz-DuMont, O., 154.Schmutz, J., 287.Schneider, F., 337, 419.Schneider, F. W., 31.Schneider, J., 125.Schneider, R., 152, 233.Schneider, W., 412.Schneider, W.G., 57, 209,Schnitzer, M., 460.Schollkopf, U., 244.Schoen, J., 94.Schoenfelder, C., 128.Schofield. I<., 295.Scholtz, M., 262.Schomaker, V., 149.Schonbaum, G. R., 180.Schonland, D. S., 69.52.245.184.289.347.136.268.Schotz, S., 248.Schrauzer, G. N., 145, 222,Schreiber, H., 102.Schreiner, S., 233.Schreurs, J. W. H., 73.Schroder, E., 452.Schroeder, H., 272, 426.Schroeder, W. A., 499.Schroter, H., 126, 328.Schropp, W., jun., 144.Schubert, A., 325.Schubert, W. J., 237.Schubert, W. M., 172.Schueller, K. E., 188.Schuldiner, S., 432.Schulek, E., 414, 417, 440,Schuler, R. H., 77.Schuller, F., 52.Schuller, P. L., 222.Schuller, W. H., 254.Schulz, G. V., 105.Schulz, H., 205.Schulz, W., 343.Schulze, H., 261.Schumacher, H.J., 36, 37,Schumann, H.-D., 135.Schumm, R. H., 22.Schupbach, V. E.. 416.Schiitte, H. R., 282.Schut, R. N., 314.Schwartz, D. P., 429.Schwartz, G. M., 223, 239.Schwartz, I. L., 386.Schwartz, J . H., 427.Schwarz, J. S. P., 250.Schwarz, R. F., 58.Schwarz, V., 313.Schwarzenbach, G., 88,Schweet, R. S., 298, 302.Schweitzer, E. E., 175.Schweitzer. G. K., 425.Schweizer, E. E., 243.Schweizer, E. H., 266.Schweizer, E. W., 274.Schwerz, H. E., 418.Schwimmer, S., 329.Scintee, V., 450.Scott, A. I., 235, 277.Scott, c. G., 439.Scott, D. W., 12, 14.Scott, F. L., 192.Scott, G., 76.Scott, J. F., 298, 361.Scott, J. M., 176.Scott, J. M. W., 183.Scott, R. G., 109.Scott, R.L., 451.Scouloudi, H., 497.Scribner, W. G., 445.Seager, S. L., 436.Searcy, A. W., 25, 473.Searle, H. T., 15, 130.234.444, 449.126.116, 156.Searles, S., 121, 262.Seaton, J. C., 256.Secci, M., 123.Secco, E. A., 163.Sechkarev, A. V., 51.Sederholm, C. H., 12, 45,Sedlak, H., 268.Seeds, W. E., 301.Seefield, E. W., 452.Seel, F., 130, 134.Seelye, R. N., 255.Segal, B., 68.Segal, L., 343.Segerman, E., 488.Segnini, D., 194.Sehon, A. IT, 27.Seibold, E. A., 51.Seidel, W., 130.Seifert, H.- J., 155.Seifert, R., 367.Seifert, W. K., 168, 245.Seils, C. A., jun., 426.Seinmetz, R., 224.Sekerskii, S., 428.Seki, T., 435.Sekiya, M., 225.Sekuzu, I., 398, 399.Seibin. J., 160.SelCn, H., 55.Selig, H., 158.Selivokhina, 1cI.S., 124.Selleby, L., 332.Semashko, I. A., 153.Seminova, V. A., 438.Sen, B., 416, 418, 436.Sengupta, P., 253, 278.Senior, J. B., 180.Senise, P., 425.Senko, M. E., 489.Seoane, E., 283.Sephton, H. H., 332.Series, G. W., 78.Serota, S., 324.Serrano-Berges, L., 448,Serrins, R. B., 25.Setkina, V. N., 171.Settle, J. L., 17.Seyferth, D., 123, 128, 144,Shabarov, Yu. S., 241.Shabica, A. C., 305.Shabtai, J., 243.Shaffer, R. R., 252.Shaffer, W. H., 52.Shah, R. C., 278.Shah, V. R., 278.Shakir, K., 447.Shaligram, A. M., 250.Shaltiel, N., 453.Shamgar, A. H., 341.Shamma, M., 258.Shanes, A. M., 370, 372,380, 382, 386.Shapiro, H. S., 300.247.449.207536 INDEX OF AUTHORS' NAMES.Shapiro, I., 120.Shapiro, R., 295.Sharefkin, J.G., 418, 419.Sharma, N. N., 445.Sharon, N., 342.Sharp, D. W. A., 118, 121,122, 143, 147, 159.Sharpe, A. G., 137, 160.Shashoua, V. E., 64.Shatenshtein, A. I., 186,Shaw, B. L., 56, 143, 147.Shaw, P. E., 254.Shaw, R. A., 131.Shaw, T. I., 371, 382, 390.Shaw, W. H. C., 412.Shchukarev, S. A., 22.Shearer, H. M. M., 149,464, 487, 491.Shears, E. C., 451.Shechter, H., 208, 221.Sheellan, J. T., 268.Sheft, I., 153.Sheka, I. A., 156.Sheldon, J. C., 118.Sheldon, M. V., 447.Shemyakin, n1. M., 209,329.Sheppard, N., 52, 145, 151,217, 256, 285, 493.Sheppard, R. C., 268.Sheppard, W. A., 134, 223,Sheridan, J., 46, 47, 48, 54,Sherif, F. G., 130.Sherle, A. I., 139.Sherman, E., 264.Sherwood, R.M., 459.Sheveleva, N. S., 453.Shevkoplyas, A. ti., 451.Sheyanova, F. R., 457.Shibaev, V. N., 241.Shibata, S., 424, 426.Shields, H., 72.Shiloff, J. C., 156.Shilov, E. A., 188.Shimada, A., 487, 488.Shimaoka, A., 323, 324.Shimarouchi, T., 49, 51.Shimizu, F., 298.Shimizu, Y., 324.Shimozawa, T., 55.Shiner, V. J., jun., 177,Shintani, R., 488.Shiono, R., 492.Shipulo, G. P., 48, 54.Shirane, G., 467, 468.Shkolnikova, L. M., 483.Shmukler, H. W., 408.Shomate, C. H., 13, 16.Shoolery, J. N., 259, 287,Shoosmith, J., 38, 45.Shoppee, C. W., 306, 327.187.224.126.182.305.Shore, S. G., 56.Shore, V. C., 495.Shrivastava, H. N., 285,Shropshire, J., 473.Shtexer, S. M., 10.Shubnikov, A. V., 467.Shuey, E.W., 297.Shugam, E. A., 483.Shugar, D., 304.Shuler, K. E., 31.Shull, H., 54.Shumaker, V. N., 302.Shunk, C. H., 403.Shuvalov, L. A., 466.Shvedov, V. P., 433.Shvo, Y., 258.Sicher, J., 171, 176, 337.Sicre, J. E., 36.Sicular, A., 385.Siddiqui, S., 286.Sie, H.-G., 332.Sieber, G., 265.Siebert, R., 335.Siebert, W., 139.Siegel, B., 124.Siegel, S., 74.Siekevitz, P.. 396.Sigg, H. P., 306.Sih, C. J., 325.SillCn, L. G., 87, 154, 163.Silver, M. S., 239.Silverman, M., 342.Silverman, S., 59.Silverton, J. V., 285, 493.Sim, G. A., 251, 258, 464,494, 495, 498.Simanov, Y. P., 118.Sime, J. G., 460.Sime, R. J., 26, 156.Simmonds, D. H., 435.Simmons, D. L., 290, 291.Simmons, H. E., 207, 227.Simmons, H. E., jun., 176.Simmons, P., 194.Simms, E.S., 353, 355.Simon, A., 131, 135.Simon, G., 134.Simon, H., 282, 343.Simon, S. E., 383.Simon, W., 435.Simonitsch. E., 235, 280.Simonov, V. I., 463, 486.Simons, J. P., 41.Simonsen, J., 255, 256.Simonsen, S. H., 443.Simonson, T. R., 82.Simonyi, I., 448.Simpson, L. B., 102.Simpson, W. T., 52.Sims, D., 112.Sims, J. W.. 247.Singer, J., 478.Singer, M. F., 359, 360.Singer, T. P., 398, 400.493.Shuskus, A.-J., 71.Singh, E. J., 430.Singh, H., 113.Singh, L., 63.Sinke, G. C., 9, 11, 12.Sinsheimer, R. L., 303, 356,sipo5, F , 176.Sirokman, F., 221.Sirs, J. A., 92.Sisido, K., 252.Sisler, H. H., 123.Sisman, E., 448.Sisti, A. J., 204.Sistrom, W. R., 394.Sixma, F. L. J., 185.Skaltenbronn, J., 280.Skancke, P.N., 51.Skattebd, L., 211.Skazka, V. S., 105.Skell, P. S., 168, 175, 210,Skelton, L. B., 414.Skinner, A. C., 118.Skinner, H. A., 9, 10, 11,Skinner, J. M., 424.Skinner, W. A., 279.Skipski, V. P., 431.Sklar, R., 286.Skolbovski, K. A., 229.Skolik, J., 429.Skolnik, S., 74.Skorinko, G., 46, 47.Skou, J- C., 375, 391, 392.Sltrobek, A., 314.Skuratov, S. M., 9, 10, 13,SlAdeEek, J. , 437.Slater, C. A., 259.Slater, E. C., 397, 402, 407,Slater, N. R. , 28, 30, 37, 51.Slates, H. L., 277, 310.Sleva, S. F., 458.Slichter, C. P., 98.Slichter, W. P., 109, 112.Slites, H. L., 235.Sloan, G. J., 75.Sloane, E. M., 159.Sloane-Stanley, G. H., 378.Slomp, G., 209, 305.Slota, P. J., 123.Slowinski, E.J., 49.Slusanschi, H., 441.Slyusareva, R. L., 454.Smales, A. A,, 413.Small, A. M., 312.Small, J. D., 296.Smaller, B., 70, 74, 77.Smallman, B. N., 372.Smellie, R. M. S., 354, 355,357, 359, 361, 364.Smidt, J., 145, 147.Smiley, R. A., 208, 221.Smirnov, M. V., 118.Smirnov, V. R., 485.357.239.15, 24.20, 21, 22.408INDEX OF AUTHORS’ NAMES. 537Smirnova, T. S., 466.Smissman, E. E., 237,Smit, W. M., 461.Smith, A. I?., 283.Smith, B. C., 118.Smith, B. V., 194, 195.Smith, C. R., jun., 217.Smith, D. C. C., 275.Smith, D. F., 44.Smith, D. M., 442.Smith, D. R., 130.Smith, E. A., 439.Smith, E. D., 429.Smith, E. E. B., 297, 351.Smith, E. M., 443.Smith, F., 198, 338, 346,Smith, F. A. S., 167.Smith, F. T., 41.Smith, G.F., 275, 288, 415.Smith, G. F. W., 176.Smith, G. W., 157, 245.Smith, H., 238, 274, 276,Smith, H. G., 271.Smith, H. J., 428.Smith, J. C., 12.Smith, J. C. B., 412.Smith, J. D., 296, 299, 300.Smith, J. F., 46.5.Smith, J. J., 150.Smith, J. V., 485.Smith, J. W., 55.Smith, K. C., 298.Smith, L., 398.Smith, L. C., 169, 213.Smith, L. L., 88, 315.Smith, &I. J. A., 70.Smith, M. L., 177.Smith, M. S., 358.Smith, P. J. A., 178.Smith, P. W., 157.Smith, R. D., 133, 207.Smith, S., 89, 173, 176.Smith, S. G., 208.Smith, T. D., 243.Smith, T. E., 33.Smith, T. G., 369.Smith, W., 217.Smith, W. C., 133, 134, 206,Smith, W. IS., 415.Smith, W. R., 438.Smith, W. T., 71, 88.Smoler, I., 101.Smolik, S., 286.Smolinsky, G., 167, 219,Smullin, C.F., 439, 450.Smutny, E. J., 241.Smyth, C. P., 61.Sneen, R. A., 173.Snell, J. F., 238.Snelson, A., 10.Snover, J. A., 119, 196.Snyder, H. It., 275.347, 349.282, 320.207, 230.229.Snyder, L. C., 75.Snyder, R. G., 118.Sobue, H., 349.Socolovschi, R., 424.Soll, AT., 125.Soep, H., 453.Sokol, P. E., 176.Sokolova, E. V., 441.Solo, A. J., 291, 311.Solodornikov, S. P., 77.Solomon, A. K., 380, 385,Solomon, D. H., 204.Solomon, E., 456.Solomon, I. J., 120.Solomons, C., 85.Soloway, S. B., 168, 245,Solymosi, F., 445.Somasundaram, V., 50.Somasundram, K. M., 65.Somerfield, G. A.. 279.Sommer, A., 47, 123.Sommerville, R., 358.Sondheimer, F., 184, 198,231, 258, 274, 307, 312,313, 328.393.247.Sonin, A.S., 466.Sonnenberg, J., 198, 223,Sorgeson, A. M., 142.Sorm, F., 249, 251, 252,259, 272, 306, 314, 315,316.SormovL, Z., 272.Sorof, S., 433.Soruni, H., 489.Sosnovsky, G., 202.Soucek, &I., 252.Sousa, J. A., 200.Sowden, J. C., 333, 334,Sowden, R. G., 36.Sozzj, J . A., 419.Spackman, D. H., 500.Spacu, P., 441.Spahr, P. F., 299.Spain, J. D., 428.Spainham, J. D., 176.Spalding, E. T., 172.Spalthoff, w., 81.Sparks, R. A., 466, 494.Speakman, J. C., 465, 495.Spedding, IT., 331.Spence, 31. N., 433.Spencer, C. F., 437.Spencer, C. W., 25.Spencer, J. F. T., 331.Spencer, J. L., 267.Spencer, R. R., 340, 342.Spenser, I. D.. 275.Sperlich. H., 422.Sperling, L. H., 105.Speziale, A.J., 207.SpiCkovL, J., 429.Spingler, H., 290.244.342, 344.Spinner, E., 194, 269.Spirin, A. S., 300, 303.Spiro, M., 85.Spiro, M. J., 401.Spoel, H., 66.Spokes, G. N., 192, 227.Spooner, F. J., 484.Spoors, J. W., 339, 340.Sporn, M. B., 368.Spring, F. S., 256, 266,Sprinivasan, P. R., 237.Sprinson, D. B., 237.Squirrell, D. C. M., 410,Srinivasan, R., 34, 244.Srivastava, H. N., 61.Srivastava, T. S., 447.Stacey, M., 269, 272, 335,341, 343, 345.Stache. U., 321.Stadler, P. A., 216.Stafford, S. L., 128.Stahl, H. O., 150, 233.Stam, B., 466.Stambaugh, R. L., 429.Stamm, 0. A., 235.Stamm, R. E., 85.Stammreich, H., 138.Stander, C. &I., 425.Stankoviansky, S., 447.Stanley, E., 108.Stanley, T. W., 419, 420.Stansfield, M., 310.Stanton, G.M., 189.Staples, D. A, 378.Staples, P. J., 63.Starer, I., 168, 239.Starke, K., 156.Starkweather, H. W., 110.Starr, J. L., 298.Start, P. A., 264.Statton, W. O., 109.Staudinger, €I., 248.Stauffer, C. H., 170.Stauffacher, D., 249.Staveley, L. A. K., 23, 34.Stawpert, W., 427.Steacie, E. W. R., 37.Steel, C., 30, 35.Steele, D., 52.Steele, R. M., 157.Steele, T. W., 423.Stegerhoek, L. J., 220.Strehlow, H., 80.Stehr, C. E., 268.Stehr, E., 451.Stein, G., 84.Stein, W. D., 380.Stein, W. H., 500.Steinbach, H. B., 382.Steinberg, M., 312.Steinhardt, J.. 19.Steinrauf, L. K., 494.Stejskal, E. O., 98.Stellwagen, N. C., 141.323.452538 INDEX OF AUTHORS' NAMES.Stensby, P., 88.Stepanenko, E.