22 New Compounds and Structures By J.T.S. IRVINE Department of Chemistry University of Aberdeen Meston Walk Aberdeen AB9 2UE UK 1 Introduction The aim of this review is to highlight new and exciting phases and structures that have been reported in 1992. It is hoped both to reflect current trends in solid state chemistry and to provide some insight into future advances in this important area. The scope of this review is limited to inorganic materials with reasonably defined composition and structure. New compounds formed solely by solid-solution formation have not been reported. The organization of this review is based on both structural and chemical aspects. Division is largely by periodic classification with the primary split being between oxides and non-oxides.Oxides are further sub-divided into transition metal oxides main group oxides and important structural families. Where overlap occurs classifica- tion has been made to maximize the coherence of the current year's report. 2 Overview The number of new phases and structures reported in the last year reflects the continued high level of activity in solid state chemistry. There are some perceptible changes in emphasis; for instance there is a clear increase in activity in non-oxide chemistry particularly in halide nitride and chalcogenide chemistry. Activity in the area of cuprates has decreased somewhat; however this appears to be just a temporary lull. Low-dimensional structures and the perovskite structure continue to be key areas of interest.3 Transition Metal Oxides Vanadates and Titanates.-Two new hexavanadates SrV,O ,and NaV,O which are isostructural with Ba,Ti,Fe,O ,,and hence structurally related to magnetoplum- bite have been reported.' A new bismuth magnesium vanadate BiMg,VO, with Mg in an unusual five-fold geometry has been synthesized. The structure of BiMg,VO may be viewed as consisting of chains of edge-shared BiO groups and corner-shared MgO square pyramids. These chains are connected through.VO tetrahedra and uia ' Y. Kanke K. Kato E. Takayama-Muromachi and M. Isobe Acta Crystallogr. Sect. C 1992,48 1376. * J. Huang and A. W. Sleight J. Solid State Chern.. 1992 100 170. 409 410 J. T.S. lrvine edge-sharing of the MgO groups Figure 1. A bismuth strontium vanadate containing both orthovanadate and pyrovanadate groups has also been rep~rted.~ C a a’ Figure 1 Structure of BiMg,VO (Reproduced by permission from J.Solid State Chem. 1992 100 170) Several new metal vanadates with formula M,V,O have been reported. A high-pressure form of Mn,V,O with the pyrochlore structure has been ~repared.~ A high-temperature form of strontium pyrovanadate containing two types of V,O unit has also been reported. No V,O groups were found in the structure of ThV,O, instead the structure was observed to contain both independent VO groups and infinite chains of corner-shared VO tetrahedra Figure 2.6 The hydrogen analogue of the lithium titanate ramsdellite phase H2Ti30, has been prepared by simple proton exchange.’ The structure of the new phase NaGaTi,O has been shown to be related to that of Na,Ti,O , consisting of a framework of NaO and GaO octahedra which form tunnels accommodating the Na ions.’ A new titanate phase which exists over a range of stoichiometry Ba3xLi,x+,,Ti8 -2x-y016 0.32 < x < 0.40 and 0 < y < 0.2 with a structure closely related to the Priderite member of the Hollandite family has been characterized.’ J.Huang and A. W. Sleight. J. Solid Stute Chem. 1992 97 228. M. A. Subramanian Mat. Res. Bull. 1992 27 939. J. Huang and A. W. Sleight Mat. Res. Bull. 1992 27 581. S. Launay P. Mahe M. Quaton and F. Robert J. Solid State Chem. 1992 97 305. ’ A. LeBail and J. L. Fourquet Mat. Res. Bull. 1992 27. 75. ’ Y. Michiue. M. Watanabe Y. Kitami and Y.Fujiki. Acta Crystallogr.. Sect. C 1992 48 607. ’C. Suckut R.A. Howie A. R. West and L. M. Torres-Martinez. J. Muter. Chem. 1992 2 993 New Compounds and Structures 41 1 ..... Th ..... 2(VO3)O ..... Th ..... V04 ..... vo4 _....Th ..... 2(V03) ..... Th ..... vo4 ..... vo4 ..... Th Figure 2 Projection of structure qfThV,O along [Ool] (Reproduced by permission from J. Solid State Chem. 1992 97 305) Cuprates.