J. CHEM. SOC. FARADAY TRANS., 1994, 90(9), 1357-1361 Physical Methods of Chemistry. Second Edition. Volume IX 6. Investigations of Surfaces and Interfaces-Part 6. Ed. by B. W. Rossiter and R. C. Baetzold. Wiley-lnterscience, New York, 1993. Pp. xi + 745. Price f206.ISBN 0-471-54405-1. Review series are now commonplace. Notwithstanding the growth of published material in the sciences and the derived technologies, the quality, value and hence the need for some of the series currently available is certainly debatable. However, the model series of which this particular volume is part, in spite of the high cost of its elements (Parts A and B of Volume IX, together: f321/$449) has shown what is attain- able by the circumspect selection of topics, scrupulous choice of contributing authors and meticulous editorial attention. Thus, the publication of the most recent volume of the second edition of the series concerned, Physical Methods of Chemistry, under the editorial stewardship of Rossiter and Baetzold, continues the standards of excellence one has come to expect, i.e.excellence in topic choice, selection of contrib- uting authors, in presentational quality, and consistency of balance between theory, experiment and applications. In the present volume, coverage chapter-by-chapter, within the topics chosen is comprehensive and, given the normal lead time to publication, up to date. Included are eight chap- ters and an index which, while not exhaustive, is certainly more than adequate.Chapter 1 (G. A. Somorjai and M. A. Van Hove, ca. 40 pages) deals with low-energy electron dif- fraction (LEED) in terms of experimental advances, an excel- lent review of 2D structures studied and of the development and application of 3D surface structure determination. Chapter 2 (L. L. Kazmerski, ca. 81 pages) addresses the analysis of surfaces by Auger electron spectroscopy (AES) and related techniques. Overall, this is one of the better recent reviews of Auger-based methods. Almost all one needs to know about the possible applications of AES, energy selec- ted mapping (SAM), chemical speciation and the like is pro- vided, with what can be done set in context. While the emphasis is essentially on current practice and on the techni- cally attainable, the essential fundamentals are not over-looked.Also included is a useful comprehensive bibliography of monographs and texts devoted to surface analysis. Not surprisingly, Chapter 3 (N. H. Turner, ca. 48 pages) follows on dealing, as it does, with the analysis of surfaces by X-ray photoelectron spectroscopy (XPS/ESCA). A short section on basic principles leads into instrumental aspects of the method. An extended consideration of the possible fea- tures which can contribute to an XPS spectrum and of their significance is then given. Quantification, depth profiling, surface derivatisation, angular resolved techniques are all dealt with in some detail. The chapter finishes with a brief but coherent account of the theory of binding energy and energy shifts.Chapter 4 (A. C. Miller, R. B. Irwin and H. F. Helbig, ca. 156 pages) considers low-energy ion scattering (LEIS) and Rutherford backscattering spectroscopy (RBS). The coverage given spans a general introduction, scattering theory in some depth, experimental and instrumental con-siderations, qualitative and quantitative features of LEIS and RBS. Practical applications of both techniques are included, with these drawing on a useful and informative range of examples. Synchrotron sources literally surface in Chapter 5 (D. Norman, ca. 43 pages) which elaborates from first principles the use of X-ray absorption spectroscopy (surface-extended and near-edge X-ray absorption fine structure) at surfaces, i.e. SEXAFS and NEXAFS, respectively. From the basic physics, experimental techniques, sources and detection regimes, are considered, the latter in particular detail.Data analysis, inter- pretation and a representative selection of results complete the chapter. Should the reader wish to see whether their surface science problem can or might be solved using syn- chrotron radiation this would be where to start. Chapter 6 (H. Kuhn and D. Mobius, ca. 167 pages), provides one of the most extensive and thorough reviews available of studies of monolayer assemblies. As such it should be compulsory reading for those already working in the field or wishing to so do. Detailed consideration, both experimental and theo- retical, is given of studies of monolayers at the air/water interface, monolayer dye assemblies, monolayer-substrate interactions, energy transfer phenomena in assembled mono- layers, photoinduction of electron transfer, electrical, electro- optical effects and optical effects, per se.In its turn Chapter 7 (D. A. Scherson and E. B. Yeager, ca. 88 pages) covers the application of spectroscopic techniques to the in situ study of electrochemical interfaces. An adequate introduction to the essential electrochemical background and the