&I., 456.Stepanov, A. V., 433.Stephen, A. M., 198, 346.Stephen, M. J., 62, 64, 65,Stephen, W. I., 416, 446.Stephenson, J. S., 211.Stephenson, L. 307.Stephenson, M. L., 298,Sterling, C., 348.Stermitz, F. R., 178, 282.Stern, J. R., 387.Stern, K. H., 84.Stern, R., 280.Stern, S. A., 129.Sternberg, H. W., 144.Sternberg, J. C.. 437.Sternhell, S., 258.Sternlicht, H., 73.Sterns, M., 128.Stetter, H., 272, 277.Stevens, A., 304.Stevens, I. D. R., 89, 176.Stevens, R., 216.Stevens, T. S., 172, 175.Stevenson, D. P., 46, 63.Stevenson, F. J., 414.Stevenson, R., 256, 257.Steward, R., 180.Stewart, A. T., 470.Stewart, G. H., 429, 436.Stewart, H. J., 482.Stewart, J. E., 459.Stewart, J. H., jun., 456.Stewart, R., 166.Steyermark, A., 452.Stich, K., 306.Stickings, C.E., 264.Stiddard, M. H. B., 143.Stiles, M., 192, 204, 227.Stiles, R. M., 192, 227.Stimson, V. R., 170.Stitch, M. L., 55.Stoch, J., 446.Stock, D. I., 84.Stock, J. T., 442.Stock, L. M., 185, 187.Stockmayer, W. H., 102,Stoffel, W., 217.Stoffyn, P. J., 339, 351.Stoicheff, B. P., 46, 54.Stolar, S. M., 315.Stoll, A., 325.Stone, F. G. A., 118, 121,128, 145, 146, 147, 150,234.73.361.104.Stone, K. G., 426.Stone, R. L., 461.Stonhill, L. G., 461.Stoodley, R. J.. 350.Stoops, R., 359.Stork, G., 200, 242, 256,311.Story, P. R., 168, 203,Stothers, J. B., 242.Stott, G., 63.Stotz, E., 398.Stoughton, R. W., 88.Strachan, R. G., 309.Strachan, W. S., 256.Strachota, J., 429,Strack, E., 222.Strahm, R.D., 121.Strain, H. H., 427, 433.StraIey, J. W., 52.Strandberg, B. E., 495.Strange, R. E., 342.Stranks, D. R., 26, 140.Stratton, R. F., 48.Straub, D. K., 139.Straub, F. B.; 389.Strauss, F. B., 327.Strauss, H., 184.Strauss, H. L., 76, 230.Street, C. N., 153.Strehlow, H., 85, 94, 101.Streitweiser, A., 185.Strell, M., 280.Strelow, F. W. E., 434.Strem, M., 437.Streuli, C. A., 448, 450.Strickland, E. H., 220.Stricos, D. P., 445.Striegler, K., 229.Strobach, D. R., 333, 334,Stroganov, E. V., 478.Strohmeier, W., 56, 143,Stromberg, R., 156.Strarmme, K. O., 136, 247,Strong, F. M., 275.Strong, R. L., 96, 123,Struble, M., 248.Struck, W. A., 254.Strunz, H., 477.Stuart, W., 474.Stuart, W.I., 154.Stubbles, J. R., 25, 157.Stubbs, F. J., 34.Stuck, W., 451.'Stucki, L. R., 436.Stuckwisch, C. G., 267.Stull, D. R., 9. 12.Sturtevant, J. M., 19.Su, J. C., 297.Subba Rao. B. C., 118,119,197, 199, 213.Subbarao, E. C., 468.Sublett, R. L., 420.Suchf, L. M., 259.Suda, M., 255.Suemune, Y., 476.Sueoka, N., 302.Sugasawa, S., 270.Sugawara, T., 478.230, 245, 246.344.151.483.187.Sugden, T. M., 126.Sugita, T., 240.Sugiyama, H., 230.Suh, J. T., 237.Suhr, H., 190, 226.Sujishi, S., 126.Sukh Dev, 258.Sukhotin, A. M., 82.Sula, J., 431.Suld, G., 285.Sullivan, J. C., 141.Sully, B. D., 449.Sulzberg, T., 419.Summers, G. H. R., 306,307, 308, 314.Sundaralingam, M., 491.Sundberg, 0.E., 438.Sundheim, B. R., 76.Sunner, S., 20, 26.Surma, M., 61.Surovjr, J., 437.Susano, C. D., 411.Suschitzky, H., 226, 458.Susz, B. P., 56.Sutcliffe, J. F., 380.Suter, P. J., 256.Sutherland, E. W., 297.Sutherland, I. O., 229, 238.Sutor, D. J., 289, 492,Suttle, J. F., 154.Sutton, G. J., 62.Sutton, J. R. B., 415.Sutton, L. E., 56, 61,Swain, C. G., 82, 172,Swalen, J. D., 48, 54, 55.Swan, B., 330.Swan, P. R., 108, 109.Swan, R. C., 384.Sweeley, C. C., 305.Sweeney, C., 117.Sweet, T. R., 441.Swenson, C. A., 53, 472.Swift, E. H., 442.Swinbourne, E. S., 32.Swindells, R., 309.Swinehart, J. S., 223.Swink, L. N., 140, 481.Svennerholm, L., 377, 378,Sverdlov, L. M., 51, 52.Svoboda, M., 171, 337.Svoboda, V., 447, 457.Sych, G., 337.Sykes, K.W., 82.Sykes, P. J., 219.Sfkora, V., 251.Symons, M. C. R., 63, 69,70, 71, 72, 73, 74, 75, 76,77, 81, 83, 117, 135, 137,159, 166, 168.Symons, N. K., 109.SyneCek, V., 162.Synek, L., 451.494.195.181.379INDEX OF AUTHORS’ NAMES. 539Syrkin, Ya. K., 56, 147,Szab6, L., 341.Szab6, P., 341.Szarvas, P., 429.SzmrecsAnyi, I. V., 449.Szumer, A. Z., 218.Szwaj, M., 433.Szwarc, M., 193.Szybalski, W., 300.Tablino, V., 107.Tabuchi, D., 95.Tachiore, H., 16.Tadokoro, H., 108.Taft, R. W., jun., 168,Tagver, B. A., 467.Tahara, A., 253.Tai, H., 459.Taimni, I. K., 460.Takagi, T., 348.Takagi, Y., 361.Takahashi, T., 435.Takaki, T., 376.Takaki, Y., 488, 490.Takeda, K., 251, 319, 323,Takeda, M., 98, 102.Takemori, S., 399.Takenchi, T., 250.Takeshita, M., 343.Takeuchi.Y., 486.Takiyama, K., 442.Talaat, M. Y. A., 130.Talamini, G., 112.Talsky, G., 134.Tamm, C., 200, 306, 324,Tamm, K., 80, 94.Tamres, M., 262.Tamura. T., 325.Tanabe, K., 173, 324.Tanaka, K., 110.Tanaka, T., 16, 296.Tanaka, Y., 47, 339.Tananaev, N. A., 417, 424.Tandon, S. G., 441,Tandon, S. N., 460.Tanner, F. W., 229.Tanner, K. N., 45.Tarbell, D. S., 261.Tata, J. R., 429.Tate, D. P., 201.Tatevsky, V. M., 44.Tatlow. J. C., 269, 335.Taub, B., 207.Taub, D., 235, 277, 310,Taube, H., 81, 92, 138, 141.Taurins, A., 268.Taylor, C. A., 464, 490.Taylor, D. R., 291.Taylor, E. C., 221, 277.Taylor, E. H., 282.Taylor, F.B., 122.170.169, 173.324.325, 326.314.Taylor, G. A., 276.Taylor, H. F. W., 486.Taylor, I. M., 386.Taylor, M. R., 478.Taylor, N. E., 162, 494.Taylor, N. F., 340.Taylor, R., 49, 127, 185,Taylor, R. L., 35.Taylor, S. M., 88.Taylor, S. R., 434.Taylor, W. C., 284.Taylor, W. I., 285, 286,Teach, E. G., 127, 212.Teare, P. W., 488.Tebben, A., 159.Tedder, J. M., 225, 263.Teeter, H. M., 202, 219.Teichert, K., 432.Teichmann, G., 127.Teichner, S. J., 160.Templeton, D. H., 133,Templeton, J. F., 258.Templeton, W., 203, 242.Ten, Ten, 433.Tener, G. M., 296.Tengler, H., 144.Teorell. T., 389.Teranishi, R., 437, 438.Terao, N., 485.Terasawa, T., 319.Ternbah, M., 291.Terner, C., 369, 370, 386.Ter Borg, A.P., 230.TesaIik, K., 436.Tesi, G., 130, 131.Tessier, J., 318.Tessmar, K., 102.Testa, E., 262.Tezuka, T., 225.Thaller, V., 221.Tharp, A. G., 25.Theilacker, W., 273.Thelin, J. H., 225.Theobald, R. S., 330, 435.Theubert, F., 144.Theuerer, H. C., 423.Thews, G., 92.Thibon, H., 18.Thieberg, K. J. L., 252.Thiel, M., 268.Thiele, E., 30.Thilo, E., 131.Thoma, J. A., 346, 348.Thomas, A. C., 415.Thomas, B. R., 172.Thomas, D. B., 444, 455.Thomas, D. K., 484.Thomas, G., 283.Thomas, J., 394.Thomas, J. H., 83.Thomas, J. R., 76.Thomas, P. J., 32.Thompson, A. R., 490.186.288.469. 473, 489.Thompson, C. W., 471.Thompson, D., 246.Thompson, D. A., 442.Thompson, J. H., 425.Thompson, M. J., 323.Thompson, M.R., 443.Thompson, N. R., 121.Thompson, N. S., 349.Thompson, Q. E., 202.Thomson, C. G., 376.Thomson, P. L., 238.Thomson, R. Y., 357, 359.Thonelius, H., 234.Thorell, B., 91.Thornburg, W., 433.Thornton, E. R., 82, 181.Thudium, F., 307.Thun, R. E., 456.Tichy, M., 176.Tickner, A. W., 26.Tidwell, E. D., 43, 46.Tiedemann, G., 132.Tiers, G. V. D., 228.Tiess, D., 123.Tiffin, A. I., 348.Tigchelaar-Lu t j eboer,H. D. A., 210.Tillu, M. M., 427.Tillett, J. G., 181.Timell, T. E., 339, 346,Timofieev, B. I., 20, 21.Tinkham, M., 69.Tinoco, I., 57, 64, 65,Tipson, R. S., 331.Tishchenko, G. N., 480.Tissieres, A., 302.Tjebbes, J., 10.Tlumac. F. N., 207.Tobe, M. L., 63, 141, 142.Tobias, I., 45.Tobias, R. S., 87, 133.Tobin, M.C., 108.Tobinaga, S., 258.Tobolsky, A. V., 102, 111,Todd, (Sir) A. R., 295, 296,Todd, S. S., 12.Todd, W. M., 332.Toeniskoetter. R. H., 125.Togoeva, S. K., 9.TokAr, G., 448.Tokura, N., 347.Tolksdorf, S., 312.Tolstaya, T. P., 186.Tolstopyatova, A. A., 202,Tomimatsu, T., 285.Tomlinson, S., 369.Tomlinson, T. E., 61.Tompa, H., 102.Toms, B. A., 417.Tong, J. Y.-P., 141.Toor, E. W., 63.Topchiev, A. V., 55.349, 350.302.112, 113.298, 409540 INDEX OF AUTHORS’ NAMES.Topol, L. E., 133.Topsom, R. D., 262.Torochesnikov, N. S., 438.Toromanoff, E., 312, 318.Tortorella, V., 325.Toste, A. H., 283.Tosteson, D. C., 386, 389,Touchstone, J. C., 432.Tourky, A. R., 56.Touster, O., 332.Tower, D. B., 367.Towers, G.H. N., 431.Towndrow, E. G., 428.Townes, C. H., 55, 58.Townley, B., 316.Townsend, M. G., 71, 73,Townsend, R. J., 264.Trachtenberg, E. N., 314.Trahanovsky, W. S., 138.Train, K. E., 305.Trammell, G. T., 71, 72.Treibs, A., 263.Treibs, W., 202, 206, 231,Treinen, A., 84.Treloar, L. R. G., 102, 103,Trkmillon, B., 423.Trenner, N. R., 309.Treshchova, E. G., 241.Tresize, M. A., 367.Trevalion, P., 71.Trifan, D. S., 140.Tritch, H. R., 438.Trippett, S., 204, 308.TrojBnek, J., 313.Tromans, F. R., 130.Tron, F., 458.Troskin, A. S.. 383.Trotman, J., 33.Trotman-Dickenson, A. I?.,35, 36, 38, 39, 41.Trotter, J. , 489, 490.Truce, W. E., 201.Trueblood, K. N., 296, 477,488, 494, 495.Truscoe, R., 385, 392.Truter, M.R., 129, 487.Tscherter, H., 285.Tschesche, R., 218, 258,Tschesche, T., 326.Tschuikow-Roux, E., 31.TSOU, C. L., 400.Tsubomura, H., 187.Tsubota, H., 434.Tsuchida, R., 145, 161.Tsuda, K., 324, 325.Tsukamoto, A., 198, 222.Tsuruta, T., 108.Tsutsui, E. A., 253.Tsutsui, hT., 148, 253.Tsuzuki, T., 12.Tsvetkov, V. N., 102, 107.393.74, 75.274.109, 111.327.Tuck, B., 457.Tuck, D. G., 115.Tucker, R. G., 395.Tuckerman, M. M., 433.Tuddenham, W. M., 459.Tufts, B. J., 418.Tuijnman, C. A. F., 106.Tulinsky, A., 465.Tullock, C. W., 133, 206,Tulmac, F. N., 128.Tung, L. H., 113.Tunitskii, L. N., 44.Tunlrelo, E., 470.Tunmann, P., 287.Tuppy, H., 283.Turco, A., 158, 163.Turner, A. C., 48, 126.Turner, D.W., 306.Turner, H. S., 122.Turner, J, C., 284, 340.Turner, R. B., 8, 264,Turner, W. B., 221, 256,Turvey, J. R., 345.Tute, M. S., 272.Tuthill, S. M., 450.Tuttle, 1‘. R., 75.Tuttle, W. S., 387.Tvorogor, N. N., 153.Tweedie, V. L., 200.Tyler, J. K., 46, 47, 54.Tyminski, A., 349.Tyou, P., 438.Tyree, S. Y., jun., 157.Tzschach, M., 127.Ucciani, E., 218.Uchino, N., 339.Uda, H., 280.Udenfriend, S., 260.Ueberwasser, H., 310.Ueda, Y., 330.Ueyama, T., 107.Ugi, I., 191, 274.Ukei, S., 478.Ullman, R., 10s.Ullyot, G. E., 285.Ulm, I<., 146, 149.Ulrich, W. F., 469.Umanskii, N. M., 468.Undheim, K., 63.Unni, M. I<., 199.Untch, K. G., 252.Unterleitner, F., 468.Urbach, H. B., 37.UrbBnski, T. S., 426.Urquiza, R., 308.Urry, G., 122, 127.Uryson, S.O., 300.UskokoviC, M., 314.Ussing, H. H., 381, 386.Utiyama, H., 104.Uyeo, S., 290.Uzman, I,. T,., 379.207.291.271.Vagurtova, 11. N., 118.Vahrman, M., G6.Vainstein, B. K., 463, 465,Vainstein, F. M., 188.Valenta, Z., 279, 291.Valenti, V., 144, 158.Vallarino, L., 148.Valls, J., 313.van &Auken, T. V., 238, 266.Van Bibber, &‘I. J., 368.van Dam, M. J. D., 432.van Deenen, L. L. M., 220.van deli Handel, J., 65.VandenHeuvel, W. J . A. ,van der Kerk, G. J. M.,Vanderslice, J. T., 45.van der Waals, J. H., 78.van Duuren, B. L., 455.Vangedal, S., 308.van Helden, R., 230.van Heyningen, SV. E.,Van Holde, I<. E., 107.VaniCkova, E., 448.van Kamp, H., 9.van Krevelin, D.W., 66.van Looy, H.. 169.van Rleerssche, &I., 488.Van Mekerk, J. N., 433.van Moorselaar, R., 321.Vannerberg, N. G., 477.van Raaphorst, J. G., 137.van Riesenbeck, G., 101.Van Rict, R., 48.van Schouwenburg, J. C.,Van Slyke, D. D., 415.van Tamelen, E. E., 270,275, 282, 283, 288.van Tassel, J. H., 461.van Wijk, H. F., 461.Van Willis, W., 435.Van Wittenau, M. S., 229.Varfolomeeva, L. A., 468.Varnerin, R. E., 34.VaSrikovA, E., 418.Vasel’ev, N. I., 241.Vasiliev, R., 448, 450.Vasil’kova, I. V., 22.Vaska, L., 159.Vasyunina, N. A., 334.Vaughan, J., 262.Vaughan, P., 463.Vaughan, P. A., 80, 473.Vaughan, W. E., 9.Vaughan, W. R., 267.Vaughn, J. D., 21.Vaupr6, R., 323.VAvrovB, M., 429.Veal, P. I,., 235.VBcGra, bI., 431, 461.Veda, T., 264.Vedam, I<., 468.477.305.149.376, 377.447INDEX OF AUTHORS’ NAMES.541Veenendaal, A. L., 466.Veeravagu, P., 216.Vehlinger, H. P., 326.Velasquez, A. A., 283.Veldstra, L., 402.Velluz, L., 311, 317, 318,Venanzi, L. M., 56, 140.Venkataraman, B. , 92.Venkataraman, K., 199.Venkateswarlu, K., 50.Venner, H., 294.Verheijden, J. P., 339.Verkade, P. E., 220.Verkhoud, N. N., 166.TTerlicchi, L., 279.Verloop, A., 321.Verma, R. D., 50.Verma, S., 187.Vernengo, M. J., 285.Vernon, C. A., 136, 174,177, 181, 188, 190.Vernon, J. M., 276.Verzele, M., 259.Vestergaard, P., 427, 428.Vetchinkin, S. I., 77.Vetterlein, R., 245.Vielstich, W., 99, 100.Vieregge, H., 210.Vignau, M., 318.Vigoureux, S., 149.Vilkas, M., 243.Villadsen, J..475.Villain, J., 467.Villotti, R., 306.Vincent, D. L., 347.Vintaiken, E. Z., 26.Vischer, E., 222.Visco, R. E., 82.Vishweshwaraiah, K. nT. ,Visser, B. J., 9.Viswanathan, N., 293.Vitek, R. K., 440.Vodar, B., 52.Volker, O., 213.Vogel, A. I., 55, 66.Vogel, A. N., 438.Vogel, E., 238.Voigt, D., 65.Voinovitch, I. A., 453,Voitovich, B. A., 156.Vojtgch, F., 450.Volchek, B. Z., 102.Vol’f, L. A., 446.Volini, F., 432.Volke, J., 100.Vol’kenshtein, M. V., 64,Volkin, E., 357.VolkovA, V., 100.Vollmar, A., 205.Volpin, M. E., 201, 230.von Ardenne, R., 343.Von&Sek, I?., 252.323.439.455.104.REP.