-Although interest in superconducting cuprates has decreased from its highpoint in the late 80s there is still intense interest in cuprate perovskites and perovskite intergrowth phases. Some of the most interesting chemistry has been in the development of novel oxygen-deficient perovskites. Ba,La,Cu,Sn,O is a new oxygen deficient quadruple perovskite whose average structure Figure 3 can be described by a tetragonal cell; however because of rotational ordering of SnO octahedra about c a long range modulation is also observed.' A number of rare-earth strontium gallium cuprates e.g.LaSrGaCuO, exhibiting the well-known oxygen deficient perovskite-related Brownmillerite structure have also been reported. Another new perovskite YBaCoCuO, has a similar formula; however its structure which is analogous to YBaFeCuO, contains both B-cations in square pyramidal coordination instead of having one B-cation in octahedral geometry and the other in tetrahedral geometry as occurs in Brownmillerite. l2 Rouillon et a!. have prepared PbBaSrYCu,O with a structure built up from triple M.T.Anderson K. R. Poeppelmeier. J.-P. Zhang H.-J. Fan and L. D. Marks Muter. Chmi.. 1992. 4. 1305. G. Roth P. Adelmann R. Knitter S. Massing. and Th. Wolf J. Solid State Chem. 1992. 99. 376. '2 L. Barbey N. Nguyen V. Caignaert H. Hervieu and B. Raveau Mat. Res. Bull. 1992 27 295. 412 J. T.S.irvine perovskite and single rocksalt layers.13 Rouillon et ul. have also determined the structure of PbBa,,,Sr ,,PrCeCu,O, finding it to be a perfectly ordered intergrowth of single and double oxygen-deficient perovskite layers with single rocksalt and double fluorite type layers. l4 A new layered cuprate (Y,Ce),SrFeO, containing a triple fluorite layer has been reported.' The Thorium analogue of the fluorite related Ce-223 superconductor La,Ba ,,,Th,,,,Cu,O +y has also been prepared.' Figure 3 Poljihedrul representation of the structurr of Ba,La,Cu,Sn,O ; large spheres Ba; medium spheres La; smallest spheres 0 uacancies; octahedra SnO ;and square pyramids CuO (Reproduced by permission from Mater.Chem. 1992 4 1312) A copper oxycarbonate containing infinite CuO layers Sr ,,Ba,,,CuO,(CO,) has been synthesized and its structure determined.' Other First Row Transition Metal Oxides.-An oxygen-deficient perovskite La,LiMnO,.,, with some of the manganese apparently in the (v)oxidation state has been reported.' The hypomanganate RbBaMnO, which is also MnV has been prepared and its structure found to be isotypic with fi-K2SO4.l9A new layered 13 T. Rouillon V. Caignaert. M. Hervieu. C. Michel. D. Groult and B.Raveau J. Solid State Chem. 1992,97. 56. 14 T. Rouillon V. Caignaert. C. Michel M. Herbieu D. Groult,and B. Raveau. J. SoM State Chem. 1992,97 19. 15 E. M. Kopnin A. V. Mironov L. M. Kovba L. G. Akselrud I.G. Muttik and V. V. Moschalkov J. Solid State Chem. 1992. 100. 30. 16 L. Rukang T. Kaibin Q. Yitai. and C. Zuyao. Mur. Rrs. Bull. 1992 27 349. 17 A. R. Armstrong and P. P. Edwards J. Solid Stute Chem. 1092 98 432. 18 G. Demazeau E. 0.Oh-Kim J.-H. Choy. and P. Hagenmuller. J. Solid Srute Chem.. 1992 101. 221. 19 D. Fischer and R. Hoppe J. Solid Stute Chrm. 1992 96 7. New Compounds and Structures compound (Fe,Mn)Ta(O,)O, with the metals in an unusual trigonal prismatic coordination has been preparede2' Reduction of lanthanum strontium nickelates with the K,NiF structure has been found to give rise to phases retaining an oxygen-deficient K2NiF structure with most of the Ni in the + 1 oxidation state e.g.SrLaNi0,,,.2' A low-temperature modification of LiCoO has been prepared by reaction of the carbonates this modification has a similar layered structure to the high-temperature form; however because of the occurrence of some Co atoms in the Li layer the electrochemical properties are significantly different .22 Second and Third Row Transition Metal Oxides.-A new lanthanum molybdate La4Mo2OI1 has been found to be isostructural with Nd,Re,O,,; the structure is based on the packing of quasi-linear chains of Mo,O units and La atoms Figure 4.23 A new cation-ordered derivative of the rutile structure has been observed for COR~O,.~ Figure 4 Structure of La,Mo,O ,; smallest spheres Mo.(Reproduced by permission from Acta Crystallogr.. Sect. C. 1992. 48 1915) A series of new hexagonal perovskites Ba,Ru,MO, (M = Li Na Mg Zn) has been synthesized2' and the structures of the Na and Li members of this series refined. In both cases all the face-sharing octahedral sites are occupied by Ru; however in the structure of the Na member Ru and Na are 1 1 ordered over the corner-sharing octahedral sites giving an 8-H structure Figure 5 whereas in the Li member the more usual 6-H structure with Li and Ru disordered over the corner-sharing sites is found. D. Shuiquan Z. Honghui and H. Jinling J. Solid Srurcj Chetn.. 1992. 98 40.21 M. Crespin. C. Landron P. Odier J. M. Bassat P. Mouron. and J. Choisnet J. Solid Srute Chem.. 1992. 100. 