optics of interfaces is provided. The short section included on experimental methods usefully tabulates the perceived attributes of the twelve in situ spectroscopic methods reviewed and currently in use. This is followed by sections reviewing adsorption-free interfacial charging and, in more detail, adsorption at the metal/electrolyte interface.Chapter 8 (E. S. Brandt and T. M. Cotton, ca. 85 pages) appraises the surge in recent years of studies of, and involving, the surface- enhanced Raman scattering (SERS) phenomenon. In so doing the relationship between normal and surface-enhanced Raman spectroscopy is dealt with concisely and well. Systems showing SERS are then elaborated, roughened electrodes (nicely complementary to the contents of the preceding chapter), colloidal metal sols, thin metal films and photo- generated silver, in terms of the phenomenon itself and its applications. The requisite instrumentation is also critically discussed. A short resumt: of patented SERS-active substrates and commercial applications is also provided.From the foregoing it is clear that I welcome this volume with enthusiasm. It should be, with its companion volume, Volume IX, Part A, in every scientific library claiming the name. Moreover, it is likely to be in every library serving those with peripheral as well as main stream interests in studies of surfaces and interfaces. Finally, laboratories working specifically in the area of interest, i.e. of surfaces and interfaces, their properties, analysis and characterisation will accept, I believe, that the high purchase price necessary would be money well spent. N.M. D. Brown Received 4th November, 1993 Monographs on the Physics and Chemistry of Materials. 49. Dynamic Light Scattering.The Method and Some Applications. Ed. W. Brown. Clarendon Press, Oxford, 1993. Pp. xvi + 735. Price f95.00 (hardcover). ISBN 0-19-853942-8. ~~ Dynamic light scattering measurements on macromolecular solutions and other systems have been made ever since continuous-wave lasers became commercially available in the mid sixties. The spectral broadening due to phase fluctua- tions resulting from macromolecular motion and changes in configuration is measured, and yields diffusion coefficients and potentially, rotational diffusion coefficients, internal relaxation times and other information. The spectral broadening is of the order of kilocycles and cannot be mea- sured by conventional spectroscopic techniques. It is not to be confused with the much larger shifts due to non-linear effects resulting from vibrational or rotational oscillations in polarizability (Raman scattering).Light scattered from spa- tially random scatterers within a volume having dimensions small compared with the coherence length consists of a random speckle pattern, which changes continuously if the scatterers are moving. If an area of the order of one speckle is observed by the detector, temporal fluctuations in signal are observed which represent homodyne beating between the variously displaced components of the spectrum, and in this way the spectrum can be measured. It has generally been found most convenient to measure the autocorrelation func- tion of the signal. In principle it is not necessary to use a laser, but in order to get sufficient light flux into the necessar- ily small scattering volume, a laser is invariably used. Also because of the low light flux being measured it has been usual to correlate photon counts, since the advent of suitable com- puters in the early seventies, and the technique has become known as ‘photon correlation spectroscopy’. The present volume is concerned, at a fundamental level, with very recent developments, and is suitable only for those who already have some experience in the field.One of the main applications of dynamic light scattering has been in the field of biochemistry, where the technique is often used simply to obtain diffusion coefficients so as to monitor the sizes of biological macromolecules.Many of these workers obtain their results by ‘rule of thumb’, using commercially available equipment, and are unlikely to benefit by reading this book, especially if they have an antipathy to mathe- matics. The book does however contain a short review of applications to biological systems, with over three hundred references to just some of the more interesting recent work. Reference to biological systems is also made in the context of polyelectrolytes (DNA, polysaccharides), rod like macro-molecules (DNA fragments) and rotational diffusion coeffi- cients by depolarized light scattering using Fabry-Perot interferometry (globular proteins); In format the book consists of sixteen chapters on differing subjects, each with a different author.Inevitably there is some overlap, and conventions of mathematical representation are far from standardized, as fashions are continually changing. One quarter of the book is devoted to current methodology, with chapters on photon correlation