-VOL. LVIIvon Bebenburg, W., 337.von Bertalanffy, A., 381.von Bruchhausen, F., 285.von Egidy, A.I., 21.von Eller-Pandraud, H.,von Euw, J.. 326, 327.von Hobe, D., 56.Vonnegat, B., 88.von Philipsborn, W., 280.von Stackelberg, M., 101.von Sydow, E., 486.von Wartburg, A., 328.Voorn, M. J., 108.Vorobiev, A. F., 21.Voronova, A. A., 477.Vossos, P. H., 162.VotakovA, B., 431.Vozzella, P. A., 456.Vredenburgh, W. A., 319.Vu, H., 52.Vyas, A., 61.Vjrsotskii, R. Ya., 433.Wachi, F. M., 437.Wada, A,, 56, 57.Wada, E., 107.Wada, Y., 48, 129.Waddington, G., 12, 14,122, 136, 137.Wade, K., 119, 121.Wadier, C., 460.Wadkins, C. L., 406, 408.Wadsley, A. D., 154.Wadso, I., 20, 22, 26.Waelsch, H., 368.Wanninen, E., 446.Waggoner, J. H., 52.Wagner, A., 345.Wagner, F., 280, 281.Wahl, A.C., 89, 140.Wahrhaftig, A. L., 42.Wailes, P. C., 217.Wainio, W. W., 398, 399.Wait, S. C., 47, 49.Wakefeld, B. J., 218.Wakefield, D. B., 160.Walborsky, H. &I., 240.Waldow, C. H., 126.W7alker, A., 162.Walker, D. F., 259.Walker, D. &I., 204.Walker, G. J., 348, 349.Walker, J., 268.Walker, L. R., 69.Walker, P. G., 343.Walker, R., 314.Walker, R. W., 314.Wall, F. T., 104.Wall, M. E., 312, 324.Wall, R. A., 330.Wallenstein, M. B., 42.Waller, J. G., 116.Wallin, T., 87.Wallis, E. S., 307.Wallis, J. W., 121.492.Wallis, R. F., 59.Wallwork, S. C., 479, 492.Walrafen, G. E., 81, 135.Walsh, A., 458, 459.Walsh, J. T., 438.Walsh, P. M., 123.Walsh, P. N., 25, 47.Walshaw, S. M., 55.Walter, B.H., 265.Walter, N. M., 109.Walton, A. K., 65.Wampler, D. L., 475.Wang, J. H., 139, 399.Wang, K.-T., 431.Wannagat, U., 127.Wanzlick, H. W., 222.Warawa, E. J., 63.Warburg, O., 384.Ward, I. M., 108, 112.Ward, L. G. L., 126.Ward, P. F. V., 217.Ward, 12. B., 330.Ward, R. L., 76, 78.Ward, W. H., 459.Warnhoff, E. W., 289.Warren, C. K., 214.Warren, F. L., 289, 290.Warren, L., 330.Warsi, S. A,, 286.Wartburg, A. I?., 458.Warth, A. D., 255.Wartik, T., 124.Wasserman, A.. 241, 376.Wasserman, E., 238.Wasserman, H. H., 205,261, 275, 280, 296.Watanabe, H., 56, 63, 102,251, 259.Watanabe, T., 344, 488.Waterbury, G. R., 425.Waterman, H. I., 334.Waters, P. L., 460.Waters, T. N., 162.Waters, W. A., 333.Watkinson, J.H., 456.Watson, D. G., 258.Watson, E. J., 170.Watson, H. R., 157.Watson, J. D., 501.Watson, J. K. G., 48.Watson, W. H., 130.Watt, G. W., 129, 163.Watterson, K. F., 151.Watts, J. A., 155.Waurick, U., 452.Wawrzyczek, W., 417.Wawzonek, S., 223, 264.Weatherall, M., 392.Weatherby, T. L., 48, 55.Weaver, J. R., 56.Webb, H. W., 428.Webber, J. M., 343.Webber, P. J., 458.Weber, F., 402.Weber, J., 101.Weber, L., 325.542 INDEX OF AUTHORS’ NAMES.Webster, B., 225, 263.Webster, B. R., 279.Webster, D. E., 188.Webster, R. K., 413.Wechsler, M. T., 16.Wechter, W. J., 313.Weedon, B. C. L., 206,214,215, 218.Weger, &I., 69.Wehrli, H., 318.Weiche t, J . , 286.Weidenhagen, R., 332.Weidinger, A., 108.Weidmann, C., 312.Weidmann, €I., 342.Weigel, H., 330, 348.Weil, J.A., 73.Weimann, G., 296.Weinberger, A. J., 74.\Veinstein, A. , 437.Weinstock, B., 135.Weinstock, J., 176.Weisenborn, F. L., 313,Wciss, A., 125, 164, 232.Weiss, E., 148.TVeiss, H. V., 440.Weiss, J., 134.Weiss, M. J., 312.Wciss, R. J., 466.Weiss, S. B., 304, 361, 364.?Vciss, W., 158.Weissenfels, at., 202.Weissman, C., 288.Weissman, S. I., 75, 77, 79.Weissman, S. M., 355,357, 359.Weisz, H., 416, 417.Weldon, A. S., 116, 487.IVeller, A., 97.Wells, J., 436.Wells, M., 460.Wells, W. W., 307.JVelsh, H. L., 52.Welti, D., 437.Weltner, W., 63.Welvart, Z., 227.Wempen, I., 260, 395.Wende, C. V., 399.Wendenburg, J., 64.Wender, I., 144, 308.Wendlandt, W.W., 461.Wendler, N. L., 235, 277,Wendt, H., 80, 94.Wendt, M. W., 280.\Z’enkert, E., 237, 253, 286.Wenschuh, E., 140.Werder, F. V., 310.Werding, G., 125.Werner, I., 377.Werner, R. P. M., 143.Wernick, J . H., 485.Werum, L. M., 433.Wertz, J., 69.Wertz, J . E., 68, 69, 81.325.310, 314.West, A. C., 454.West, P. W., 416, 458.West, R., 127.West, T. S., 417, 447, 449,Westall, R. G., 369.Westheimer, F. H., 89.Wcstin, G., 235.Weston, G. O., 201, 313.Weston, R., 183.Wettstein, A., 310, 317,Weyer, I<., 125.Wcygand, F., 203, 282,TVhalley, E., 126.Whalley, W. B., 255.Wharton, P. S., 205.Wharton, L., 65.Wharton, W. W., 85.Wheatley, hl. S., 100.Wheatley, P. J., 488, 491,Wheeler, D. %I. S., 200.Wheelcr, 0.H., 313.Whelan, J. RI., 265.Whelan, W. J., 346, 348,Whiffen. D. H., 49, 52, 71,72, 73, 115, 272, 331.WhippIe, E. R., 159.Whistler, R. L., 334, 347.Whitby, F. J., 151.White, A. M. S., 200.White, D., 25, 47, 123.White, D. E., 252.White, D. M., 210, 224.White, E. F. T., 112.White, J. A., 122.White, J. C. B., 488.White, J. G., 468.White, J. R., 39.White, K. E’. &I., 81, 177,White, R. L., 58.Whitehouse, M. W., 347.Whitham, G. H., 217, 249,Whiting, D. A., 280.Whiting. M. C., 209, 211,212, 213, 221, 253.Whitnah, C. H., 438.Whittaker, D., 167.Whittaker, N., 384.Whittaker, V. P., 372.Whittam, R., 380, 385,Whittemore, W. L., 470.Whittle, E., 227.Whyman, B. H. F., 435.Wibaut, J. P., 264.Wiberg, K.B., 37, 55, 179.Wick, A. K., 226.Wickberg, B., 431.Wickham, D. G., 159.Wicki, W., 316.451.321.343.492.349, 377.190, 241.258.-386, 387, 389.Widmer, C., 398, 403.Wiechert, R., 310.Wiedcr, G. M.. 28.Wieland, I<., 44.Wieland, P., 310, 317, 321.Wiemann, J., 244.Wierzchowski, K. L., 304.Wiesenberger, E., 418.Wiesner, K., 99, 100, 102,Wiewiorowski, M., 283.Wiggins, L. F., 336.Wiggins, T. A., 46, 47, 52.Wightman, R. H., 201.Wikitin, E. E., 63.Wilbrandt, W,, 380, 381,Wilby. J., 177.Wildman, W. C., 283, 289.Wilen, S. H., 227.Wiles, D. M., 62, 76, 117.Wiley, D. W., 207, 232.Wiley, R. H., 216.Wilhelmi, K., 479.Wilke, G., 125.Wilkins, C. J., 131.Wilkins, D. Ii., 446.Wilkins, M. H. F., 301,303.Wilkins, T., 437.Wilkinson, D. I., 150.Wilkinson, G., 15, 62, 76,117, 144, 145, 146, 147,148, 149, 151, 152, 153,157, 158, 209, 233.200, 291, 294.392.Wilkinson, G. R., 46, 47.Wilkinson, M. K., 157, 467,Wilkinson, P. G., 44.Will, G., 495.Willard, J. E., 96.Willard, J. J., 341.Willbourn, A. H., 112, 113.Willemart, A., 210, 213.Willi, A. V., 84.Williams, A. E., 125, 221.Williams, A. F., 413.Williams, A. J., 55, 61, 65.Williams, C. H., 454.Williams, C. J., 264.Williams, D. E., 477, 480.Williams, D. H., 321.Williams, D. J., 432.Williams, D. L. H., 172.Williams, E. L., 163.Williams, F. V., 124.Williams, G., 57, 61, 485.Williams, G. H., 192.Williams, G. R., 397.Williams, H. L., 271.Williams, J., 120.Williams, J. P., 413.Williams, J. W., 107.Williams, L. A., 432.Williams, N. J., 268.Williams, (2., 48, 55.Williams, K. L., 120.472Williams, R. O., 246.MTilliams, R. T., 427.Williams, R. W. J., 300Williams, T. R., 173.Williams, V. R., 348.Williams, W. J., 441.Williamson, A. R., 295.Williamson, D. M., 310.Willis, C. J., 121, 128.Willis, G. M., 153.Willis, J . B., 450.Willis, R. C., 209, 224.Wilmarth, W. K., 68.Wilmshurst, B. R., 26.Wilson, A., 130.Wilson, A . D., 416, 440,Wilson, ,4. J. C., 493.Wilson, A. T., 330.Wilson, C. G., 484.Wilson, C.. L., 264, 410,Wilson, D. J., 30.Wilson, D. W., 429, 457.Wilson, E. B., 48, 56.Wilson, G., 112, 113.Wilson, G. L., 22.Wilson, H. N., 411, 424.Wilson, 13. R., 301.Wilson, I. H., 22.Wilson, J. D., 413.Wilson, I<. V., 369.Wilson, At. K., 48.Wilson, R. R., 323.Wilson, T. L., 217.Winans, J. G., 44.Windgassen, K. J., 288.Winefordner, J. D., 452.Winkhaus, G., 145, 147.Winia, R. A. F., 414.WinMer, H. J . S., 137.Winkler, W., 284.Winstein, S., 89, 167, 16S,173, 176, 198, 208, 223,230, 241, 244, 246.445.426, 427.Winter, G., 154.Winter, M., 344.Winterfeldt, E., 283.Winters, L. J., 268.Wirth, H. 0.. 225.Wirtz, H., 245.Wirwohl, B.. 135.Wiseman, W. A., 436.Wiss, O., 402.Witsiepe, W. K., 262.Wittenburg, E., 340.Witt, H. T., 96.Wittig, F. E., 18.Wittig, G., 191, 192, 204,207, 222, 227, 241, 245.Wittingham, D. J., 176.Wittmann, H., 453.Wittwer, H., 287.Wluka, D. J., 308, 309.Wnuk, R. J., 37.Wolfel, E., 464.INDEX OF AUTHORS' NAMEWoesmer, D. E., 98.Wohlaner, G., 480.Wohlfahrt, J., 311.Woidich, K., 431.Wojcicki, A., 143.Wojciechowski, B. WJ., 35.Wojtowicz, J. A., 37.Wolbach, R. A., 500.Wolf, A. P., 168, 271.Wolf, D. C., 205.Wolf, I?., 424.Wolf, H., 265.Wolf, K. H., 2'72.Wolfe, L. S., 376.Wolfe, S., 313.Wolfe, S. W., 433.Wolff, I. A., 217.Wolff, J., 392.Wolff, M. E., 315.M'olff, R. E., 63, 258.Wolfrom, Rf. L., 337, 439.Wolfsberg, M., 42, 69.Wollan, E. O., 467, 472.W'olovsky, R., 184, 231.Wong, E. L., 403.Wood, L. J., 117.Wood, P. R., 450.Wood, W. C., 96.Woodman, R. J., 369, 376.Woods, A. D. B., 470.Woods, C. W., 206.Woods, G. F., 224.Woods, L. L., 271.Woods, W. G., 210, 224.Woodward, A. E., 112,Woodward, L. A., 40, 51,Woodward, K. B., 280,Woody, R. W., 64.Wooldridge, I<. R., 201.Woolf, A. A, 425.\Voolf, L. A., 85.Worner, H. W., 153.Worrall, I. J., 125.Worrall, W. S., 242.Worthington, C. R., 465.Wright, A,, 348.Wright, A. N., 62, 76, 117.Wright, B. E., 325.Wright, C. V., 44.Wright, G. F., 56.Wright, H. B., 346.Wright, I. G., 341.Wright, J. R., 460.Wright, S. E., 325.Wright, W. G., 289, 290.Wronski, M., 417, 446, 449.Wu, C. Y., 400.Wunderlich, B., 11 1.Wunderlich, J. A., 121,Wurst, M., 433.Wyckoff, H. W., 496.Wyllie, G., 58.113.81, 125, 127.285, 493.344.543Wyman, J. E., 142.Wymore, C. E., 140.Wynder, E. L., 429.Wynne-Jones, W. F. I<.,Wynveen, R. A., 85.Xavier, J., 130.Yagi, K., 359.Yakel, H. L., jun., 157.Yakutin, V. I., 44.Yamada, A., 102.Yamada, S., 145, 161.Yamaguchi, M., 215.Yamakawa, H., 104, 105.Yamazaki, I., 92.Yanai, H. S., 493.Yanaihara, N., 225.Yang, D. H., 318.Yang, N. C., 202, 285, 318,Yao-Tseng, H., 229.Yardley, J . P., 258.Yaroslavsky, N. G., 46.Yaroslavsky, S., 56.Yashphe, J., 457.Yasuda, S. I<., 453, 460.Yasumoto, T., 108.Yates, K., 180, 339.Yates, P., 246, 248, 252,266, 268.Yats, L. D., 226.Yenik, J ., 452.Yeowell, D. A., 288.Yoe, J. H., 447.Yokoyama, N., 290.Yonetani, T., 399.Yonezawa, T., 184.Yoon, Y. I<., 473.Yorka, K. V., 319.Yorke, R. W., 220.Yoshihiro, Y., 343.Yoshimura, H., 291.Yoshino, Y., 158.Yoshizumi, H., 53,Yosini, S. J., 133.Yosizawa, Z., 337.Yost, D. hl., 131.Young, C. G., 71.Young, E. M., 433.Young, F. G., 380.Young, H. S., 154.Young, I. M., 384.Young, J. A., 128, 207.Young, S. T., 184.Young, T. F., 81, 135.Young, W. G., 167.Younger, P., 44.Youngs, C. G., 220.Yu, C., 299.Yu, C. T., 296.Yuan, H. Yu., 229.Yuan-Yau Chou, 448.Yumane, T., 87.Yung, N., 294.86.493544 INDEX OF AUTHORS’ NAMES.Yurygina, E. N., 187.Yuster, P. H., 70.Zabicky, J., 174.Zachariasen, W. H., 487.Zachrisson, M., 132.Zahn, E., 144.Zahnd, H., 427.Zahner, R. J., 451.Zaikin, I. D., 22.Zaikov, G. E., 431.Zaitsev, V. M., 467.Zak, B., 432.Zakharkin, L. I., 200.Zaki, M. R., 447.Zalkin, A., 476, 484.Zamecnik, P. C., 296, 298,Zamenhof, S., 300.Zamorzaev, A. M., 466.Zander, M., 184.Zandstra, P. J., 77.Zandy, H., 464.Zannetti, R., 161, 480.Zaslowsky, J. A., 37.Zaugg, H. E., 174, 208.Zauli, C., 193.Zawidzki, T. W., 20.361.Zechmeister, L., 213.Zeiss, H., 148.Zeldes, H., 71, 72, 74.Zelentsov, V. V., 62.Zeller, E. E., 24.Zeller, P., 280, 281.Zemann, A., 478.Zemann, J., 478.Zerahn, K., 386, 388.Zhdanov, G. S., 468.Zheludev, I. S., 466.Zholondkovskaya, T. N.,Zhuravlev, N. N., 485.Ziegenbein, W., 243.Zieger, G., 96.Zieger, H. E., 200.Ziegler, D. M., 397, 404.Ziegler, J. B., 305.Ziegler, K., 125.Ziegler, M., 425, 430.Ziegler, P., 312.Zielen, A. J., 141.Zielixiski, E., 438.Zillig, W., 302.Ziess, H., 128.Zimmerman, H. E., 232,424.246.Zimmerman, H. K., jun.,Zimmerman, J. B., 423.Zimmerman, S. B., 355.Zimmerman, S. M., 357.Zingales, F., 143, 148.Zinn, J., 460.Zinner, H., 337, 340.Zitomer, F., 457.Zocchi, M., 479.Zoltai, T., 473.Zook, H. D., 174, 208,Zorbach, W. W., 328.Zosel, K., 125.Zotterman, Y., 372.Zozulya, A. P., 79, 137.Zubay, G., 302, 303, 501.Zubyk, W. J., 439.Zuccaro, D. E., 484.Ziihlke, H., 155.Ziist, A., 279.Zuman, P., 337.ZvAEek, J., 286.Zweifel, G., 119, 196, 197,Zwolinski, B. J., 93.Zqka, J., 445.342.209.199