techniques, noise and data analysis, which should prove useful to those wishing to be brought up to date in these matters. New theories and experiments with polymers and polymer mixtures in dilute solution, semi-dilute solution, and in the bulk, are dealt with extensively in variously entitled chapters, and there are chap- ters on depolarized light scattering (misleadingly titled) and polyelectrolytes. Other systems dealt with (one chapter each) are gels, rod-like macromolecules (with some reference to liquid crystals) and micelles.There are also chapters describ- ing investigation of the critical dynamics of fluids and liquid mixtures by dynamic light scattering, and multiple scattering by dense media (diffusing wave spectroscopy). In conclusion the book is to be recommended to workers with some experience in the field as a reference to recent developments. D. B. Sellen Received 8th November, 1993 J. CHEM. SOC. FARADAY TRANS., 1994, VOL. 90 Reflections on Symmetry. By El Heilbronner and J. D. Dunitz. VCH, Weinheim, 1993. Pp. iv + 154. Price €22. ISBN 3-527-28488-5. Symmetry is the strongest unifying concept in chemistry. Consciously or unconsciously, it pervades most of the activ- ities of chemists. Of ancient origin, the power of symmetry arguments began to be realised by physicists and chemists in the 1920s, but it was not until the early 1960s that textbooks readily accessible to undergraduates and non-specialists began to appear.Today there are dozens of texts dealing with symmetry at all levels of detail. This is not a textbook. It had its origins in a lecture given by Heilbronner in 1980 as the first of a series dealing with the border areas between art and science and aimed at a non- specialist audience. This lecture has been expanded and lav- ishly illustrated. The result has something of the style of a ‘coffee table’ browser; it is aimed at chemists but with at least an eye on a wider audience. Somewhat curiously, the publi- sher’s dust jacket suggests that a likely audience is ‘older chemists (who) may be at a disadvantage’ because they ‘feel that their encounter with symmetry concepts during their student days was inadequate’.It seems to me that this audi- ence is precisely one where the necessary limitations of the style adopted would be most frustrating. Such a readership would be better advised to read one of the standard texts. The authors recognized the problem inherent in their approach : “One difficulty we have to face is that the interconnection between the playful aspect of symmetry on the one hand and an exact science is not at all simple. ... This makes it difficult to steer a secure course between the Scylla of irre- sponsible superficiality and the Charybdis of unintelligible jargon.. . . A treatment rigorous enough to satisfy finicky criticism of the experts and at the same time gentle enough for the non-specialist is just not possible in the limited space available”. As a result, the choice of material is idiosyncratic and the phrasing sometimes curious. For example ‘the reflection in a calm mountain lake’ is referred to as ‘fortuitous symmetrization’ (p. 5) and one wonders why Rafael’s ‘Alba Madonna’ was chosen (p. 9) to illustrate the underlying com- positional symmetries in paintings in preference to the same artist’s ‘Madonna of the Meadows’ or a work of Piero della Francesca. The symmetry of atoms and the deeply satisfying relationship of the periodic table to rotational symmetry is not mentioned.Indeed how the symmetry of s-and p-orbitals (p. 139) relates to the spherical symmetry of atoms will leave some readers confused. A recurring theme is that sometimes nature adopts the highest possible symmetry, whereas in others the experimen- tally determined symmetry is lower than one might (naively) have expected. One example quoted is benzene and cyclo- octatetraene, but the underlying symmetries of the orbital structures are not explained, which might have found a place in Chapter 10. By contrast Chapter 9 on chirality seems unnecessarily extended, but still fails to explain the relation- ship between the rotation of the plane of polarised light and the molecular (lack of) symmetry. Overall the fears of the authors seem justified, this book does not succeed in achieving its very ambitious object.It is too long and too detailed (in parts) to be merely a stimu- lation, but too short and too superficial for the reader to obtain any real understanding. It is, however, a brave attempt and will benefit two groups of readers. First, teachers in higher education will find the examples (with some less J. CHEM. SOC. FARADAY TRANS., 1994, VOL. 90 than well known references), and especially the figures, a welcome source of different ways to present symmetry to stu- dents. Secondly, students meeting symmetry for the first time and working through a formal treatment might find the ‘playful’ approach a welcome diversion. It will certainly raise tutorial questions.The cost of the book is very reasonable considering the very high standard of production. C.D. Flint Received 18th November, 1993 ~~ Advances in Chemistry Series 229. Magnetic Reson- ance of Carbonaceous Solids. Ed. R. E. Botto and Y. Sanada. American Chemical Society, Washington, DC, 1993. Pp. xiv + 664. Price $149.95. ISBN 0-8412-1866-8. This book is an excellent compilation of research papers on ‘H and ’3C NMR and electron paramagnetic spectroscopies. Although based on papers to a Chemical Congress of the Pacific Basin Societies in 1989, these versions of the papers are more up to date. Most of the manuscripts were submitted in mid-1990, with acceptance of revised versions up to the end of 1991 and with publication in 1993.There are very few typographical errors and the production is to the high quality typical of the Advances in Chemistry Series of the ACS. One minor irritation (for this reviewer) which might have been avoided in the editorial process is the inclusion of the elemental analyses of the Argonne Premium Coals in eight of the 33 papers. In some of the eight papers, these data are quoted as from the handbook and given to two decimal places for carbon; in others, they are given to the same apparent accuracy but with no clear comment that they were taken from the handbook; two papers quote dmmf basis (dry, mineral matter free) and the other six quote daf basis (dry, ash free), but do not all make clear which basis applies, while in only one paper are the carbon daf values rounded to one decimal place.Most coal scientists will of course be able to cope with this, but the data could have been summarized conveniently into one table in an Appendix, if it was felt vital to include it at all. Of the 33 papers, seven are devoted to overviews of the techniques: quantitation in I3C NMR of solids; ‘H NMR of solids ; NMR and dynamic nuclear polarization spectros- copy; electron nuclear double resonance spectroscopy; elec- tron spin relaxation measurement ; multifrequency electron paramagnetic resonance spectroscopy; and high-temperature electron paramagnetic resonance and NMR methods. Fifteen papers cover more specific aspects of NMR and coal, such as, the submicroscopic structure of bituminous coals, pyridines sorbed onto coal, principal component analysis of relaxation times, coal liquifaction residues, oxida- tion effects, problems of quantitation, magic-angle-spinning and high-field studies.Ten papers cover electron paramagnetic resonance spec- troscopy applied to the Argonne coals and solvent-swelled coals, using variable microwave frequencies and electron spin-echo methods. The final paper is a thoughtful conclusion on the state of the art of the application of magnetic resonance methods to coal. The importance of the Argonne set of coals, free from drying and oxidation up to the point of opening the sealed ampoules, is emphasised and these studies reveal much about the coal structure. However, there is still a lot to be done on low-rank coals, as this paper makes clear, with a need for a larger number of coals, particularly low-rank coals, as a data- base for the kind of comparison undertaken by this volume.This book is not a light read; it contains a great deal of detail about the techniques, their drawbacks and their appli- cation to coal. The contrast between what they reveal about coal structure and what remains to be investigated, as seen by this collection of distinguished scientists, should ensure that this book will find a place in both the institutional libraries and in the personal libraries of coal scientists, even if they are not active in the particular fields of magnetic resonance covered. A. A. Herod Received 24th November, 1993 Spectroscopy of the Earth’s Atmosphere and Inter-stellar Medium.Ed. K. N. Rao and A. Weber. Aca-demic Press, London, 1992. Pp. xi + 526. Price $129.5. ISBN 0-12-580645-0. The Editors of this book, the fourth volume of ‘Molecular Spectroscopy: Modern Research’, have endeavoured to choose a set of contributed articles relevant to the theme of atmospheric and interstellar spectroscopy. The articles are weighted heavily in favour of atmospheric spectroscopy, with authoritative reviews of far infrared and microwave spectros- copy by Carli and Carlotti and of infrared spectroscopy of Brown, Farmer, Rinsland and Zander. Since Farmer has been one of the pioneers in this area as the driving force behind the ATMOS infrared Fourier transform spectrometer, Chapter 2 makes fascinating reading.The third and fourth chapters on intensities and collisional broadening parameters, and on collisional line mixing, while not devoted to atmospheric spectroscopy directly, discuss the information which is necessary to derive concentration data from the type of spectra produced by current high-resolution spectrometers. The first of these by Smith, Rinsland, Malathy Devi, Rothman and Rao contains an extensive list of param- eters for use in concentration retrievals, whereas the second by