ISSN:0365-6217    

DOI:10.1039/AR9605700503

出版商:RSC    

年代:1960

数据来源: RSC

摘要:

INDEX OF SUBJECTS(dtmn. = determination)Absorption spectroscopy,atomic, 458.infrared, 459.ultraviolet, 456.visible, 456.Acepleiadylene, crystal structure of, 490.Acetals of carbohydrates, 335.Acetamide, N-methyl-, structure of, 487.Acetone-quinol, crystal structure of, 492.Acetyl groups, dtmn. of, in acetylatedAcetylacetone, masking properties of, 447.Acetylation in dtmn. of alcohols, 448.Acetylcholine in neural systems, 373.Acetylcholine bromide, structure of, 489.Acetylene, reaction of, with iron penta-Acetylene complexes, 147Acetylenes, 209.N-Acetylneuraminic acid, 377, 378.Acids, fatty, natural, 216.Acids, organic, characterisation of, 420.Acid-base titrations, 443.Aconitine, stereochemistry of, 290.Acridine 11, crystal structure of, 491.Actinides, 153.“Active transport ” in cells, 380.Adamantane, formation of, 245.Addition, elimination, and exchange re-Addition compounds, crystallography of,Adenine, 9-methyl-, bond lengths in,Adenines, synthesis of, 276.Adenosine triphosphatase, in active trans-port of cations, 391.Adenosine triphosphate, r81e of, in ionin neural systems, 375.Ajmaline, stereochemistry of, 286.Akuammicine, structure of, 288.Alcohols, lower aliphatic, separation of,Aldehydes, dtmn.of, 449.test for, 420.Alginic acid, 347.Alicyclic compounds, 238.Aliphatic compounds, 209.Alkaline-earth elements, collection of, 440.Alkaloids, 282.Alkyl phenyl ketones, heats of combustionof, 11.Allene, 1, 1-difluoro-, properties of, 212.Allenes, 212.Alternaric acid, structure of, 271.Altoside, structure of, 328.polyvinyl alcohol, 448.carbonyl, 148.actions, 168.483.495.transport in cells, 388.431.biosynthesis of, 282.Aluminium, compounds of, 124.pure, dissolution of, 414.separation of, from gallium, 422.Aluminium acetate, basic, structure of,oxide, temperature of ignition of, 440.differentiation of, 416.156.Amines, characterisation of, 421.Amino-acids, function of, in neural main-tenance, 367.tests for, 421.y-Aminobutyrate, metabolism of, in cere-bral functioning, 368.Aminopyridine, dtmn.of, 450.Amino-sugars, 341.periodate oxidation of, 341.Ammonia, solid, structure of, 473.Ammonia monohydrate, structure of, 473.Ammonium hydrogen sulphate, use of, inAnalytical chemistry, 410.Andrographolide, structure of, 255.Angelic acid, structure of, 487.Angustifoline, probable identity of, withAnhydrostrophanthidine, identity of, withAntimony, compounds of, 132.Stibine, heat of decomposition of, 2 1.Antimycin A, structure of, 275.Apoaspidospermine, structure of, 287.Arenobufagin, structure of, 328.Arginase in cerebral tissue, 369.Arginine phosphate in nerves, 369.Arginosuccinic acid in cerebrospinal fluid,“Aromatic,” use of the term, 223.Aromatic character, 183.fusions, 414.jamaicensine, 283.pachygenin, 326.369.compounds, 223.biogenesis of, 236.non-benzenoid, 223.substitution, electrophilic, 185.homolytic, 192.nucleophilic, 189.systems, complexes with, 149.Arsenic, compounds of, 132.Arsenite, dtmn.of, 444.Arsine, heat of decomposition of, 21.Artemisinamine, rearrangement of, 251.Arynes, 191.Aspidocarpine, structure of, 287.Astatine iodide, 137.Atomization, heats of, measurement of,Atroventin, 235.Aucubin, structure of, 280.Aureomycin, stereochemistry of, 498,Avicennin, structure of, 279,26.54546 INDEX OF SUBJECTS.Azacycloalkanes, N-methyl-, N-oxides of,ring cleavage of, 273.Azetidine, l-phenyl-, true structure of,262.Aziridinones (a-lactams), 260.Azoferrocene, preparation of, 232.Azoles, 265.Azomethane, thermal decomposition of,35.4,4’-tva~z~-Azopyridine N-oxide, structureof, 491.Azulene, metal complexes of, 149.Azulenes, 231.Baddeleyite, crystal structure of, 477.(&-)-Baikiain, synthesis of, 270.Baldulin, structure of, 25 1.Barium titanate, tetragonal, 468.Bases, minor, in ribonucleic acids, 299.Basic acid, structure of, 258.Benzene, resonance energy of, 183.j3-1,2,4,5-tetrabromo-, structure of, 490.Benzofurans, 277.Benzylisoquinoline alkaloids, 284.Benzyne intermediates, formation of, 226.Beryllium, dtmn.of, 439.Beryllium acetate, bonding effects in, 465.Betulenol, u- and Is-, structures of, 252.Bicyclo[2,2,2]octa-2,5,7-triene, stability of,2,3,5,6 - tetramethyl - 7,s - bis(trifluor0-intermetallic compounds of, 484.halides, 118.basic, structure of, 487.232.methyl)-, 232.Biogenesis of aromatic compounds, 236.Biological chemistry, 352.Biosynthesis’of nucleic acids, 352.of deoxyribonucleic acid, 353.Bismuth, compounds of, 132.dtmn.of, 442.extraction of, 424.separation of, 430.Bismuth ion, hydrolysis of, 133.salts, hydrolysis of, 80, 87.Tricyclopentadienylbismu t h , prepsr-ation of, 233.Bitter principles, 258.Borepin, synthesis of, 282.Boron, dtmn. of, in organic compounds,453.modifications of, 472.separation of, in steels, 424.Boron compounds, 118.cyclic, 281.Boron arsenide, 121.halides, 121.hydrides, 1 19.phosphide, 124.silicide, 124, 127.trioxide, heat of formation of, 20.Borate, dtmn. of, in presence of phos-Borate minerals, crystallography of,Boron-magnesium system, 119.phate, 444.485.Borides, crystallography of, 474.Borazole, preparation of, 123.Diborane, heat of hydrolysis of, 20.use of, in reduction of saccharides,uses and reactions of, 118.Diboron tetrachloride, heat of chlorin-Dirnethylborinic acid, 123.345.ation of, 21.Brein, structure of, 256.Bromides, organic, thermal decompositionof, 32.Bromine, formation of thiohypobromousacid from, 136.Bu fadienolides, 32 7.Bulnesol, configuration of, 251.Buphanitine, structure of, 289.cis-But-2-eneJ thermal isomerisation of,Butyl alcohols, heats of combustion of, 10.s-Butyl radicals, activated, production of,40.t-Butyl alcohol, decomposition of, in thegas phase, 32.t-Butyl cation, the, 166.Cadmium, dtmn.of, 440.test for, 418.Cadmium chloride, hydrolysis of, 87.dithizonate, extraction of, 425.hydrogen N- (hydroxyethy1)ethylene-diamine-NNN’-triacetate as primaryBisbiuretcadmium chloride, crystalBisethylenethioureacadmium thio-“ Calcichrome ” (CDTA), constitution of,Calcium, dtmn.of., 417.37.standard, 443.structure of, 481.cyanate, structure of, 480.417.test for, 417.Organocalcium halides, preparation of,118.Calorimetry, high-temperature, 18.Calycanine, structure of, 286.Calycanthine, structure of, 285, 493.( +)-Calycotomine, structure of, 284.Camphoketen dimers, structure of, 248.Camphor, x-bromo-, cis- and trans-, 249.Capsanthin, structure of, 214.Capsorubin, structure of, 214.Carbanions, 174.Carbenes, 175.preparation and reactions of, 222.Carbides, crystallography of, 474.Carbohydrates, 328.infrared spectroscopy of, 330.Carbon, dtmn.of, in organic compounds,Carbon dichloride (dichlorocarbene), pre-438, 450.paration of, 126.monoxide, dtmn. of, 417.tetrafluoride, heat of formation of, 21.Carbonyl chloride, test for, 421. .Thiocarbonyl fluoride, 126.test for, 417INDEX OFCarbonium ions, 1G6.Carbonyl compounds, 203.Carbonyls, 142.Carboxylic acids, 205.Cardenolides, 325.Carotene, a- and 6-, structure of, 214.Carotenoids, 213.Carotol, structure of, 251.Catalytic hydrogenation, 196.Catechols, %-amino-, oxidation of, 270.“ Catenane,” 238.Cativic acid, 6-0xo-, isolation of, 254.Cellulose, 347.Cerium, crystallographic forms of, 472.Cerium(Iv), extraction of, from solution,Charge-transfer reactions, study of, 77.Chartreusin, 235.Chelatometric titrations, 446.Chiapagenin, structure of, 324.Chlorine, hydrolysis of, 92.Chlorine hydrate, composition and struc-Perchloric acid monohydrate, crystalPerchloryl fluoride, ammonolysis of,crystallography of, 486.test for, 418.425.ture of, 135.structure of, 475.136.Chloroformates, alkyl, test for, 420.Chlorophyll, total synthesis of, 280.Cholegenin, structure of, 323.Cholesta-3,5-diene, irradiation of, 306.6a-Cholest-7-en-3-one, methylation of,Cholesterol, 22-hydroxy-, configuration of,24-methylene-, isolation of, 324.Choline chloride, structure of, 489.Chromans, 279.Chromatography, column, 427.Chromium acetate, basic, structure of,307.324.gas, 435.paper, 429.156.compounds, 156.tetrabromide, 156.extraction of, from solution, 425.Biphenylbistricarbonykhromium, crys-Dibenzenechromium, C-C bonds in, 149.Tricarbonylbenzenechromium, crystalCigarette smoke, separation of polycyclicCinerubin, aglycone from, 229.Cinobufagin, structure of, 328.Citric acid, ionisation of, 81.Cnicin, structure of, 259.Cobalt, separation of, 426.Cobalt(II1) complexes, oxidation of, 141.Cobalt compounds, 160.Chromium(rrr), dtmn.of, 445.tal structure of, 482.structure of, 482.aromatic hydrocarbons in, 43 1 .Bisacetylacetonecobalt (11) dihydrate,Cobaltinitrite solutions, anions in, 139.crystal structure of, 481.;UB JECTS. 547Cyclopentadienylcobal tcyclo-octatetra-ene, structure of, 233.trans - Dichlorobisethylenediamine-cobalt(II1) chloride, crystal structureof, 481.Dithiocyanatodipyridinecobalt, struc-ture of, 480.Tetracobalt decacarbonyl, structure of,142.Coenzyme Q (ubiquinone), 402.Colour centres in alkali halide crystals, 70.Conductance measurements, 84.Conessine, conversion of, into 18-amino-and 18-hydroxy-pregnan-2O-ones,315.Confertolin, structure of, 250.4-Conhydrine hydrobromide, structure of,Co-ordination number in aqueous solu-Copper, dtmn.of, 440, 442.493.tion, determination of, 138.extraction of, 425.potentiometric titration of, 446.test for, 418.compounds, 162.salicylate tetrahydrate, structure of,Copper (11) nitrate, anhydrous, crystallo-Copper ztioporphyrin 11, hyperfine split-ting from nitrogen atoms in, 77.487.graphy of, 479.gaseous, structure of, 162.salts, hydrolysis of, 87, 162.Dithiocyanatodipyridinecopper, struc-ture of, 480.Potassium periodatocuprate as a re-agent for easily oxidisable substances,420.Tetrakis - (4 - methylimidazole)copper(II)ion, configuration of, 162.17a-CorogIaucigenin, preparation of, 327.17cc-Corotoxigenin, preparation of, 327.Corrole, metallic derivatives of, 280.Coumarin, photodimers of, 278.Coumarins, 4-hydroxy-, syntheses of, 278.Coupling (and uncoupling) factors inCreatine phosphate, heat of hydrolysis of,Crocetin methyl ester, structure of, 214.Crystallography, 462.Cubeb camphor, structure of, 252.Cucurbitacin B, structure of, 258.Curarines, 288.Curvularin, structure of, 274.Cyanaropicrin, structure of, 259.Cyanogen fluoride, preparation of, 126.radical (CN), heat of formation of, 27.Cyanide, dtmn.of, 446.Cycloalkanes, heats of combustion of, 9.Cyclobu tane, 1,1,2,2-tetradeu tero-, ther-3,8-Cyclocamphor, 248.Cycloheptatrienyl anion, 246.radical, ionization potential of, 27.Cyclohexa-1,3-diene, irradiation of, 242.respiratory control, 407.19.mal decomposition of, 34548 INDEX OF SUBJECTS.Cyclohexane, ener,T difference betweenboat and chair forms of, 11.Cyclopentadiene complexes, 146.Cyclopentadienyl radical, ionization po-tential of, 27.Cyclopentyne, 241.formation of, 192.Cyclopropane, thermal isomerisation of,Cyclopropenium ions, 240.Cyclotetradecaheptaene, synthesis of, 231.Cyclotriacontapentadecaene, synthesis of,Cylindrocarpidine, structure of, 287.Cylindrocarpine, structure of, 287.L-Cystine, structure of, 494.dihydrobromide, structure of, 494.Cytidylic acid b.structure of, 495.Cytochromes, 398.Damage by radiation in inorganic ionicDecalin, acetylation of, 244.cis- and trans-, stability of, 8.9-methyl-, cis- and trans-, stability of, 8.Decalin-9-carboxylic acid, formation of,242.( f)-Dedimethylamino-6-demethyl-6, 12a-dideoxychlorotetracycline, synthesisof, 228.22-Dehydrocholestero1, occurrence of, 324.Dehydroelsholtzione, structure of, 264.identity of, with naginata ketone, 264.Dehydrogenation, 201.Deltaline, identity of, with eldeline, 291.Deoxypithecolobine tetratoluene-p-sul-phonate, synthesis of, 294.Deoxyr ibonucleic acid, bios yn t hesis of ,353.Deoxyribose. structure of, 494.Deoxy-sugars, 335.Desilylation, 188.Deuterium isotope effects, 181.Diacetylhydrazine, structure of, 488.Diamonds, synthetic, nickel in, 472.Diazines, 272.Diazocyclobutane, reactions of, 241.Diazopyrazoles, formation of, 265.1.2 : 8,9-Dibenzacridine, C-H bond lengthin, 465.Dibenzofuran-2-sulphonic acid as reagentfor animes, 421.for amino-acids, 422.Di-t-butyl peroxide, unimolecular de-composition of, 35.1,3-Di-t-butylcyclohexane, equilibriumbetween cis- and trans-isomers of, 11.trans-1,2-Dichloroethylene, isomerisationof, 35.6-Didehydro-~-fructose, formation of, 332.Dielectric loss, 61.saturation, 60.3,3‘-Diethylthiacarbocyanine bromide,17c~-Digitoxigenin, identity of, with mena-37.231.crystals, 71.crystal structure of, 492.begenin, 327.5,lO-Dihydro-5,1O-dimethylarsanthren di-bromide and di-iodide, crystal struc-ture of, 492.S,S-Dihydro-oxepin, synthesis of, 274.Diketones chelated to transition-metal1, l-Dimethylcyclopropane, thermal de-1,2-Dimethylcyclopropane, thermal iso-Dimethylglyoxime, structures of metalDimethylmercury, thermal decompositionDiphenyl sulphone, 4,4’-dichloro-, crystalDiphenylacetic acid, dissociation energy,l,%Diphenyiethane, 1,1,2,2-tetrafluoro-,Diphenylglycollaldehyde phenylhydra-Diploicin, 235.Dipole moments, 54.ions, reactions of, 138.composition of, 37.merisation of, 37.complexes of, 480.of, 33.structure of, 490.D(Ph,CH-CO,H), in, 27.crystal structure of, 490.zone, dehydration of, 275.effect of isotopic substitution on, 59.sign of, 58.Dipropylcyclopropenyl cation, the, 229.Disaccharides, 344.Diterpene alkaloids, 290.Diterpenes, 253.Di-p-xylylene, distorting vibrations in,Drimenin, structure of, 250.Dye indicators, new, 441.Echinulin, structure of, 276.Edelamblygonite, crystal structure of,Eldeline, identity of, with deltaline, 291.Electrochemical methods applied to fastElectron spin resonance, 68.Electron-transport system, in respiratoryElectronic spectra, vibration-rotationElectrophoresis, 432.Elements in organic compounds, dtnin.of,Elimination, bimolecular nucleophilic, 177.Emetine, structure of, 284,“ Emich,” the, definition of, 411.Emission spectroscopy, 453.Episulphides, formation of, 336.Epoxides, dtmn.of, 449.Erbium chloride solutions, complexes in,wesoErythrito1, structure of, 488.Esters of carbohydrates, 339.Ether, test for, 419.Ethers of carbohydrates, 338.Ethyl 2,4-dimethylpyrrole-3-carboxylate,bromination of, 263.469.structure of, 491.477.reactions in solution, 99.chain, 395.components of, 397.analyses from, 43.450.reduction of, 336.80INDEX OF SUBJECTS. 549Ethylene, dissociation energy of C-H bondtrans-l,2-dichloro-, isomerisation of, 35.tetracyano-, metal complexes of, 139.in, 26.Ethylene sulphides, 261.Eucarvone, irradiation of, 249.Europium sulphides, crystal structure of,Evodone, structure of, 277.Exaltolide, synthesis of, 274.Excitation of nerve cells, 371.478.Faraday, value of the, 79.Faraday effect, the, 64.Fast reactions in solution, 90.Ferrocenyl cyanide, preparation of, 233.Ferroelectrics, 468.Five-membered rings, saturated, pseudo-rotation in, 12.Flame photometry, 454.Flash photolysis applied to fast reactionsin solution, 96.Flow techniques for fast reactions insolution, 9 1.Fluoramines, formation of, 128, 129.Fluorene derivatives, test for, 419.Fluorescence measurements applied toFluorimetry, 455.Fluorine chlorate, thermal decompositionchlorite, thermal decomposition of,Fluoride, spot test for, 417.fast reactions in solution, 97.of, 36.36.“ Fluorodene,” 229.Force constants, 49.Formaldehyde, mechanism of transforma-Formic acid, gaseous, thermal decom-Friedelin, structure of, 257.lF- and 6a-~-~-Fructosylsucrose, occur-Fumagillin, structure of, 261.Functional-group determination, 448.Furans, 264.Furantetracarboxylic acid, pK, of, 264.Furfuraldehyde, 5-hydroxymethyl-, form-tion of, into sugars, 331.specific test for, 420.position of, 33.rence of, 344.ation of, 264.Galactosamine in gangliosides, 377.Gallium, dtmn.of, 440.extraction of, 424.separation of, from aluminium, 422.test for traces of, in aluminium, 417.Gallium halides, 125.oxide, structure of, 125.Gangliosides in cell membranes, 376.preparation of, 377.properties and structure of, 378.Gas chromatography, 435.Geigerin, configuration of, 251.Geissospermine, fission products of, 288.General and physical chemistry, 7.Germanium, compounds of, 127.dtmn. of, 444.separation of, 434.Germine, esters of, 293.Gibberellin A,, structure of, 277.Gibberellins, 256.Gibberone, synthesis of, 254.D-Glucose, degradation of, 333.Glucose, function of, in neural main-Glycerides, natural, structure of, 220.P-Glycine, bond lengths and angles in,Glycine complexes of zinc and cadmium,Glycines, test for, 420.Glycogen, 348.Glycol-cleaving reagents, 337.Glycolysis, effect of, on movements of ionsGlyoxal, test for, 420.Gold, extraction of, from solution, 425.spot test for, 418.Gravimetric analysis, 439.Griseofulvin, synthesis of, 235.total synthesis of, 277.Guaiol, configuration of, 251.Guanidines, function of, in neural main-oxidation of, 333.tenance, 367.494.crystal structure of, 452.across cell membranes, 384.tenance, 368.Haematin-globin reaction, rate of, 92.Haemoglobin, crystallography of, 499.Halides, 206.alkyl, test for, 420.crystallography of, 475.Halogen titrations, 444.Halogens, dtmn. of, in organic compounds,Halogenation, 187.Heats of combustion in fluorine, 16.in oxygen, 8.of hydrocarbons, 8.452.Hemicelluloses, 349.Heteroaromatic compounds, 193.Heterocyclic compounds, 259.Hexahydroindane, cis- and trans-, stabilityHexasaccharide from human milk, 344,Hinokiic acid, structure of, 252.Hinokiol, structure of, 255.Hinokione, structure of, 255.Hippeastrine, stereochemistry of, 290.Holarrhimine, conversion of, into 18-hydroxyprogesterone, 316.D-Homoannulation of 16a, 17a-dihydroxy-20-ketones, 3 14.Homolycorine, configuration of, 290.Hopanone, hydroxy-, configuration of, 257.Hortiacine, structure of, 285.Hortiamine, structure of, 285.Humilinone, structure of, 259.Hydrates, crystallography of, 478.Hydrazine, diacetyl-, structure of, 488.of, 8.345.tetrasilyl-, 127550 INDEX OF ~-Hydrides of the transition elements, 152.Iiydroboronation, 196.Hydrogen, catalytic activation of, 117.dtmn.of, in organic compounds, 438,Hydrogen atoms, reaction of, with iso-Hydrogen bond, the, 116.Hydrogen chloride monohydrate, struc-cyanide, tetrameric, structure of,peroxide dihydrate, structure of, 133.450.propyl radicals, 40.ture of, 473.125, 221.Hydrogenation, catalytic, 196.Hydrogen-isotope exchange, 185.Hydroxides, crystallography of, 477.22-Hydroxycho1estero1, configuration of,Hygrine, synthesis of, 283.Hypoartemisin, 251.Hypoxanthines, synthesis of, 276.Ibogaine, stereochemistry of, 493.Ice, polymorphs of, 473.Imidazoles, formation of, 267.Indane, heat of hydrogenation of, 9.Indene, heat of hydrogenation of, 9.Indium, dtmn.of, 440.Indoles, 275.Infrared spectroscopy of sugars, 330.Initiation of discharge of membraneInorganic chemistry, 115.Intensities, infrared, 51.Intermetallic compounds, crystallographyIodine, distinction of, from chloride and324.halides, reactions of, 125.potential, 372.complexes, mechanism of reactions of,140.of, 484.bromide, 418.halides of, 136.‘‘ Iodosobenzene dinitrate,” structurePeriodate, test for, 418.Potassium periodatocuprate as a re-agent for easily oxidisable substances,420.Ion movements in cells, inter-reIation of,383.Ion-exchange, 433.Ion-pair formation, study of, by electronIons, excited, decomposition of, 42.Ions of transition-metal, rare-earth, andtrans-,3-Ionylidenecrotonic acid, structureIridium, volatility of, in oxygen, 159.Iron, compounds of, 169.sensitive test for, 418, 426.Iron(rr) oxide, nature of, 159.Iron(m), reduction of, 434.of, 137.spin resonance, 77.in solution, 79.non-classical, 229.actinide series in single crystals, 68.of, 494.separation of, from iron(II), 426.SUBJECTS.Iron(m) acetate, basic, structure of, 156.oxide, crystalline, precipitation of, 442.Iron pentacarbonyl, reaction of, withIsobalfourodine, structure of, 284.