Levy, Lacombe and Chackerian discusses the effects of collisions on redistributing energy level population and its effects on intensities, the popular topic of collisional line mixing.The final chapter in the compilation, spectroscopy among the stars, by Winnewisser Herbst and Ungarechts gives a fas- cinating introduction to current uses of rotational spectros- copy for probing the interstellar medium, showing clearly the interplay between spectroscopy, chemistry and astrophysics. By using one or two molecules as vehicles for the discussion, for example carbon monoxide as a tracer for molecular clouds, the authors have shown clearly how the detective work necessary to unravel the physics of these regions is being conducted. The penultimate chapter on spherical top spectra by Champion, Loete and Pierre gives an authoritative survey of spherical tensor methods and of the contact transformation approach to our understanding of the spectra of spherical top molecules.However, although methane is a molecule which is found in the atmosphere, I feel that this contribution, although well written, does not fit in very well with the theme of the rest of this review volume. In summary this book is an up to date and authoritative review of the role of molecular spectroscopy in furthering the understanding of the atmosphere of our planet and of the interstellar medium. It is clearly written and well illustrated and will serve as a useful introduction to current ideas about these aspects of earth observation and molecular astro-physics. G. Duxbury Received 24th November, 1993 Magnetism and Optics of Molecular Crystals. By J. W. Rohleder and R. W. Munn.John Wiley & Sons Ltd., Chichester, 1992. Pp. x + 139. Price f29.95. ISBN 0-47 1-93 17 1-3. As the title indicates, this short text (three chapters and 137 pages) is a monograph on a specialised aspect of molecular physics, limiting itself to the diamagnetism and non-dispersive optical properties of molecular crystals. The book is in part based on graduate lectures given by the authors, and as well as providing a suitable background to the topics discussed, it contains much of the authors’ original contribu- tions to this research area. The feature of molecular crystals explored in this mono- graph is the relationship between properties of molecules and the macroscopic magnetic and optical properties of their crystals. There are two aspects to this problem: (i) the spatial distribution of molecules and their relation to crystal sym- metry axes and principal axes of the magnetic susceptibility and optical permittivity, and (ii) the dependence of the molec- ular properties on crystal environment, either through long range or short range interactions.By focussing on dia-magnetic properties, complications of intermolecular inter- actions can be ignored, and the oriented gas model is a valid basis for the molecular interpretation of the diamagnetism of molecular crystals. Both magnetic susceptibility and electric permittivity are second rank tensors, and Chapter 1 provides a useful discussion of their symmetry and transformation properties. Chapter 2 on diamagnetism includes a section on classical methods of measurement, but this is too brief to be of any real value, and misses an opportunity to introduce more modern methods, such as SQUID magnetometry, which may lead to a revival of interest in magnetic properties of molecules.Examples are given of the analysis of crystal susceptibilities to give components of the molecular dia-magnetic susceptibility, and the chapter concludes with a table presenting data for 40 compounds. In contrast to magnetic properties, the interpretation of the electric response of materials in terms of molecular properties is seriously complicated by the internal field problem. This is important even for optical properties, because the corre-sponding permittivity is at least twice the value for free space.Anisotropy of molecular crystals adds a further difficulty, since the long-range polarization which is responsible for the internal electric field now depends on orientation, and indeed crystal shape. This problem has been actively researched over the past 20 years by the authors and others, and is essentially solved, at least in a formal sense. Chapter 3 gives a detailed description of wave propagation in crystals, and contains a clear account of double refraction together with a brief review of some classical methods for measuring birefringence. The major part of this chapter is devoted to the determi- nation of components of the molecular polarizability tensor from principal refractive indices using a proper representa- tion of the internal electric field and plausible models for the local molecular polarization ;results are given for a number of well studied ’ molecular crystals.The chapter concludes with a short section on the non-linear optics of molecular crystals, accounts of which are, as the authors remark, ‘paradoxically more commonly available than those of the linear optics ’. The objects of study for chemists and molecular physicists are molecules: in molecular crystals they are trapped in a regular array, so their features can be examined in detail, without recourse to statistical averaging. In the pursuit of molecular electronics, molecular engineering, nano-(ie. molecular-scale) technology, it might be supposed that molec- J.CHEM. SOC. FARADAY TRANS., 1994, VOL. 90 ular crystals would be the focus of applied research, but the reality is different, and molecular crystals remain in the prov- ince of theoreticians and dedicated experimentalists. Perhaps the situation will change, and if it does this small book will be a useful starting point for the understanding of the proper- ties of molecular crystals. At present because of the special- ised nature of its subject matter, it is unlikely that this book will have a wide appeal, but it can be recommended to grad- uate students and other researchers in the field as a useful source book and valuable teaching aid. D. A. Dunmur Received 24th November, 1993 Photodissociation of Simple Molecules in the Gas Phase. By H.Sato. Bunshin, Tokyo, 1992. Pp. v + 158.Price (incl. postage) %2,060, $17.50 (USA); % 2,290, $19.50 (Europe). ISBN 4-89390-092-7. The last two decades have witnessed an extraordinary growth both in the range and in the sophistication of experimental techniques available for unravelling the intimate details of simple gas-phase reactions. Molecular photodissociations represent one major subset of this area of research. For con- firmation that this remains an active, exciting and challenging research area, one need do no more than scan the contents pages of any of the latest issues of the major physical chemistry/chemical physics journals. What are the require- ments of those researching molecular photodissociation dynamics? Good equipment (if experimentalists), computer time (if theoreticians), a sound understanding of molecular spectroscopy and molecular quantum mechanics, of photo-chemistry and reaction dynamics, and a good knowledge of what has gone before. For modern photochemists, Okabe’s book Photochemistry of Small Molecules (Wiley), published in 1978, has been an invaluable source of background know- ledge.However, much has been discovered in the intervening years and there is now a pressing need for an updated version of this book. Suto’s book goes some way to fulfilling this need. It pro- vides a comprehensive bibliography of (largely experimental) papers published in the period 1970 through 1991 in the area of gas-phase molecular photodissociation dynamics.It pro- vides a distillation of the contents of more than one thousand references covering the primary photochemistry of 284 small molecules and 70 or more van der Waal’s species. Entries concerning any one molecule are grouped together, and appear in (roughly) chronological order. As a representative illustration of the information provided in each entry I select the classic paper on the near UV photolysis of HONO by Vasudev, Dixon and Zare (J. Chem. Phys., 1984, 80, 4863). This one or more man years of work is compressed to: HONO 369,355,342 LIF OH(X ’H): V(cold), R(cold, N < 7), F*(F2 preference), A, alignment, split Doppler profile thereby giving information on the photolysis wavelengths studied, the particular fragment species probed and the probing method employed, the deduced internal energy dis- posal within the probed fragment and an indication of the vector properties (alignment, recoil velocity) measured.The compilation is comprehensive, but not critical. For example, the early time-of-flight study of ICN photolysis at 266 nm (which concluded that the two observed peaks indi- cated the formation of both ground and electronically excited CN fragments) is listed in just the same way as the many subsequent papers which have shown that the two peaks are actually due to electronic branching in the companion atomic J. CHEM. SOC. FARADAY TRANS., 1994, VOL. 90 iodine photofragment. The book thus provides a source of references in much the same way as would be obtained from searching a data base. The present work is, of course, much more than just a bibliography, since it provides an (accurate) summary of the results reported in each paper. However, it cannot be viewed as a replacement for Okabe’s book, or for Herzberg’s classic text, Molecular Spectra and Molecular Structure III, Electronic Spectra and Electronic Structure, because it offers no critical overview of the various cited works. These reservations notwithstanding, Suto’s book is a valu- able addition to the photochemical literature. It is accurately produced and very reasonably priced. Many will share my hope that the author will wish to offer periodic updates to this compilation. Maybe the next edition will appear on disk; the material seems ideally suited to distribution in this way. M. N.R. Ashfold Received 25th November, 1993