“ Isocamphorquinone,” formation of, 248.Isocholegenin, structure of, 323.Isoclovene, structure of, 252.Isodrimenin, structure of, 250.Isoindigo, crystal structure of, 492.cis-Isoketopinic acid, formation of, 249.Isophyllocladene, structure of, 255.Isoprenoids, 215.Isopropyl radicals, reaction of, withIsoquinoline alkaloids, 284.Isoquinolines, 276.Isorenieratene, synthesis of, 215.Isosteviol, structure of, 255.Isoxazolidines, formation of, 263.2-Isoxazolines, 3-substituted, formationacetylene, 148.hydrogen atoms, 40.of, 267.Jamaicensine, probable identity of, withJamaidine, structure of, 283.Jatamansone, identity of, with valeranone,(+)- Junenol, configuration of, 250.(-)-Kaurene, structure of, 255.Ketones, dtmn.of, 449.Kinetic measurements in solution, 89.Kinetics of niigration of ions acrossKogagenin, structure of, 323.Lactobacillic acid, crystallographic struc-Lactones, steroidal, 325.Lagosin, structure of, 221.Lanthanides, 153.Lanthanum deuteroxide, crystal structureof, 477.Lead, compounds of, 128.Lead(I1) salts, hydrolysis of, 87.Limonin, structure of, 258.(+)-Linalool, configuration of, 216.Lipids, role of, in respiratory chain,Lithium aluminium hydride, use of,chloride, separation of, from sodiumangustifoline, 283.249.membranes, 38 1.ture of, 486.separations of, 430.dtmn. of, 424, 442.separation of, 430.401.199.chloride, 424.vapour, dimeric, 117.Longifolene, structure of, 252.Lorandite, crystal structure of, 478.Lunacrinol (lunasia 11), structure of, 284.Lunamarine, structure of, 2 13.Lupinane alkaloids, 283.Lutidines, heats of isomerization of, 13.Lycopodium alkaloids, 291.Lycorenine, configuration of, 290INDEX OF SUBJECTS.551Maculosidine, structure of, 284.Maculosine, structure of, 284.Magnesium, dtmn. of, 439.perchlorate, dtmn. of water in, 415.Magnesium-boron system, 119.Magnetic materials, structures of, 467.susceptibilities, 62.Maintenance, neural, 367.Malonimides, formation of, 261.Manganese, compounds of, 158.D-Mannose, preparation of, 332.Manoyl oxide, stereochemistry of, 255.oxo-, structure of, 255.Marinobufagin, structure of, 328.Megalosaccharide, use of the term, 346.Membrane hypothesis, the, 382.potential in brain cells, 370.Menabegenin, identity of, with 17a-di-gitoxigenin, 327.Menthofuran, formation of, 277.Mepacrine, dtmn.of, 448.Mercaptomethylthiirans, 26 1.Mercury, dtmn. of, 440, 446.in organic compounds, 453.extraction of, from solutions, 426.Mercuric chloride complexes, 88.oxycyanide, formation of, 164.solutions, standardisation of, 445.(A)-Mesembrane, synthesis of, 290.Mesembrenine, structure of, 290.Mesembrine, structure of, 290.Metabolism, effects of, on movements ofions across cell membranes, 384.Metagenin, structure of, 324.Metal carbonyl fluorides, 143.Metal complexes, crystallography of, 479.Metal-metal bonding, 161.Metallocenes, 232.Methacoylate resins, test for, 420.Methane, equilibrium bond length in, 46.2,2’-dinitrodiphenyl-, reduction of, 273.N-Methylacetamide, structure of, 487.Methylbixin, “ natural,” structure of, 214.hlethylcyclopropane, thermal decomposi-tion of, 36.9-Methyldecalin, cis- and trans-, stabilityof, 8.cis - 1 -Methyl - 2,6 - diphenyl- 4 - piperidoneoxime, optical resolution of, 270.4 -Methyl - 1,2 -dithiacyclopent - 4 - ene - 3 -thione, crystal structure of, 492.hlethylene, addition reactions of, to aC-C bond, 38.radical, electronic spectra of, 45.Methylenebisnitrosohydroxylamine, struc-ture of, 488.24-Methylenecholesterol, occurrence of,324.Methyloctadecanoic acids, structures of,486.Methyl phenyl sulphide, dissociationenergy, D(PhS-Me), in, 27.( -)-Methylisopulegone, absolute configur-ation of, 248.Mevalonic acid, preparation of, 2 18.Microbial permeases, 394.Mirene, structure of, 255.Mitochrome, 408.Molecular compounds, crystallography of,Molecules, optical, electrical, and mag-Molybdenum, compounds of, 156.492.netic properties of, 53.K-oxide, structure of, 156.separation of, 426.sulphides, 157.tetrachloride, 157.Hexafluoromolybdates-(Iv) and -(v),stability of, towards hydrolysis, 157.Molybdenum(w), dtmn.of, 445.Monosaccharides, degradation of, 333.methods of separation of, 328.oxidation of, 333.reduction of, by diborane, 345.synthesis of, 331.Monoterpenes, 248.Munduserone, structure of, 279.Muscaridine, structure of, 222.Myoglobin, crystallography of, 497.Naginata ketone, identity of, with de-hydroelsholtzione, 264.Naphthalene, triplet state of, 78.Neoajmaline, structure of, 286.Neohelenalin, structure of, 251.Neoline, structure of, 291.Neoruscogenin, structure of, 323.Neotigogenin, synthesis of, 323.Neptunium, separation of, 426.Nerolidol and its hydro-derivatives, pre-paration of, 216.Nerves, efflux of sodium from, 390.Neurochemistry, 367.Neurone membrane, electrical resistanceNickel, complex cyanides of, 161.by periodates, 337.of, 370.compounds of, 160.dtmn.of, 440.Bis-salicylaldimine complexes ofnickel@) and copper(II), crystalstructure of, 482.Tetramminenickel nitrate, crystal struc-ture of, 481.2,2’,2” - Triaminotriethylaminenickel (IT)dithiocyanate, crystal structure of,481.Trisethylenediaminenickel (11) nitrate,crystal structure of, 481.Nimbiol, synthesis of, 253.Niobium, dtmn. of, 441.separation of, from tantalum, 425, 428.Niobium compounds, 155.pentachloride, heat of formation of, 22.sulphides, 155.Niobiu m-sulphu r system, 478.Niobates, poly-, 155.Sodium niobate, space group of, 469.Nitrogen, dtmn.of, in organic compounds,a- and 8-, space groups of, 473.in rocks, etc., dtmn. of, 414.451552 INDEX OF SUBJECTS.Nitrogen compounds, 128.spot test for, 419.Nitrophenols, o- and 9-, test for, 421.Nitrosoisobutane (dimeric), trans- thermalNitrosomethane (dimeric), trans- thermalNitrosyls, 144.Nitrotoluenes, mono-, test for, 421.Nomulin, structure of, 258.Non-aqueous titrations, 448.Non-crystalline materials, structure of,Norbornadiene, peroxidation of, 246.Norbornadien-7-yl cation, the, 168, 230.Norbornane, nitration of, 244.Norbornan-7-one, 2-hydroxy-, prepar-Norbornene, epoxidation of, 245.Norborn-5-ene-2-carboxylic acid, electro-18-Nor-steroids, partial synthesis of, 31 1.Nuclear magnetic resonance applied tofast reactions in solution, 97.Nuclear quadrupole coupling, 67.Nucleic acids, 294.Nitrous acid, test for, 417.decomposition of, 33.decomposition of, 33.470.ation of, 245.lysis of, 245.biosynthesis of, 352.isolation of “ native,” 298.Nucleosides, 294.Nucleotide anhydrides, 297units, terminal addition of, to RNA, 361.non-terminal incorporation of, intoRNA, 363.Nucleosides, 296.Obacunone, structure of, 258.Octopole moments, 62,Odyssic acid, structure of, 211.Odyssin, structure of, 21 1.Olefinicomplexes, 145.Olefinic compounds, 2 13.Olefins, test for, 419.Oleic acid, dtmn.of, 447.Oligosaccharides, 344.use of the term, 346.Optical rotatory dispersion, 63.Organic chemistry, 165.theoretical, 166.poly-, 298.compounds, dtmn. of elements in, 450.matter, destruction of, 414.radicals, oriented, in crystals, 71.structures, crystallography of, 48 6.Organometallic compounds of the transi-tion elements, 150.Osmium, compounds of, 159.9-Oxa-lO-bora-anthracene, 10-hydroxy-,preparation of, 281.Oxazoles, 267.Oxazol-5-one, 4-hydroxymethylene-2-phenyl, rearrangement of, 267.Oxetanes, formation of, 262.Oxidation in organic chemistry, 202.of carbohydrates by periodate, 337.volatility of, in oxygen, 159.Oxidative phosphorylation, 405.Oxides, crystallography of, 476.Oxinates, partition of, between water andOxonitine, structure of, 291.Oxygen, dtmn.of, in organic compounds,Oxygen atoms, addition of, to olefins, 40.Pachygenin, identity of, with anhydro-strophanthidin, 326.Palladium, compounds of, 161.dtmn. of, 441.heat of sublimation of, 26.separation of, 427.Parthenin, structure of, 259.Periodate oxidation of amino-sugars, 34 1.Peroxides, crystallography of, 477.Petasin, configuration of, 250.Phenanthridine alkaloids, 289.Phenol, 5-methoxp-2-nitroso-, structurePhenols, 234.Phenylacetic acid, dissociation energy,Phenylarsonic acid, structure of, 487.l-Phenylazetidine, true structure of, 262.2-Phenylisatogen oxime, crystal structureof, 491.Phosphagens, function of, in neural main-tenance, 368.Phosphatidic acid, as carrier for transportof cations across cell membranes, 393.Phosphocreatine in brain, 369.Phosphorus, compounds of, 129.chloroform, 424.451.heterocycles, 27 1.of, 490.o-amino-, formation of, 264.D(PhCH,-CO,H), in, 27.dtmn.of, in organic compounds, 453.extraction of, 424.Phosphides of platinum-group metals,Phosphine, triphenyl-, bond dissoci-Phosphonitrilic chloride, heats of com-Phosphonitrilic chlorides, structure of,in presence of borate, 444.159.ation energy in, 15.bustion of polymeric forms of, 15.130.Phyllocladanol, structure of, 255.u-Picoline, formation of, 269.Picrolichemic acid, 235.Pimaric acid, absolute configuration of,Pinene, u- and Is-, hydroboronation of, 248.Piperidines, 268.Platinum, compounds of, 161.heat of sublimation of, 26.volatility of, in oxygen, 159.tetrafluoride, reaction of, with sulphurPlatinum-group metals, phosphides of,Plutonium, separation of, 426.Pluviine, stereochemistry of, 290.(+)-Podocarpic acid, total synthesis of,254.tetrafluoride, 160.159.nrrINDEX OF SUBJECTS.553Polarisabilities, 65.Polonium, extraction of, 425.separation of, 430.fluoride, 135.Polyacetylenes, 2 1 1.Polycyclic compounds, aromatic, 228.Polyenes, cyclic, 231.Polymers, amorphous states of, 110.large, 184.tions, 103.chain conformation of, in dilute solu-chemical structure of, 113.dynamic properties of, 112.elasticity of, 110.phase separation in, 108.physical properties of, 102.rheological properties of, 106.solutions of, 102.static properties of, 111.ultracentrifugation of, 107.chain configuration of, 108.crystalline state of, 108.melting phenomena in, 110.single crystals of, 109.Polymers in bulk, 108.Polynuclear hydrocarbons, crystal struc-Polynucleotide phosphorylase, 359.Polypyrroles, 280.Polysaccharides, 345.Potassium, dtmn. of, 430.Potassium hydrogen bisphenylacetate,crystal structure of, 465.hydroxide, structure of, 117.ion, concentration of, in brain cells,monogermanide, structure of, 473.ture of, 489.immunological specificity of, 350.reduction of, by diborane, 345.solubility of, in ethers, etc., 117.370, 380.Precipitation from homogeneous solution,Precipitation titrations, 444.Protactinium, separation of, from thorium,Proteins, crystallography of, 495.Protoverine, structure of, 293.Psoralidin, structure of, 278.Pteridine, 2-hydroxy-, oxidation of, 277.Pteridines, 276.Purines, 276.Purprigenin, structure of, 324.Purprogenin, structure of, 324.Pyrazine, rotational analysis of, 49.Pyrazole, crystal structure of, 491.Pyrethrosin, revised formula for, 249.Pyridine, test for, 420.2-isothiocyanato-, dimeric, 269.pentduoro-, synthesis of, 269.substituted, tautomeric equilibria in,194.I-( 2-Pyridylazo) -2-naphthol (PAN), useof, 424, 425.Pyrimidine, crystal structure of, 491.Pyrimidines, 273.441.426.Pyridines, 268.4-Pyrones, acylation of, 271.Pyrroles, synthesis of, 262.Pyrromycin, aglycone from, 229.Pyrylium salts, a new route to, 272.Quadrupole moments, 62.Qualitative analysis, inorganic, 416.Quassin, structure of, 279.Quinol-acetone, crystal structure of,Quinoline, bromination of, 276.diazo-, 263.organic, 419.402.8-acetoxy-, use of, 442.8-mercapto-, structure of, 276.Quinoline alkaloids, 283.Quinolines, 276.Quinones, 234.R Factor, 408.Radiation, damage by, in inorganic ionicRadicals in solution, spectra of, 75.X-Ray methods of analysis, 456.Reaction calorimetry, 17.Reactions a t a carbonylic and relatedRecovery of neural systems, 371, 375.Redox pump theory in “ active transport,”Redox titrations, 444.Relaxation methods applied to fast re-Respiration, effect of, on active transport,Retamine, structure of, 283.Rhenium, compounds of, 158.Rhetsinine, structure of, 285.Rhodium, separation of, 427.Rhodium monosilicide, structure of, 473.in oxidative phosphorylation, 408.crystals, 7 1.centres, 178.387.actions in solution, 92.386.volatility of, in oxygen, 159.tetrafluoride, reaction of, with sulphurtetrafluoride, 160.Rhoeadine, structure of, 284.Ribonuclease, structure of, 500.Ribonucleic acid, biosynthesis of, 359.Ribonucleic acids, minor bases in, 299.Rubidium dihydrogen citrate, stereo-Ruthenium, compounds of, 159, 160.chemistry of, 487.separation of, 427.volatility of, in oxygen, 159.(+)-Salsoline, structure of, 284..Sandaracopimaric acid, structure of, 254.Santonins, 250.Sapogenins, steroidal, 323.Sarcostin, structure of, 324.Sarpagine, skeletal structure of, 286.Scandium, dtmn. of, 440.Scandium group, 153.Scymnol, structure of, 325.Sea water, dtmn. of trace elements in,Sedinine, position of double bond in, 283.434554 INDEX 0 1Selagine, structure of, 292.Selenium, dtmn. of, in organic compounds,453.separation of, 430.test for, 417.Selenium compounds, 135.Sepeerine, structure of, 285.Sericetin, 280.L-Serine phosphate, C-N bond length in,494.Sesquiterpenes, 249.Shelloic acid, structure of, 252.Silicon, compounds of, 126.extraction of, 424.heat of sublimation of, 26.Silicon boride, 124, 127.tetrafluoride, heat of formation of, 21.Disilane, 126.Disilyl ether, Si-0-Si skeleton in, 49.Silica, precipitation of, 440.Silicate minerals, crystallography of,Silicates, decomposition of, a t roomSiliceous materials, decomposition of,Tetrasilylhydrazine, 127.dithizonate, extraction of, 425.halides, selective precipitation of, 442.oxinate, extraction of, 425.salts, hydrolysis of, 87.Siphulin, structure of, 279.Sodium, dtmn.of, 444.Sodium fusion test, improvement upon,Sodium ion, concentration of, in braincells, 370, 380.Sodium-potassium eutectic, solubility of,in ethers, 117.Sodium hydrogen diacetate, bondlengths in, 465.Solvent effects, 208.extraction, 423.Solvolysis, 172.Spectrometry, nuclear magnetic resonance,485.temperature, 445.414.Silver, spot test for, 418.Silver compounds, 163.solubility of, 88.419.80.Raman and infrared, 81.X-ray, 80.relaxation, 80.visible and ultraviolet, 82.Spectroscopic analysis, 453.Spectroscopy, absorption, 456.Spectroscopy and molecular structure, 42.Starch, 348.Stearic acid, methyl ester, crystallo-graphy of, 486.Sterculic acid, preparation of, 217.synthesis of, 239.Stereochemistry, 247.Steroid sapogenins, 323.Steroids, 305.emission, 453.naturally occurring, 324.SUBJECTS.Steroids, l6-0xo-, bromination of, 31 1.18-oxygenatedJ partial synthesis of, 315.total synthesis of, 318.Steviol, stereochemistry of, 255.Stibnite, structure of, 132.Streptimidone, structure of, 270.Strophanthin as inhibitor of active trans-Sublimation, heats of, measurement of, 26.Substitution, bimolecular nucleophilic,port, 392.176.elec trophilic, 225.homolytic, 227.nucleophilic, 226.Sugar derivatives containing nitrogen,‘‘ T-Sulphonamidine,” as chelating agent,Sulphonation, 185.Sulphur, compounds of, 133.dtmn.of, in organic compounds, 452.elementary, test for, 417.fluorides of, 133.Sulphur tetrafluoride, heat of formationof, 21.uses of, 206.Bisulphite solutions, anions in, 134.Hexasulphur di-imide, 134.Hexathionic acid, preparation of, 135.Peroxytetrasulphates, formation of, 135.Sulphate, dtmn.of small amounts of,Sulphides, crystallography of, 478.Sulphuric acid, conductance of, 85.aqueous, heat of formation of, 13.Thiocarbonyl fluoride, 126.Trimethylsulphonium borohydride, 1 34.Symmetry and space-group theory, 466.Tantalum, separation of, from niobium,343.440.445.425, 428.heat of formation of, 22.Technetium, compounds of, 168.Teichoic acid, 361.Tellurium, separation of, 430, 434.Tenuazonic acid, formation of, 264.Tercyclopropane, l-methyl-, 238.Tetanus toxin, action of, 376.Tetracyanoethylene, metal complexes of,Tetracycline antibiotics, 228.1 , l12,2-Tetradeu terocyclobu tane, thermaldecomposition of, 34.Tetrahydro-3,4-dioxofuranJ synthesis of,265.Tetrahydrofuran, chlorination of, 265.2,3,5,6 - Tetramethyl - 7, 8 - bis(trifluor0 -methyl) - bicyclo[2,2,2]octa - 2,5,7 -triene, 232.Thalicberine, structure of, 285.Thallium, dtmn.of, 440.Dimethylthallium ion, 125.Thallic halide solutions, complex ionspentachloride, aminolysis of, 156.139.structure of, 488.in, 81INDEX OFThelephoric acid, structure of, 278.Thelepogine, structure of, 294.Thermal methods of analysis, 459.Thermal motion in crystals, 469.Thermochemistry, 7.Thermodynamic measurements, 86.Thian, 5-chloro-2-chloromethyl-, form-3-Thiazoiines, formation of, 268.Thietan, 2-hydroxy-, 26 1.Thioacetamide, structure of, 487.Tliionia-cation, the, 195.Thiophens, 265.Thiopyrans, 273.Thorium, extraction of, from solution,ation of, 265.425.heat of sublimation of, 26.separation of, from uranium and prot-actinium, 426.Thujopsene, structure of, 252.Thulium di-iodide, 153.Thymine, l-methyl-, bond Ierigths in, 495.Thyroxine, as uncoupling factor in re-Tiglic acid, structure of, 487.Tigogenin, synthesis of, 323.Tin, compounds of, 128.spiratory control, 408.test for, 417.Hexahydroxystannatcs, crystal struc-Tetrakistriphenylstannyloxytitanium,tetrachloride, aminolysis of, 154.Dicyclopentadienyltitaniumdicarbon yl,Tetrakistriphenylstannyloxytitanium,Tricyclopentadienyltitanium, 140.ture of, 477.154.Titanium compounds, 154.149.164.structure of, 233.Titrimetric analysis, 442.&-Tocopherol, structure of, 279.a-Tocopurple, structure of, 270.o-(Toluene-p-su1phonamido)aniline (T-sulphonamidine) as chelating agcnt,440.Transition elements, 137.hydrides of, 152.organometallic compounds of, 150.Trianhydrostrophanthidin, structure of,Trichothecin, stereochemistry of, 252,Tricyclene, n-bromo-, conversion of, intoTricycline sulphate, space group of, 468.Triglycine sulphate, forms of, 494.Trimethylammonium dicyanomethylide,Triphenylmethyl chloride, nature of, inTriphenylphosphine, bond dissociationTrisethylenediaminenickel(r1) nitrate, con-“ Trishornocyclopropenyl ” cation, 223.326.253.n-bromo-camphor, 248.stability of, 222.liquid sulphur dioxide, 83.energy in, 15.figurations in, 140.IUBJBCTS.5%Triterpenes, 256.“ Tritosylsucrose,” constitution of, 345.Tropan-3-one, 68,7cc-dihydroxy-, opticallyTropolones, 230.Tungsten, compounds of, 157.Tylophorinine, structure of, 293.Ubiquinone (coenzyme Q), 402.Umbellularic acids, configurations of, 240.Unimolecular reactions, experimentalactive, synthesis of, 280.Dibenzenetungsten, preparation of, 233.work on, 31.gas-phase, 28.theory of, 38.Unithiol (2,3-dimercaptopropanesulphon-Unsaturation, dtmn. of, in fats and oils,Urea, function of, in neural maintenance,Uranium, separation of, from iron andate), use of, 446.449.368.vanadium, 428.from thorium, 426.Uranium(vr), reduction of, to uranium(w),Uranium dioxide, fusion of, 153.nitrate hexafiydrate, structure of, 153.Uranyl carbonate, preparation of, 153.l7a-Uzarigenin, preparation of, 327.Valeranone, identity of, with jatamansone,Vanadium, dtmn. of, 441, 445.extraction of, in solution, 426.Vanadium(Iv), dtmn. of, 445.separation of, 425, 428.Vanadium(v), reduction of, to vanad-Vanadium dioxynitrate, 155.Dicyclopentadienylvanadium ( II I) chlor-Vanadates, poly-, stable anions in, 155.17aporization, heats of, measurement of,Varrentrapp reaction, the, 218.Vevatrztm alkaloids, 292.Violacein, synthesis of, 275.Viruses, structure of, 501.Vitamin D, 321.444.249.ium(m), 444.ide, 149.26.Water, dtmn. of, in magnesium per-chlorate, 4 15.low conductivity of, 79.Yangonin, synthesis of, 271.Yonogenin, structure of, 323.Zeisel method, examination of, 448.Zinc, compounds of, 163.dtmn. of, 446.peroxide hydrates, 163.Zirconium tetrachloride, aminolysis of,trihalides, preparation of, 155.Zone melting, 423.154

ISSN:0365-6217    

DOI:10.1039/AR9605700545

出版商:RSC    

年代:1960

数据来源: RSC

摘要:

PRINCIPAL REFERENCES USED IN CHEMICAL SOCIETYPUBLICATIONS AS FROM JANUARY, 1960REFERENCE.Act. sci. ind. .Acta Acad. Aboensis, Math.Acta Biochim. Polon. .Acta Biochim. Sinica .Acta Biol. Acad. Sci. Hung.Acta Brev. Neer. Physiol. .Acta Chem. Phys. .Acta Chem. Scand. .Acta Chim. Acad. Sci. Hung.Acta Chim. Belg. .Acta Chim. Sinica .Acta Cryst.Acta Med. Scand:Acta Metallurgica .Acta Path. Microbiol. Scand.Acta Phys. Acad. Sci. Hung.Acta Phys. et Chem. Szeged.Acta Physicochim. U.R.S.S.Acta Physiol. Acad. Sci. Hung.Acla Phytochim., Tokyo .Acta Vitaminol. .Adv. Biol. Med. Plays.Adv. Carbohydrate Chem. .Adv. Catalysis .Adv. Chem. Eng. .Adv. Chem. Phys. .Adv. Clin. Chem.Adv. Colloid Sci..A dv . Enzy mol.Adv. Food Res. .Adv.Inorg. Chem. Radiochenz.Adv. Pest Control Res.Adv. Phys.Adv. Protein Chem. .Advancement Sci. .Ajinidad .Agra Univ. J . X i s . (Sci.)Agric. Chem. .Agrokdm. ks Talajtan .Ambix .Phys. .1Amer. Ceram. SOC. Bull. .Amer. Chem. J . .Amer. Dyestuff Reportel. .A mer. Inst. C h e w EngineevsAmer. Inst. M i n . Met. Engin-Amer. J . Bot. ,Amer. J . Digest. Dis. .Amer. J . Med. Sci. .Amer. J . Pharm. .Amer. J . Physiol. .Amer. J. Publ. Health .J . -eersFULL TITLE.Actualitks scientifiques et industrielles.Acta Academiae Aboensis, Mathematica et Physica.Acta Biochimica Polonica.Acta Biochimica Sinica.Acta Biologica Academiae Scientiarum Hungaricae.Acta Brevia Neerlandica de Physiologia, Pharmacologia,Acta Chemica et Physica.Acta Chemica Scandinavica.Acta Chimica Academiae Scientiarum Hungaricae.Acta Chimica Belgica.Acta Chimica Sinica.Acta Crystallographica.Acta Medica Scandinavica.Acta Metallurgica.Acta Pathologica et Microbiologica Scandinavica.Acta Physica Academiae Scientiarum Hungaricae.Acta Physica et Chemica.Acta Universitatis Szege-Acta Ph ysicochimica U. R.S. S.Acta Physiologica Academiae Scientiarum Hungaricae.Acta Phytochimica, Tokyo.Ac ta Vita mino lo gica .Advances in Biological and Medical Physics.Advances in Carbohydrate Chemistry.Advances in Catalysis.Advances in Chemical Engineering.Advances in Chemical Physics.Advances in Clinical Chemistry.Advances in Colloid Science.Advances in Enzymology.Advances in Food Research.Advances in Inorganic Chemistry and Radiochemistry.Advances in Pest Control Research.Advances in Physics.Advances in Protein Chemistry.Advancement of Science.Afinidad.Agra University Journal of Research.Agricultural Chemicals.Agrokkmia 6s Talajtan.Ambix.Journal of the Society for the Study of Alchemyand Early Chemistry.American Ceramic Society Bulletin.American Chemical Journal.American Dyestuff Reporter.American Institute of Chemical Engineers JournaI.American Institute of Mining and Metallurgical EngineersAmerican Journal of Botany.American Journal of Digestive Diseases.American Journal of Medical Sciences.American Journal of Pharmacy.American Journal of Physiology.American Journal of Public Health and the Nation’sMicrobiologia, e.a.diensis.Science.Publication.Health.55558 PRINCIPAL REFERENCES USED.REFERENCE.Amer.J . Roentgenol. .Amer. J . Sci. .Amer. Math. Soc., Coll. Publ.Amer. Min. .A mer. Perfumer A romatics .Anais Acad. brasil. Cienc. .Anais Assoc. brasil. Quim. .Anais Assoc. quim. e a s i l .Anal. $ti., Univ. Al. I .Anales Asoc. qztim. argentinaA nales Bromalol.Anales Fac. Farm. Bioqattm.,Univ. nac. mayor SanMarcosAnales real Soc. espaii. Fis.Quim. .A nalyst .Analyt. Chew .Analyt. Chim. Acta .Anat. Rec.Angew. Chem. .Ann. Acad. Sci. Fennicae .Cuza,” Iaji, Sect. IAnn. Biochem. Exp. Med.(India)Ann. Bot. .Ann. Chim. (France) .Ann. Chim. (Italy) .Ann. Chim. analyt. .Ann. Chim. appl.,Ann. Chim. Phys. .Ann. Endocrinol. .Ann. Fals. Fraudes .Ann. Ferment. .Ann. Iwt. Pasteur .Ann. Intern. Med. .Ann. Nutrition Aliment. .Ann. pharm. franF. .Ann. Physik .Ann. Physique .Ann. Report Fac. Plaarm.,Ann. Report ITSUU Lab. .Ann. Report Takamine Lab.Ann. Reports .Ann. Rev. Biochem. .Ann. Rev, Microbiol. .Ann. Rev. Nuclear Sci. .Ann. Rev. Phys. Chem. .Ann. Rev. Plant Physiol. .Ann. Sci. .Ann. Sect. Anal. phys. china.Ann. SOC. sci. Bruxelles .Ann. Sfler. agrar. .Ann. Stazione chim.-agrar.sper., RomaAnn. Univ. M. Cuuie-Sklo-dowskaAnn. Univ. Turkuensis, Ser.AAnnalen .Annuaire Acad. roy. Belg. .Kanazawa Univ.FULL TITLE.American Journal of Roentgenology and RadiumAmerican Journal of Science.American Mathematical Society, Collective Publications.American Mineralogist.American Perfumer and Aromatics.Anais da Academia brasileira de Ciencias.Anais da Associaqgo brasileira de Quimica.Anais da AssociacZo quimica do Brasil.Analele Stiintifice ale Universitgtii “Al.I. Cuza ” dinAnales de la Asociaci6n quimica argentina.Anales de Bromatologica.Anales de la Facultad de Farmacia y Bioquimica,Therapy.Iagi. Sectiurea I. Matematic& Fizicg, Chimie.Universidad nacional mayor de San Marcos.Anales de la real Sociedad espaiiola de Fisica y QuCmica.Analyst.Analytical Chemistry.Analytica Chimica Acta.Anatomical Record.Angewandte Chemie.Annales Academiae Scientiarium Fennicae (SuomalaisenAnnals of Biochemistry and Experimental Medicine.Annals of Botany.Annales de Chimie.Annali di Chimica.Annales de Chimie analytique et de Chimie appliqu6e.Annali di Chimica applicata.Annales de Chimie et de Physique (now divided: seeAnnales d’Endocrinologie.Annales des Falsifications et des Fraudes.Annales des Fermentations.Annales de 1’Institut Pasteur.Annals of Internal Medicine.Annales de la Nutrition et de I’ Alimentation.Annales pharmaceutiques frangaises.Annalen der Physik.Annales de Physique.Annual Report of the Faculty of Pharmacy.Annual Report of the ITSUU Laboratory.Annual Report of the Takamine Laboratory.Annual Reports on the Progress of Chemistry.Annual Review of Biochemistry.Annual Review of Microbiology.Annual Review of Nuclear Science.Annual Review of Physical Chemistry.Annual Review of Plant Physiology.Annals of Science.Annales du Secteur d’hnalyse physicochimique, InstitutAnnales de la SociCt6 scientifique de Bruxelles.Annali della Sperimentazione agraria.Annali della Stazione chimica-agraria sperimentale,Annales Universitatis Mariae Curie-Sklodowska (sarevulAnnales Universitatis Turkuensis.Series A. Astrono-Annalen der Chemie (Liebig’s).Annuaire hcademie royale de Belgique.Tiedeakatemian Toimit uksia) .Ann. Chim. and Ann. Phys.).KanazawaUniversity.de Chimie gCn6rale (U.R.S.S.).Roma.sections).mica, Chemica, Physica, MathematicaPRINCIPAL REFERENCES USED. 559REFERENCE.A ntibiotics and ChemotherapyAppita .Appl. Spectroscopy .Arch. Biochem. .Arch. Biochem.Biophys. .Arch. Eisenhiittenw. .Arch. exp. Path. Pkamzakol. .Arch. klirt. Chir.‘4 rch. Mikrobiol.Arch. Pharm. .Arch. Sci. .Arcla. Sci. biol. (U.R.S.S.) .Arch. Sci. phys. nnt. .A mh. 2001.Arhiv Kem. .Arkiv Fys.Arkiv Kemi .Arkiv Kemi, Min., Geil.Atomic World .Atomics .Atti Accad. naz. Lincei, Rend.Classe Sci..fis. mat. nat.A f t i R. Accad. Sci. Torino .Austral. J . Agvic. Res.Austral. J . Appl. Sci. .Ausiral. J . Riol. Sci. .Austral. J . Chem. .Austral. J . Exp. Biol. Med.Atcstml. J , Phys. .Avh. norske Vidensk.-Akad.Oslo, Afat.-nat. Kl.Apoth.-Ztg. .Sci.FULL TITLE.Antibiotics and Chemotherapy.Deutsche Apotheker-Zeitung.Appita.Applied Spectroscopy.Archives of Biochemistry.Archives of Biochemistry and Biophysics.Archiv fur das Eisenhuttenwesen.Archiv fur experimentelle Pathologie und Pharma-Archiv fur klinische Chirurgie.Archiv fur Mikrobiologie.Archiv der Pharmazie.Archives des Sciences.Archives des Sciences biologiques (U.R.S.S.) .Archives des Sciences physiques et naturelles.Archives d e Zoologie experimentale et gknkrale.Arhiv za Kemiju.Arkiv for Fysik.Arkiv for Kemi.Arlriv for Kemi, Mineralogi och Geologi.Atomic World.Atomics.Atti della Accademia nazionale dei Lincei, Rendicontidella Classe di Scienze fisiche, matematiche e naturali.Atti della Reale Accademia della Scienze di Torino.Australian Journal of Agricultural Research.Australian Journal of Applied Science.Australian Journal of Biological Sciences.Australian Journal of Chemistry.Australian Journal of Experimental Biology and MedicalAustralian Journal of Physics.Avhandlinger utgitt av det norske Videnskaps-AkademiJournal of the Australian Pulp and PaperIndustry.kologie.Science.i Oslo, Matema tisk-naturvidenskapelig Klasse.Batfele Tech.Rev. .Bcr. .Ber. deztt. bot. Ges. .Ber. deut. keratn. Ges. .Berg- u. hiitfe?cmdizn. Moit-atsh. wtontan. HochschuleLcobenBiochem. (U.S.S.R.) .Biochem. Biophys. Res. Conzm.Biochem. J . .Biochem. Pharmacol. .Biochem. SOC. Syinp. .Biochem. Z. .Biochina. .Biochim. appl. .Biochim. Biophys. A d a .Biofizika .Biokhimiya .Biol. Rev. Camb. Phil. SOC. .Bid. Zentr. .Bol. Inst. Quim. agrlc. (Brazil)Bol. Inst. Qulm. Univ. nac.Bol. Soc.chilena Qulm. .Bol. Soc. qulm. Peru .BolZ. chim. farm.auton. MbxicoBattele Technical Review.Berichte der deutschen chemischen Gesellschaft.Berichte der deutschen botanisclien Gesellschaft.Berichte der deutschen keramischen Gesellschaft.Berg- und huttenmannische Monatsliefte der montan-Biochemistry (U.S.S.R.). New York. U.S. translationBiochemical and Biophysical Research Communications.Biochemical Journal.Biochemical Pharmacology.Biochemical Society Symposia.Biochemische Zeitschrift.Biochimica.Biochimica applicata.Biochimica et Biophysica Acta.Biofizika.Biokhimiya. [See also Biochemistry (U.S.S.R.).]Biological Reviews of the Cambridge PhilosophicalBiologisches Zentralblatt.Boletim do Instituto de Quimica agricola.Boletin del Instituto de Quimica de la UniversidadBoletin de la Sociedad chilena de Quimica.Boletin de la Sociedad quimica del Peru.Bolletino chimico farmaceutico.(Changed to Chem.Ber. in 1946.)istichen Hochschule in Leoben.of Biokhimiya. DifjCerenl pagination.Society.nacional autonoma de Mexico560 PRINCIPAL REFERENCES USED.REFERENCE.Boll. sci. Fac. Chim. ind.BolognaBoll. SOC. ital. Biol. sper. .Bot. Gaz. .Botyu-Kagaku .Brennstofl-Chem. .Brit. Abs. .Brit. Bull. Spectroscopy .Brit. Chem. Eng. .Brit. Chemist .Brit. Dental J . .Brit. J . A@. Phys. .Brit. J . Exp. Path. .Brit. J . Ophthalmol. .Brit. J . Pharmacol. .Brit. J . Radiol. .Brit. J . Urol. .Brit. Med J . .Brit. Overseas Pharmacist .B u l . Inst.Politeh. Iasi ,Bull. Acad. polon. Sci., Ser.Bull. classe sci., Acad. roy.Bull. Acad. Sci. Roatmaine .Sci. chim., geol., geog.Belg.Bull. Acad. Sci. U.S.S.R. .Bull. Agric. Chem. SOG. JapanBull. Amer. Ceram. Soc. .Bull. Amer. Phys. Soc. .Bull. analyt. .Bull. Biol. Med. exp. U.R.S.S:Ball. Brit. Coal UtilisationBull. Brit. Soc. Rheol.Bull. Calcutta School Trop.Bull. Chem. Soc. Japan .Bull. Chim. SOC. Ronzdne .Res. Assoc.Med. .Bull. Classe Sci., Acad. roy.Bull. Exp. Biol. Med. .Bull. Hlth. Org. .Bull. Hyg.Bull. Imp. Inst. .Bull. Inst. Chem. Res., h’yotoUniv.Bull. Inst. Metal Finishing .Bull. Inst. M i n . Met. .Bull. Inst. Iyuclear Sci. “BorisBull. Inst. Phys. Chem. Res.,Bull. Johns Hopkins Hosp. .Bull.Kobayasi Inst. Phys.Bull. Narcotics .Bull. Res.. Council Israel .Bull. scz., Conseil Acad.Belg.KidrichTokyoRes. .R.P.F., YougoslavieFULL TITLE.Bollettino scientific0 della Facolt& di Chimica industrialeBolletino della SocietA italiana di Biologia sperimentale.Botanical Gazette.Botyu-Kagaku. (Scientific Insect Control.)Brennstoff -Chemie.British Abstracts.British Bulletin of Spectroscopy.British Chemical Engineering.British Chemist.British Dental Journal.British Journal of Applied Physics.British Journal of Experimental Pathology.British Journal of Ophthalmology.British Journal of Pharmacology and Chemotherapy.British Journal of Radiology.British Journal of Urology.British Medical Journal.British and Overseas Pharmacist.Buletinul Institutului Politehnic din Iasi.Bulletin de 1’AcadCmie polonaise des Sciences, SeriesSciences chimiques, geologiques, et geographiques.Bulletin de la Classe des Sciences, AcadCmie royale deBelgique.Bulletin de la Section scientifique de l’Acad6mieRoumaine.Bulletin of the Academy of Sciences of the U.S.S.R.New York.US. translation of Izvestiya AkademiiNauk S.S.S.R., Otdelenie khimicheskikh Nauk. Dif-ferent pagination.Bulletin of the Agricultural Chemical Society of Japan.Bulletin of the American Ceramic Society.Bulletin of the American Physical Society.Bulletin analytique.Bulletin de Biologie et Medicine experimentale deBulletin of the British Coal Utilisation Research Associa-Bulletin of the British Society of Rheology.Bulletin of the Calcutta School of Tropical Medicine.Bulletin of the Chemical Society of Japan.Bulletinul de Chimie pura si aplicata a1 SocietatiiBulletin de la Classe des Sciences, AcadCmie royale deBulletin of Experimental and Biological Medicine.Bulletin of the Health Organisation of the League ofBulletin of Hygiene.Bulletin of the Imperial Institute, London.Bulletin of the Institute for Chemical Research, KyotoBulletin of the Institute of Metal Finishing.Bulletin of the Institution of Mining and MetalluLgy.Bulletin of the Institute of Nuclear Sciences BorisBulletin of the Institute of Physical and ChemicalBulletin of the Johns Hopkins Hospital.Bulletin of the Kobayasi Institute of Physical Research.Bulletin on Narcotics.Bulletin of the Research Council of Israel.Bulletin scientifique, Conseil des AcadCmies de la R.P.F.,di Bologna.1’U.R.S.S.tion.Romane de Chimie.Belgiqu e.Nations.University.Kidrich. ”Research, Tokyo.YougoslaviePRINCIPAL REFERENCES USED. 561REFERENCE.Bull.SOC. chim. belges .Bull. SOC. chim. Beograd .Bull. SOC. Chim. biol. .Bull. SOC. chim. France .Bull. SOC. roy. Sci. Lit?ge .Bull. Soc. sci. Bretagne .Bur. Stand. J . lies. .FULL TITLE.Bulletin des SociCtCs chimiques belges.Bulletin de la SociCt6 chimique de Beograd.Bulletin de la SociCtC de Chimie biologique.Bulletin de la SociCtC chimique de France.Bulletin de la SociCtC royale des Sciences de Libge.Bulletin de la SociCtC scientifique de Bretagne.Bureau of Standards Journal of Research.Canad. Chem.Processing .Canad. J . Biochem. Physiol.Canad. J . Chem..Canad. J . Chem. Eng. .Canad. J . Phys. .Canad. 1. Res. .Canad. Med. Assoc. J . .Cellulosechem. .Cereal Chem. .Cesk. Farm. .Chem. Abs.Chem. Age .Chem. Analit. .Chem. Analyst .Chem. and Ind. .Chem. Bey.Chem. Eng. .Chem. Eng. (Japan) .Chem. Eng. News .Chem. Eng. Progv. .Chem. Eng. Progr., MonographChem. Eng. Progr., Symp. .Chem. Eng. Sci.Chem. Erde .Chem. Fabr. .Chem. High Polymers (Japan)Chem. in Canada .Chem. Ind. (Diisseldorf) .Chem.-Ing.-Tech. .Chem. Listy .Chem. Obzor .Chem. Process Eng. .Chem. Products .Chem. prumysi .Chem. Rev.Chem. SOC. Special Publ. 1Chem. Stosowana .Chem.Tech. (Berlin) .Chem. Trade J . .Chem. Week .Chem. WeekbladChem. Zentr. .Chern.-Ztg.Chem. Zvesti .Chemie .Chemist and Druggist .Chemist-Analyst .Chemistry. (Quart. ChineseChem. SOC., Formosa)Chim. analyt. .Chimia (Switz.) .Chimica e Industria .Chimie et Industrie .Chinese J . Phys.Ciencia .Clin. Chem.Clinica Chim. Ac‘taCanadian Chemical Processing.Canadian Journal of Biochemistry and Physiology.Canadian Journal of Chemistry.Canadian Journal of Chemical Engineering.Canadian Journal of Physics.Canadian Journal of Research.Canadian Medical Association Journal.Cellulosechemie.Cereal Chemistry.CeskoslovenskA Farmacie.Chemical Abstracts.Chemical Age.Chemia Analityczna. Warsaw.Chemist Analyst.Chemistry and Industry.Chemische Berichte.Chemical Engineering.Chemical Engineering.Japan.Chemical and Engineering News.Chemical Engineering Progress.Chemical Engineering Progress, Monographs.Chemical Engineering Progress, Symposia.Chemical Engineering Science.Chemie der Erde.Chemische Fabrik.Chemistry of High Polymers (Japan).Chemistry in Canada.Chemische Industrie.Chemie-Ingenieur-Technik.Chemick6 Listy.Chemicky Obzor.Chemical and Process Engineering.Chemical Products and the Chemical News.Chemicky prumysl.Chemical Reviews.Chemical Society Special Publications.Chemia StosowanaChemische Technik.Chemical Trade Journal.Chemical Week.Chemisch Weekblad.Chemisches Zentralblatt.Chemiker-Zeitung.ChemickC Zvesti, Slovenskii AcadCmia, Vied, Bratislava.Chemie.Chemist and Druggist.Chemist-Analyst.Chemistry. (Published quarterly by the ChineseChemical Society, Formosa.)Chimie analytique.Chimia.Chimica e 1’Industria.Milar,.Chimie et Industrie.Chinese Journal of Physics.Ciencia .Clinical Chemistry.Clinica Chimica Acta562 PRINCIPAL REFERENCES USED.REFERENCE.Cold Spring Harbor Symp. .Coll. Czech. Chem. Comm. .Colloid J . (U.S.S.R.) .Colonial Geol. Mineral Re-Colonial Plant A mimai pro‘-Combustion and Flame ,sources .ducts .Comm. Fac. Sci. Univ. AnkaraCompt. rend. .Compt. rend. Acad. bulg. Sci.Compt. rend. Acad. Sci.Compt. remd. Soc. Biol. .Cow@. vend. Trav. Lab.CarlsbergContrib. Boyce Thompson Inst.Contrib. Cienti$c., Univ.Buenos Aires, Ser.C, Qulnz.Corrosion .Croat. Chem. Acta .Current Sci. .U.R.S.S.Dansk Tidsskr. Farm.Dechema Monograph. .Deut. Lebensm.-Rundschau .Deut. med. Woch. .Discuss. Faraday Soc. .Diss. Abs. .Doklady Akad. Nauk S.S.S.R.Dopovidi A kad. Nauk,Ukrain. R. S. R.D.S.I.R. Publ. .E . African Med. J . .Edin. Med. J . .Egypt. J . Chem. .Electrochim. Acta .Elektrotech. 2. .EndeavourEngenharia e Qdmica .Enzymologia .Eng. Min. J . .Erdol u. Kohb .Ergebn. Enzymforsch. .Ergebn. exakt. Naturwiss. .Ergebn. Physiol. .Ergebn. Vitamin- u. Hormon-Ernahrungsforschung .Euclides .Experientia .forsch. .Fed. Proc.Fette u. Seifen .Finska KemistsamfundetsMedd.FULL TITLE.Cold Spring Harbor Symposium on QuantitativeCollection of Czechoslovak Chemical Communications.Colloid Journal (U.S.S.R.).New York. U.S. transla-Colonial Geology and Mineral Resources.Colonial Plant and Animal Products.Combustion and Flame. (Quarterly Journal of theCommunications de la FacultC des Sciences de 1’Uni-Comptes rendus hebdomadaires des SCances deComptes rendus de 1’AcadCmie bulgare des Sciences.Comptes rendus de l’hcadkmie des Sciences deU.R.S.S.Comptes rendus hebdomadaires des Skances de laSociktC de Biologie et des Filiales.Comptes rendus des Travaux du Laboratoire de Carls-berg.Contributions from the Boyce Thompson Institute.Contributions Cientificas, Universidad de Huenos Aires,Serie C, Quimica.Corrosion.Croatica Chemica Acta.Current Science.Biology.tion of Kolloidnyi Zhurnal.Digerent pagination.Combustion Institute.)versitC d’Ankara. B.1’AcadCmie des Sciences.Dansk Tidsskrift for Farmaci.Dechema Monographien.Deutsche Lebensmittel-Rundschau.Deutsche medizinische Wochenschrift.Discussions of the Faraday Society.Dissertation Abstracts. Ann Arbor, Mich. (AbstractsDoklady Akademii Nauk S.S.S.R. (See also ProceedingsDopovidi Akademii Nauk, Ukraiiis’koi Radians’koiD. S. I. R. Publications.of some U.S. theses, issued commercially.)of the Academy of Sciences of the U.S.S.R.)Sotsialistichnoi Respu’liki.East African Medical Journal.Edinburgh Medical Journal.Egyptian Journal of Chemistry.Electrochimica Acta.Elektrotechnische Zeitschrift.Endeavour.Engenharia e Qufmica.Enz ymologia.Engineering and Mining Journal.Erdol und Kohle.Ergebnisse der Enzymforschung.Ergebnisse der exakte Naturwissenschaften.Ergebnisse der Physiologie.Ergebnisse der Vitamin- and Hormonforschung.Ernahrungsforschung.Euclides.Experientia.Federation Proceedings.Fette und Seifen einschliesslich der Anstrichmittel.Finska Kemistsamfundets Meddelanden (Suomen Kemi-stiseuran Tiedonantoja) PRINCIPAL REFERENCES USED.563REFERENCE.Fiz. Metall. i Metallov. .FoodFood M a n i f .Food Res. .Food Technol. .Forschungsber. Wirtschafts- u.VerkehrsministeriumsNordrhein- WestfaZenFortschr. chem. Forsch.Fortschr. Chem. org. NaturstofleFortschr. Hochpolyrn .-Forsch.FuelGazzetta .Geneesk. Tijdschr. Neder1.-Indie .General Cytochem. Methods .Gknie chim, .Geochemistry (U.S.S.R.) .Geochim.Cosmochim. Acta .Geokhimiya .Geol. Mag.Gidrokhim. Mat.Giorn. Biochim. .Grasas y Aceites .Helv. Chim. Acta .Hetv. Phys. Acta .Helv. Physiol. Pharmacol. ActaInd. Chemist Chem. Manuf.Ind. Chemist .Ind. chim. .Ind. chim. belgeInd. Eng. Chem.Ind. Eng. Chem., Analyt. .Ind. Eng. Chem., Chem. Eng.Ind. Finishing .Ind. ParfumerieIndian J . Appl. Chem. .Indian J . Med. Res. .Indian J . Pharm. .Indian J . Phys.Indian Pharmacist .Industria y Quimica .Ing.-chim. .Inorg. Synth. .Inst. Hierro Acero .Inst. internat. China. SolvayConseil Chim.Tnst. Petroleum Rev. .Internat. J . Appl. RadiationIsotopesInternat. J . Radiation Biol.Internat.2. Vitaminforsch. .Iowa State Coll. J . Sci. .Izvest. Akad. Nauk Armian.S.S.R. khim. Nauk.Izvest. Akad. Nauk S.S.S.R.,Otdel. khim. NaukData Ser.FULL TITLE.Fizika Metallov i Metallovdenie.Food.Food Manufacture.Food Research.Food Technology.Forschungsberichte des Wirtschafts- und Verkehrsmini-steriums Nordrhein-Westfalen.Fortschritte der chemischen Forschung.Fortschritte der Chemie organischer Naturstoffe.Fortschritte der Hochpolymeren-Forschung.Fuel.Gazzetta chimica italiana.Geneeskundig Tijdschrift voor Nederlandsch-Indie.General Cytochemical Methods.Genie chimique (suppl. to Chimie et Industrie).Geochemistry (U.S.S.R.). New York.Geochimica et Cosmochimica Acta.Geokhimiya. [See also Geochemistry (U.S.S.R.).]Geological Magazine.Gidrokhimicheskie Materialy.Giornale di Biochimica.Glasnik Khemiskog Drushtra Beograd.chim. Beograd.)Grasas y Aceites.Helvetica Chimica Acta.Helvetica Physica Acta.Helvetica Physiologica et Pharmacologica Acta.Industrial Chemist and Chemical Manufacturer.Industrial Chemist.Industrie chimique et le phosphate r6unis.Industrie chimique belge.Industrial and Engineering Chemistry.Industrial and Engineering Chemistry: AnalyticalEdition.Industrial and Engineering Chemistry, Chemical andEngineering Data Series.Industrial Finishing.Industries de la Parfumerie.Indian Journal of Applied Chemistry.Indian Journal of Medical Research.Indian Journal of Pharmacy.Indian Journal of Physics.Indian Pharmacist.Industria y Quimica.Inghieur-chimiste.Inorganic Syntheses.Instituto de Hierro y del Acero.Institut international de Chimie Solvay Conseil deInstitute of Petroleum Review.International Journal of Applied Radiation and Isotopes.International Journal of Radiation Biology.Internationale Zeitschrift fur Vitaminforschung.Iowa State College Journal of Science.Izvestiya Akademii Nauk Armianskoi S.S.R.khimi-cheskie Nauki.Izvestiya Akademii Nauk S.S.S.R., Otdelenie khimiche-skikh Nauk. Moscow. (See also Bulletin of theAcademy of Sciences of the U.S.S.R.)(Quarterly Journal of Fuel Science.)U.S. translationof Geokhimiya. Different pagination.(See Bull. SOC.Chimie 564 PRINCIPAL REFERENCES USED.REFERENCE.Imest. Sekt. $2.-khim. Anal.,Insf.obshchei neorg. Khim.lavest. Sekt. Platiny drug. bla-gorod. Metal., Inst. obshcheineorg. Khim.J -J . Agric. Chem. Soc. Japan .J . Agric. Food Chem. .J . Agric. Res. .J . Agric. Sci. .J . Amer. Ceram. SOC. .J . Amev. Chem. SOC. .J . Amer. Leather Chemists’J . Amer. Med. Assoc. .J . Amer. Oil Chemists’ SOC. .J . A mer. Pharmaceut. Assoc.J . Analyt. Chem. (U.S.S.R.).Assoc. .(Sci. Edn.)J . Appl. Chem. .J . Appl. Chem. (U.S.S.R.)J . Appl. Phys.J . Appl. Phys. (U.S.S.R.)J . Appl. Polymer Sci.J . Assoc. O@c. Agric. ChemistsJ . Bact. .J . Biochem. (Japan) .J . Biochem. Microbiol. Tech-nol. Eng. .J . Biol. Chem. .J . Biol. Chem., Sci. Proc. .J . Cell. Comp. Physiol. .J . Chem. Educ. .J . Chem., Met., Mining Soc.J .Chem. Phys. .J . Chem. SOC. Japan .J . Chem. SOC. Japan, Ind.Chem. Sect.J . Chim. phys. .J . Chinese Chem. SOC. (For-J . Chromatog. .J . Clan. Invest. .J . Colloid Sci. .J . Cozcncil Sci. Ind. Res.,S. Africamosa)AustraliaEcon. Entomol. .Electrochem. SOC. .Electrochem. SOC. Japan .Endocrinol. .Exp. Biol. .Exp. Med. .Fac. Sci. Univ., Tokyo .Franklin Inst. .FULL TITLE.Izvestiya Sektora fiziko-khimicheskogo Analiza, Institutobshchei i neorganicheskoi Khimii, Akademii NaukS.S.S.R.Izvestiya Sektora Platiny i drugikh blagorodnykhMetallov, Institut obshchei i neorganicheskoi Khimii,Akademii Nauk S.S.S.R.Journal of the Chemical Society.Journal of the Agricultural Chemical Society ofJournal of Agricultural and Food Chemistry.Journal of Agricultural Research.Journal of Agricultural Science.Journal of the American Ceramic Society.Journal of the American Chemical Society.Journal of the American Leather Chemists’ Association.Journal of the American Medical Association.Journal of the American Oil Chemists’ Society.Journal of the American Pharmaceutical Association(Sci. Edn.).Journal of Analytical Chemistry (U.S.S.R.).New York.U.S. translation of Zhurnal analiticheskoi Khimii.Different pagination.Journal of Applied Chemistry (London).Journal of Applied Chemistry (U.S.S.R.). New York.U S . translation of Zhurnal prikladnoi Khimii. Dif-ferent pagination.Journal of Applied Physics.Journal of Applied Physics (U.S.S.R.).Journal of Applied Polymer Science.Journal of the Association of Official AgriculturalJournal of Bacteriology.Journal of Biochemistry (Japan).Journal of Biochemical and Microbiological TechnologyJournal of Biological Chemistry.Scientific Proceedings of the American Society ofJournal of Cellular and Comparative Physiology.Journal of Chemical Education.Journal of the Chemical, Metallurgical and MiningSociety of South Africa.Journal of Chemical Physics.Journal of the Chemical Society of Japan.Journal of the Chemical Society of Japan, IndustrialJournal de Chimie physique.Journal of the Chinese Chemical Society (Formosa).Journal of Chromatography.Journal of Clinical Investigation.Journal of Colloid Science.Journal of the Council for Scientific and IndustrialJournal of Economic Entomology.Journal of the Electrochemical Society.Journal of the Electrochemical Society of Japan.Journal of Endocrinology.Journal of Experimental Biology.Journal of Experimental Medicine.Journal of the Faculty of Science (Imperial) University,Journal of the Franklin Institute.Japan.Chemists.and Engineering.Biological Chemists (bound with J .Biol. Chem.).Chemistry Section.Research, Australia.TokyoPRINCIPAL REFERENCES USED. 565REFERENCE.J . Gen. Chem. (U.S.S.R.) .J . Gen. Physiol. .J . Geol. .J . Histochem. Cytochem. .J . Immunol. .J . Imp. Coll. Chem. Eng. SOC.J . Ind. Eng. Chem. .J . Ind. Hyg. .J . Indian Chem. SOC. .J . Indian Chem. Soc., Ind.J . Indian Inst. Sci. .J .Infect. Dis. .J . Inorg. Nuclear Chem. .J . Inst. Brewing. .J . Inst. Elect. Engineers .J . Inst. Fuel .J . Inst. Metals .J . Inst. Petroleum .J . Inst. Polytechnics, OsakaJ . Internat. Soc. LeatherJ . Iron Steel Inst. .J . Karnatak Univ. .J . Lab. Clin. Med. .J . Less Common Metals .J , Lipid Res. .J . Madras Univ.J . Marine Biol. Assoc.J . Marine Res. .J . Medicin. Pharmaceut. Chem.J . Mol. Biol. .J . Mol. Spectroscopy .J . New Zealand Inst. Chem.J . Neurochem. .J . Nuclear Materials .J . Nutrit. .J . Ozl Colour Chemists’ Assoc.J . Opt. SOC. Amer. .J . Org. Chew. .J . Osaka Inst. Sci. Technol.(Kinki Univ.)J . HYg- -News Edn.City Univ.ChemistsPediat. .Pharm. Belg. .Pharm. Chim.Phavm. Pharmacol.Pharm. SOC.Japan .Pharmacol. .Phot. Sci. .Phys. and Chem. Soiids :Phys. Chem.Phys. Colloid Chem.’Phys. Radium .Phys. Soc. Japan .Phys. (U.S.SJ2.j .Physiol. .Polarog. SOC. .Polymer Sci. .prakt. Chem. .FULL TITLE.Journal of General Chemistry (U.S.S.R.).U S , translation of Zhurnal obshchei Khimii.ferent pagination.Journal of General Physiology.Journal of Geology.Journal of Histochemistry and Cytochemistry.Journal of Hygiene.Journal of Immunology.Journal of the Imperial College Chemical EngineeringJournal of Industrial and Engineering Chemistry.Journal of Industrial Hygiene and Toxicology.Journal of the Indian Chemical Society.Journal of the Indian Chemical Society, Industrial andJournal of the Indian Institute of Science.Journal of Infectious Diseases.Journal of Inorganic and Nuclear Chemistry.Journal of the Institute of Brewing.Journal of the Institution of Electrical Engineers.Journal of the Institute of Fuel.Journal of the Institute of Metals.Journal of the Institute of Petroleum.Journal of the Institute of Polytechnics, Osaka CityJournal of the International Society of Leather TradesJournal of the Iron and Steel Institute.Journal of the Karnatak University.Journal of Laboratory and Clinical Medicine.Journal of the Less Common Metals.Journal of Lipid Research.Journal of Madras University.Journal of the Marine Biological Association of theJournal of Marine Research.Journal of Medicinal and Pharmaceutical Chemistry.Journal of Molecular Biology.Journal of Molecular Spectroscopy.Journal of the New Zealand Institute of Chemistry.Journal of Neurochemistry.Journal of Nuclear Materials.Journal of Nutrition.Journal of the Oil and Colour Chemists’ Association.Journal of the Optical Society of America.Journal of Organic Chemistry.Journal of the Osaka Institute of Sciences and Tech-nology (Kinki University).Journal of Pediatrics.Journal de Pharmacie de Belgique.Journal de Pharmacie et de Chimie.Journal of Pharmacy and Pharmacology.Journal of the Pharmaceutical Society of Japan.Journal of Pharmacology and Experimental Thera-Journal of Photographic Science.Journal of Physics and Chemistry of Solids.Journal of Physical Chemistry.Journal of Physical and Colloidal Chemistry.Journal de Physique et le Radium.Journal of the Physical Society of Japan.Journal of Physics (U.S.S.R.)Journal of Physiology.Journal of the Polarographic Society.Journal of Polymer Science.Journal fur praktisclie Chemie.New York.Dif-Society.News Edition.University.Chemists.U.K.peutics566 PRINCIPAL REFERENCES USED.REFERENCE.J.Proc. Austral. Chem. Inst.J . Proc. Inst. Chemists (India)J . Proc. Inst. Sewage Purif.J . Proc. Roy. SOC. New SouthJ . Ramsay SOC. Chem. En-J . Res. Iast. Catalysis, Hok-J . Res. Nat. Bur. Stand. .J . Roy. Inst. Chem. .J . Roy. Microscop. SOC. .J . Roy. SOC. Arts .J . Rubber Res. .J . Russ. Phys. Chem. SOC. .J . S. African Chem. Inst. .J . S. African Inst. MiningJ .Sci. Food Agric. .J . Sci. Hiroshima Univ. .J . Sci. Ind. Res., India .J . Sci. Instr. .f. Sci. Res. Inst., Tokyo .J . SOC. Chem. Ind. .J . SOC. Chem. Ind., Japan .J . SOC. Cosmetic Chemists .J . SOC. Dyers and Colourists .J . SOC. Glass Technol.J . SOC. Leather Trades.’Chemists. .J . Textile Inst. .J . Washington Acad. Sci. .Jap. J , Exp. Med. .Jap. J . Med. Sci. Biol. .Jap. J . Pharmacol. .Japan Analyst .K. ned. SpringstoffenfabriekenKgl. danske Videnskab. Sels-kab, Mat.-fys. Medd.Kgl. danske Videnskab. Sels-kab, Mat.-fys. SkrifterKgl. fysiogr. Sallsk. LundForh. .Kgl. norske Videnskab. Sels-kabs Forh. .Kgl. norske Videnskab. Sels-kabs SkrifterKgl. svenska Vetenskapsakad.H a n d .Khim. i I n i .Khint.Prom. .Kolloid-Beih. .Kolloid 2. .Kolloid. Zhur. .KristallogvajiyaKumarnoto Pharin. Bull. .Walesgzneers. .kaido Univ.Met.Lab. Practice .Lancet .FULL TITLE.Journal and Proceedings of the Australian ChemicalJournal and Proceedings of the Institution of ChemistsJournal and Proceedings of the Institute of SewageJournal and Proceedings of the Royal Society of NewJournal of the Ramsay Society of Chemical Engineers.Journal of the Research Institute for Catalysis, Hok-Journal of Research of the National Bureau of Standards.Journal of the Royal Institute of Chemistry.Journal of the Royal Microscopical Society.Journal of the Royal Society of Arts.Journal of Rubber Research.Journal of the Russian Physical and Chemical Society.Journal of the South African Chemical Institute.Journal of the South African Institute of Mining andJournal of the Science of Food and Agriculture.Journal of Science of the Hiroshima University.Journal of Scientific and Industrial Research, IndiaJournal of Scientific Instruments.Journal of the Scientific Research Institute, Tokyo.Journal of the Society of Chemical Industry.Journal of the Society of Chemical Industry, Japan.Journal of the Society of Cosmetic Chemists.Journal of the Society of Dyers and Colourists.Journal of the Society of Glass Technology.Journal of the Society of Leather Trades’ Chemists.Journal of the Textile Institute.Journal of the Washington Academy of Sciences.Japanese Journal of Experimental Medicine.Japanese Journal of Medical Science and Biology.Japanese Journal of Pharmacology.Japan Analyst.Koninklij ke nederlandsche Springstoff enfabrieken.Amsterdam.Kongelige danske Videnskabernes Selskab, Matematisk-fysiske Meddelelser.Kongelige danske Videnskabernes Selskab, Matematisk-fysiske Skrifter.Kongliga fysiografiska Sallskapets i Lund Forhandlinger.Kongelige Norske Videnskaber Selskabs Forhandlinger.Kongelige Norske Videnskaber Selskabs Skrifter.Kungliga svenska Vetenskapsakademiens Handlingar.Khimiia i Industria, Bulgariia.Khimicheskaya Promyshlennost’.Kolloid-Beihefte.Kolloid Zeitschrift.Kolloidnyi Zhurnal.[See also Colloid Journal (U.S.S.R.) .]Kristallografiya. [See also Soviet Physics Crysta-Kumamoto Pharmaceutical Bulletin.Laboratory Practice.Lancet.Liebig’s Annalen der Chemie.Institute.(India).Purification.South Wales.kaido University.MetalIurgy .graphy.1See AnnalenPRINCIPAL REFERENCES USED.567REFERENCE.Mag. Concrete Res. .Magyar Kbm. Folydirat .Magyar Ke'm. Lapja .Makromol. Chem. .Manuf. Chemist .Mededel. vlanm. chem. Ver. .Melliand Textilber. .Mem. Coll. Sci., Kyoto Univ.Mem. Fac. Ind. Arts, KyotoTech. Univ., Sci. and Tech.Mem. Fac. Sci., Kyushu Univ.Mem. Inst. Chem., Ukrain.Acad. Sci.Mem. Inst. Protein Res.,Osaka Univ.Mem, Inst. Sci. I d . Res.,Osaka Univ.Me'm. Poudres .Mew. Proc. Manchester Lit.Me'm. Services chim. €?tat .Metal Ind.Metallforsch. .Metallurgia .Methods Biochem. Analysis .Microchem. J ..Mie Med. J . .Metallw. .Mikrochem. .Mikrochem. Mikrochim. ActaMikrochim. Acta .Mineralog. Mag.Mitt. deut. pharm. Ges. .Mol. Phys. .Monatsh. .Phil. Soc.Nachr. Akad. Wiss. Gottingen,Nature .Naturwiss.Nederl. Tijds. Natuurk. .Neues Jahrb. Min. .New England J . Med.New Phytol. .New Zealand J . Sci. Technol.Nord. med. Tidsskr. .NucleonicsMath.-phys. IU.FULL TITLE.Magazine of Concrete Research.Magyar KCmiai Foly6irat.Magyar Kemikusok Lapja.Makromolekulare Chemie.Manufacturing Chemist.Mededelingen van de vlaamse chemische Vereniging.Melliand Textilberichte.Memoirs of the College of Science, Kyoto University.Memoirs. Faculty of Industrial Arts, Kyoto TechnicalMemoirs of the Faculty of Science, Kyushu University.Memoirs of the Institute of Chemistry, UkrainianMemoirs of the Institute for Protein Research, OsakaMemoirs of the Institute of Scientific and IndustrialM6morial des Poudres.Memoirs and Proceedings of the Manchester Literary andMemorial des Services chimiques de l'gtat.Metal Industry.Metallforschung.Metallurgia. British Journal of Metals.Methods of Biochemical Analysis.Microchemical Journal.Mie Medical Journal.Metallwirtschaft, Metallwissenschaft, Metalltechnik.Mikrochemie.Mikrochemie vereinigt mit Mikrochimica Acta.M ikroch imica Ac ta .Mineralogical Magazine and Journal of the MineralogicalMitteilungen der deutschen pharmazeutischen Gesell-Molecular Physics.Monatshefte fur Chemie und venvandte Teile andererWissenschaften.University, Science and Technology.Academy of Sciences.University.Research, Osaka University.Philosophical Society.Society.schaft.(Bound with Archiv der Pharmazie.)Nachrichten der Akademie der Wissenschaften in Got-Nature.Naturwissenschaften.Nederlandsch Tijdschrift voor Natuurkunde.Neues Jahrbuch fur Mineralogie, Kristallographie undPetrographie.New England Journal of Medicine.New Phytologist.New Zealand Journal of Science and Technology.Nordisk medicinisk Tidsskrift.Nucleonics.tingen, Mathematisch-physikalische Klasse.Nuovo cim. . Nuovo cimento.Nutrit. Abs. Rev. . Nutrition Abstracts and Reviews.osterr. Chem.-Ztg. . . Osterreichische Chemiker-Zeitung.Optics and Spectroscopy . Optics and Spectroscopy.U.S. translation of Optika iOrg. Reactions . . Organic Reactions.Org. Synth. . . Organic Syntheses.Spektroskopiya. Different pagination.Paint Manuf. . Paint Manufacture, incorporating Paint.Paint Oil Chem. Rev. . Paint, Oil and Chemical Review.Paint Technol. . , Paint Technology, incorporating Synthetic and AppliedPakistan J . Sci. Ind. Res. Pakistan Journal of Scientific and Industrial Research.Finishes.568 PRINCIPAL REFERENCES USED.REFERENCE.Pakistan J . Sci. Res. .Parfumerie u. Kosmetik ,Parfumerie, Cosmdt., SavonPerfumery Essent. Oil RecordPeriod& Polytech. .Pflug. Arch. ges. Physiol.Pharm. Acta Helv. .Pharm. Bull. (Japan) .Pharm. J .Pharm. Weekblad .Pharm. Zentralhalle .Pharm. Ztg. .PharmaziePhil. Mag..Phil. Trans. .Phys. and Chem. EarthPhys. Fluids .Phys. Rev.Phys. 2. .Phys. Z. Sovietunion .Physica .Physiol. Rev. .Plant Physiol. .Pogg. Ann. .Polarog. Ber.Post Grad. Med. ‘T.Poultry sci. .Prdce, Acta Acad. Sci. Cech.Prakt. Chemie .Pvoc. Acad. Nat. Sci. .Basis BrunensisProc. Acad. Sci. (U.S.S.R.)Proc. Amer. Acad. Arts Sci.Proc. Amer. SOC. BrewingProc. Cambridge Phil. SOC. .Proc. Chem. SOC.Proc. Geol. Assoc. .Proc. Imp. Acad. (Tokyo) .Proc. Indian Acad. Sci. .Proc. Indiana Acad. Sci. .Proc. Japan Acad. .Proc. k . ned. Akad. Weten-Proc. London Math. SOC. .Proc. Mayo Clin. .Proc. Nut. Acad. Sci. IndiaProc. Nut. Acad. Sci. U.S.A.Chemistsschap.Proc. Nut. Inst. Sci. India .Proc. Phys. SOC.Proc.Plastics Polymer Group,SOC. Chem. Ind.Proc. Roy. Irish Acad. .Proc. Roy. SOC. .Proc. Roy. Soc. Edinburgh .Proc. Roy. SOG. Medicine .Proc. Soc. Exp. Biol. Med. .Proc. Soil Sci. SOC. Amev. .FULL TITLE.Pakistan Journal of Scientific Research.Parfumerie und Kosmetik.Parfumerie, CosmCtique, Savon.Perfumery and Essential Oil Record.Periodica Polytechnica.Pfliigers Archiv fur die gesamte Physiologie desPharmaceutica Acta Helvetiae.Pharmaceutical Bulletin. Japan.Pharmaceutical Journal.Pharmaceutisch Weekblad.Pharmazeutische Zentralhalle fur Deutschland.Pharmazeutische Zeitung.Pharmazie.Philosophical Magazine.Philosophical Transactions of the Royal Society.Physics and Chemistry of the Earth.Physics of Fluids.Physical Review.Physikalische Zeitschrift.Physikalische Zeitschrift de.r Sowjetunion.Physica.Physiological Reviews.Plant Physiology.Poggendorf’s Annalen.Polarographische Berichte.Post Graduate Medical Journal.Poultry Science.PrAce, Acta Academiae Scientarum CechoslovenicaePraktische Chemie.Vienna.Proceedings of the Academy of Natural Sciences ofPhiladelphia.Proceedings of the Academy of Sciences of the U.S.S.R.New York. U.S. translation of Doklady AkademiiNau k S. S. S. R. Different pagination.Proceedings of the American Academy of Arts andSciences.Proceedings of the American Society of BrewingChemists.Proceedings of the Cambridge Philosophical Society.Proceedings of the Chemical Society.Proceedings of the Geologists’ Association.Proceedings of the Imperial Academy (Tokyo).Proceedings of the Indian Academy of Sciences.Proceedings of the Indiana Academy of Science.Proceedings of the Japan Academy.Proceedings, koninklij ke nederlandsche Akademie vanProceedings of the London Mathematical Society.Proceedings of the Staff Meetings of the Mayo Clinic.Proceedings of the National Academy of Sciences India.Proceedings of the National Academy of Sciences of theProceedings of the National Institute of Science ofProceedings of the Physical Society of London.Proceedings of the Plastics and Polymer Group, SocietyProceedings of the Royal Irish Academy.Proceedings of the Royal Society.Proceedings of the Royal Society of Edinburgh.Proceedings of the Royal Society of Medicine.Proceedings of the Society for Experimental Biology andProceedings of the Soil Science Society of America.Menschen und der Tiere.Basis Brunensis.Wetenschappen.United States of America.India.of Chemical Industry.MedicinePRINCIPAL REFERENCES USED.560REFERENCE.Progr. Biophysics Biophys.Progr. Chem. Fats and OtherProgr. Org. Chem. .Progr. Stereochew. .Przemysl Chem. .Publ. Amer. Assoc. Adv. Sci.Chem. .Lipids .FULL TITLE.Pzcbl. CERCHAR .Publ. I y t . Quim. “ AlonsoBarba .Quart. J . Exp. Physiol. .Quart. J . Geol. SOC. .Quart. J . Pharm. .Quart. Rev.Quimica e Industria .Radiation Res. .RadiologyRec. Trav. chim.Becent Progr. Hormone Res.Rec herc hesReport Brit. Assoc. .Report Sci. Res. Inst. (Japan)dieports Govt.Chem. I n d . Res.Reports Inst. Phys. Chem.Reports “ J . Stefan ” Inst. .Reports Progr. Phys. .Research .Rev. Asoc. bioquim. argentinaBev. brasil. Chim. .Rev. Chim. (Acad. R.P.R.) .Rev. Chim. (Roumawia) .Rev. Cienc. apl. .Rev. Fac. Cienc. quim., Univ.nac. L a PlataRev. Fac. Farm. Bioquim.,Univ. nac. mayor S a nMarcosRev. Fac. Qatim., Univ. nac.mayor S a n MarcosRev. Fac. Sci. Istanbul .Inst., TokyoRes. (Japan)Rev. Immunol. ,Rev. I n d . min. .Rev. Inst. frang. Pktrole ,Rev. Mod. Phys.Rev. Phys. Chem., J a p a n .Rev. Prod. chim.Rev. Pure Appl. Chem. (Aus-tralia)Rev. Quim. industrial .Rev. Quim. pura apI. ,Rev. sci. .Rev. Sci. Instr. .Ricerca sci.Riechstofle u. Aromen .Progress in Biophysics and Biophysical Chemistry.Progress in the Chemistry of Fats and Other Lipids.Progress in Organic Chemistry.Progress in Stereochemistry.Przemysl Chemiczny.Publications of the American Association for theAdvancement of Science.Publications CERCHAR (Centre d’gtudes et Recherchesdes Charbonnages de France).Publicaciones del Instituto de Quimica “ Alonso Barba.”Quarterly Journal of Experimental Physiology.Quarterly Journal of the Geological Society of London.Qiiarterly Journal of Pharmacy and Pharmacology.Quarterly Reviews.Quimica e Industria.Radiation Research.Radiology.Recueil des Travaux chimiques des Pays-Bas et de laBelgique.Recent Progress in Hormone Research.Recherches:Report of the British Association for the Advancementof Science.Report of the Scientific Research Institute (Japan).Reports of the Government Chemical Industrial Re-search Institute, Tokyo.Reports of the Institute of Physicaland Chemical ResearchReports J.Stefan ” Institute.Reports on Progress in Physics.Research.Revista de la Asociacih bioqufmica argentina.Revista brasileira de Chimica.Revue de Chimie (Acadkmie de la Rkpublique PopulaireRevista de Chimie (Roumania).Revista de Ciencia aplicada.Revista de la Facultad de Ciencias quimicas (Quimica yRevista de la Facultad de Farmacia y Bioquimica,Revista de la Facultad de Qufmica, Universidad nacionalRevue de la FacultC des Sciences de l’Universit6 d’Istan-Revue d’Immunologie.Revue de Z’Industrie minerale.Revue de 1’Institut franqais du P6trole et Annales desCombustibles liquides.Reviews of Modern Physics.Review of Physical Chemistry, Japan,Revue des Produits chimiques.Reviews of Pure and Applied Chemistry (Royal Aus-tralian Chemical Institute).Revista de Quimica industrial.Revista de Quimica pura 6 aplicada.Revue scientifique, Paris.Review of Scientific Instruments.Ricerca scientifica.Riechstoffe und Aromen.(Japan);Roumaine.)Farmacia).Universidad nacional mayor de San Marcos.mayor de San Marcos.bul.Universidad nacional de La Plata570 PRINCIPAL REFERENCES USED.REFERENCE.Roczniki Chenz..Roy. Inst. Chem. Lectures,Rubber Chem. Technol.Russ. Chem. Rev. . .Monographs, RepoitsRuss. J . Inorg. Chem. .Russ. J . Phys. Chem.. .S. African Ind. Chemist .S. African J . Sci. .Schweiz. Apoth.-Ztg. .Schweiz. med. Woch. .Sci. J . Roy. Coll. Sci. .Sci. Light .Sci. Papers Coll. Gen. Educ.,Sci. Papers Inst. Phys. Chem.Sci. Proc. Royal Dublin SOLSci. Progr.Sci. Reports Res. Inst., TGhokuUniv.Sci. Reports Saitama Univ. .Sci. Reports Soc. Res. Theor.Sci. Reports TBhoku Univ. .Sci. Sinica .Sci. Tools .Science .Science and Culture .Sitzungsber. Akad. Wiss.WienSitzungsber. (2s. Beford.ges. Naturwiss. MarburgSitzungsber. listerr. Akad.Wiss., Abt. I I BSkand. Arch. Physiol.Smithson. Misc. Coll. .Smokeless Air .Soap .Soc. Sci. Fennica, Cortinrenta-Soil Sci. ,Soviet Phys. Crystallog. .Spectrochim. Acfa .Sperimentale .Sperimentale, Sez.Cliiiiz. biol.Sta'rke .Stain Technol. .Sth. Med. J . .Studii si Cercetavi Chim.(Acad. R.P.R.)Studii si Cercetari Chim. (FiE.Studii si Cercetari Sti., Chim.(Baza Cercetari Sti., Timi-soara)Univ. TokyoRes. TokyoChem .tiones Phys.-Math.Cluj)FULL TITLE.Roczniki Chemji.Royal Institute of Chemistry, Lectures, Monographs, andReports.Rubber Chemistry and Technology.Russian Chemical Reviews (British translation ofUspeklii Khimii. Diflerent fiagwaalion.)Russian Journal of Inorganic Chemistry. (British trans-lation of Zhurnal neorganicheskoi Khimii. Differentpagination.)Russian Journal of Physical Chemistry. (British trans-lation of Zhurnal fizicheskoi Khimii. Di fferenl pagin-ation.)South African Industrial Chemist.South African Journal of Science.Schweizerische Apotheker-Zeitung.Schweizerische medizinische Wochenschrift.Scientific Journal of the Royal College of Science.Science of Light.(Institute of Optical Research.Scientific Papers of the College of General Education ,Scientific Papers of the Institute of Physical andScientific Proceedings of the Royal Dublin Society.Science Progress.Science Reports of the Research Institute, TbhokuUniversity.Science Reports of the Saitama University.Science Reports of the Society for the Research ofTheoretical Chemistry.Science Reports of the T6hoku University.Scientia Sinica.Science Tools.Science.Science and Culture.Sitzungsberichte der Akademie der Wissenschaften inSitzungsberichte der Gesellschaft zur BeforderungSitzungsberichte der osterreichische Akademie derSkandinavisches Archiv fur Physiologie.Smithsonian Miscellaneous Collection.Smokeless Air.Soap and Chemical Specialties.Societas Scientiorum Fennica, Commentationes Physico-Soil Science.Soviet Physics.Crystallography. U.S. translation ofSpectrochimica Acta.Sperimentale, Archivo di Biologica normale et Patologica.Sperimentale, Archivo di Biologica normale et Patologica,Starke.Stain Technology.Southern Medical Journal.Studii si Cercetari de Chimie. (Acadernie RepubliciiPopulare Romine.)Studii si Cercetari de Chimie. (Academia RepubliciiPopulare Romine. Filiala Cluj .)Studii si Cercetari Stiintifice Chimie. (Baza de CercetarjStiintifice, Timisoara.)Tokyo.)University of Tokyo.Chemical Research, Tokyo.Wien.der gesamten Naturwissenschaften zu Marburg.Wissenschaften, Abteilung IIB.Mathematicae.Kristallografiya.Diflerent pagination.Sezione di Chimica biologicaPRINCIPAL REFERENCES USED. 57 IFULL TITLE. REFERENCE.Studii s i Cercetari Sti. Chim.Studii s i Cercetari Sti., Ser. ISiiddeut. Apoth,-Ztg. ..%omen Kern. .Svensk kem. Tidskr. .Svensk Papperstidn. ,Symp. SOC. Exp. Biol.(Fil. Iasi)Talanta .Technol.Re$oyts TGhokzG Univ.Technol. Reports Osaka Univ.Tetrahedron .Tetrahedron Letters .Textile Res. J . .Tidsskr. Kjemi Bergvesen Met.Trans. Amer. SOC. Metals .Trans. Brit. Ceranz. SOC. .Trans. Chalmers Univ. Tech-Trans. Electrochem. SOC. .Trans. Faraday SOG. .Trans.Illinois Acad. Sci. .Trans. Inst. Cham. EngineersTrans. Inst. Metal FinishingTrans. N . Y . Acad. Sci. .?am. J . Plastics Inst. .. vans. Proc. Inst. Rubber Ind.nol., Gothenburg. Roy. SOC. Canada .AZS. Roy. Soc. Edinburghri.ans. Roy. SOC. Trop. Med.Trans. Wisconsin Acad. Sci.HYg*Trudy Inst. Krist., Akad.Trudy Kom. analit. Kliitn.,Nauk S.S.S.R.Akad. Nauk S.S.S.R.Ukrain. biokhirn. Zhur. .Ukrain. khim. Zhur. .Unicam SpectrovisionUS. Bur. Min.Uspekhi Khim. .Verhandel. k. ned. Akad. We-tenschap., A f d . Natuurk.Vestnik Slovensk. Kem.DrustvaVitamins and Hormones .Voprosy Med. Khim. .Wallerstein Lab. Comm. .Wied. Ann. .Z. analyt. Chem.2. angew. Chem.Z. angew. Min. .Z. angew. Phys. .Z. anoug. Chem..2. Biol. .Studii si Cercetari Stiintifice. Chimie. (Academia Re-Studii si Cercetari Stiintifice. Seria I. Stiinte Mate-Suddeutsche Apotheker-Zeitung.Suomen Kemistilehti.Svensk kemisk Tidskrift.Svensk Papperstidning.Symposia of the Society of Experimental Biology.publicii Populare Romine. FiliaIa Iasi.)matice, Fizice, Chimice si Technice.Talanta.Technology Reports of TBhoku University.Technology Reports of the Osaka University.Tetrahedron.Tetrahedron Letters.Textile Research Journal.Tidsskrift for Kjemi Bergvesen og Metallurgi.Transactions of the American Society of Metals.Transactions of the British Ceramic Society.Transactions of Chalmers University of Technology,Transactions of the Electrochemical Society.Transactions of the Faraday Society.Transactions of the Illinois Academy of Science.Transactions of the Institution of Chemical Engineers.Transactions of the Institute of Metal Finishing.Transactions of the New York Academy ofTransactions and Journal of the Plastics Institute.Transactions and Proceedings of the Institution of theTransactions of the Royal Society of Canada.Transactions of the Royal Society of Edinburgh.Transactions of the Royal Society of Tropical MedicineTransactions of the U‘isconsin Academy of Sciences,Go thenbu rg.Sciences.Rubber Industry.and Hygiene.Arts and Letters.Trudv Instituta Kristallorrrafii.Akademii Nauk S.S.S.R.TrudG Komissii PO anaiiticheskoi Khimii, AkademiaNauk S.S.S.R.Ukrainskii biokhimicheskii Zhurnal.Ukrainskii khimicheskii Zhurnal.Unicam Spectrovision.United States Bureau of Mines (Bulletins, TechnicalUspekhi IChimii.Papers and Reports of Investigation).See also Russian Chemical Reviews.Verhandelingen der koninklij ke nederlandsc AkademieVestnili Slovenskega Kemijskega Drustva.Vitamins and Hormones.Voprosy Meditsinskoi Khimii.van Wetenschappen, Afdeling Natuurliunde.Wallerstein Laboratories Communications.Wiedemann’s Annalen der Physik.Zeitschrift fur analytische Chemie.Zeitschrift fur angewandte Chemie.Zeitschrift fur angewandta Mineralogie.Zeitschrift fur angewandte Physik.Zeitschrift fur anorganische und allgemeine Chemie.Zeitschrift fur Biologie572 PRINCIPAL REFERENCES USED.REFERENCE.Z .Elektrochem. .Z . Elektrotech. .Z. ges. exp. Med. .Z. Krist. .2. Lebensm.-Untersuch. .2. Metallk.Z. Naturforsch. .Z. phys. Chem. (Frankjurl) :Z . phys. Chew (Leipzig) .2. Physik2. phys. chem. Unterricht .Z. physiol. Chem. ,Z. tech. Physik .Z . Unters. Lebensm. .Z. Vitaminforsch. .2. Vitamin-, Hormon-, u.Fermentforsck.2. Wirts. Zuckerind. .Z. wiss. Phot. .Zavodskaya Lab.Zentr. Bakt. .Zentr. Min. .Zeszyty Nauk. Politech. lodz. .Zhur. analit. Khim. .Zhur. eksp. teor. Fiz. .Zh.ur. $2. Khim.Zhur. nauk. priklad. Fotograf.Zhur. neorg. Khitia. .Zhur. obshchei Khim. .Zhur. priklad. Khim. .Zhur. tekh. Fiz. .Kinemat. .FULL TITLE.Zeitschrift fur Elektrochemie.Zeitschrift fur Elektrotechnik.Zeitschrift fur die gesammte experimentelle Medizin.Zeitschrift fur Kristallographie.Zeitschrift fur Lebensmittel - Untersuchung undZeitschrift fur Metallkunde.Zeitschrift fur Naturforschung.Zeitschrift fur physikalische Chemie (FrankfurterZeitschrift fur physikalische Chemie. Leipzig.Zeitschrift fur Physik.Zeitschrift fur den physikalischen and chemischenHoppe-Seyler’s Zeitschrift fur physiologische Chemie.Zeitschrift fur technischen Physik.Zeitschrift fur Untersuchung der Lebensmittel.Zeitschrift fur Vitaminforschung.Zeitschrift fur Vitamin-, Hormon-, und Ferment-forschung.Zeitschrift der Wirtschaftsgruppe Zuckerindustrie(Verein der Deutschen Zucker Industrie).Zeitschrift fur wissenschaftliche Photographie, Photo-physik und Photochemie.Zavodskaya Laboratoria.Zentralblatt fur Bakteriologie, Parasitenkunde undInfektionskrankheiten.Zentralblatt fur Mineralogie, Geologie and Palaontologie.Zeszyty Naukowe Politechniki lodzkiej.Zhurnal analiticheskoi Khimii. [See also Journal ofZhurnal eksperimental’noi i teoreticheskoi Fiziki.Zhurnal fizicheskoi Khimii. [See also Journal ofZhurnal nauknoi i prikladnoi Fotografii i Kinematografii.Zhurnal neorganicheskoi Khimii. See also RussianJournal of Inorganic ChemistryZhurnal obshchei Khimii. [See also Journal of GeneralChemistry (U.S.S.R.) .]Zhurnal prikladnoi Khimii. [See also Journal of AppliedChemistry (U.S.S.R.).]Zhurnal tekhnicheskoi Fiziki.(Berichte der Bunsen-gellschaft fur physikalische Chemie.)-Forschung.Ausgabe) .Unterricht.Analytical Chemistry (U.S.S.R.).]Physical Chemistry(U5S.R.) .]PRINTED IN GREAT BRITAIN BY RICHARD CLAY AND COMPANY, LTD.BUNGAY SUFFOLIC

ISSN:0365-6217    

DOI:10.1039/AR9605700557

出版商:RSC    

年代:1960

数据来源: RSC