281. z2 R. J. Gummow M. M. Thackeray W. I. F. David. and S. Hull Mat. Rrs. Bull.. 1992. 27. 327. 23 P. Gall and P. Gougeon Actu Crj.xtullopr. Sect. C 1997 48. 1915. '' W. H. Baur W. Joswig G. Pieper and I). Kassner. J. Solid Srurr Chem. 1992. 99. 207. 2s P. D. Battle. S. H. Kim and A. V. Powcli J. Solid Srtrrr Ch~m..1992. 101. 161. 414 J. T.S.Irvine A number of copper(u)/ruthenium(v) compounds of La and Sr Sr,LaRuCu + (n= 1,2,3),exhibiting structures ranging from perovskite via the Ruddleston-Popper A3B20 to the K,NiF structures have been reported.26 Two more Ru Ruddles- ton-Popper phases Sr,FeRuO and Sr,FeRuO, have also been reported., as have two new Sc Ruddleston-Popper phases SrLaScO and S~L~,SC,O,.~' Figure 5 The 8H-perovskite structure of Ba,Ru,NaO 2.Lightly hatched octahedra contain Na atoms hatched octahedra contain Ru and circles are Ba (Reproduced by permission from J. Solid State Chem. 1992 101 161) 4 Perovskites Perovskites and perovskite-related structures have already featured heavily in the previous section and will again be covered in the bismuthate section. Here we mainly focus on mixed-perovskite phases where it is difficult to define a primary functional species. Two new ordered cubic double perovskites Sr,Fel"BiVO and Ba,PrPtO, have Two been re~orted.~~,~' new antiferromagnetic perovskite-related materials SrLaFeSnO and SrLaNiSbO, have also been prepared.j' Two new oxygen-deficient perovskites with Co replacing Cu in the Cu0,-plane sites in the YBa,Cu,O structure LaBa,CoCu,O,, and LaBa,Co,CuO, have been reported., A new series of hexagonal perovskites ALa,Ti,RuO, (A = Ca Sr Ba) isostructural with 26 M.P. Attfield P. D. Battle S. K. Bollen S.H. Kim A. V. Powell and M. Workman J.Solid State Chem.. 1992 % 344. 21 P. D. Battle S. K. Bollen and A.V. Powell J. Solid State Chem. 1992 99 267. 28 I.-S. Kim H. Kawaji M. Itoh and T. Nakamura Mat. Res. Bull. 1992 27 1193. 29 S. H. Byeon T. Nakamura M. Itoh and M. Matsuo Mat. Res. Bull. 1992 27 1065. 30 U. Almador C.J. D. Hetherington E. Moran and M. A. Alario-Franco J. Solid State Chem. 1992,96 132. 31 M. P. Attfield P. D. Battle S. K. Bollen T. C. Gibb and R.J. Whitehead J. Solid State Chem. 1992,100 37. 32 M.S. Hegde K. M. Satyalakshmi S. Ramesh N.Y. Vasanthacharya and J. Gopalkrishnan Mar. Res. Bull. 1992. 27 1099. New Compounds and Structures Ba,Nb,O,, have been ~haracterized.~~ The crystal structure is of the 5-H polytype with an hccch sequence along the c-axis Figure 6. Figure 6 The SH-perouskite structure of CaLa,Ti,RuO (Reproduced by permission from Mat. Res. Bull. 1992 27 931) 5 Main Group Oxides Berates.-A novel orthoborate with a non-centrosymmetric structure based on a three-dimensional framework of ZnO tetrahedra and BO triangles BaZn (BO,), has been ~ynthesized.~ Sr,(BO,),Cl has been found to have an intricate framework structure based on SrO,Cl, SrO,Cl, SrO, and BO groups., The structure of LiBa,B,O, has been found to be based on a novel (B,0,,)5- unit,composed of three BO triangles and two BO tetrahedra.36 Silicates and Germanates.-LiBSiO has been prepared hydrothermally ;the resulting structure can be described as cristobalite-like with Li occupying tetrahedral sites.,’ The crystal structure of a new lithium alumino-silicate and a series of Ga/Ge analogues Li,ABO (A = Al Ga; B = Si Ge) have been determined.38 This structure is based on a hexagonal close-packed array of oxygen atoms with cations disordered over one set of tetrahedral sites and can be described either as a cristobalite-like sheet structure or as a wurtzite superstructure.Two silicate structures containing four-membered rings of SO tetrahedra have 33 N.Bontchev F. Weilt and J. Darriet Mat. Res. Bull. 1992 27 931. 34 R. W. Smith and D. A. Keszler J. Solid State Chem. 1992. 100 325. 35 T. Alekel and D. A. Keszler Acta Crysrallogr. Sect. C. 1992 48 1382. 36 H. Qingzhen L. Shaofang D. Guiqin and L. Jingkui Acta Crystnllogr. Sect. C 1992 48 1576. 37 J. B. Parise and T. E. Gier Chem. Mater. 1992 4 1065. 38 J. M. S. Skakle J. G. Fletcher A. R. Honie and A. R. West. J. Solid State Chem. 1992 98 33. 416 J. T.S. Zruine been described. K,(NbO),Si,O, has a tetragonal structure based on chains of NbO octahedra linked together by Si,O ,single rings.39 BaCuSi,Olo has been prepared by two sets of worker^.^^,^* Both groups found that the structure consisted of rings of four linked SiO tetrahedra and was isotypic with mineral Gillespite BaFeSi,O ".Phosphates and Arsenates.-A series of lan thanide caesium europium(i1) phosphates CsEuLn(PO,) (Ln = La Ce. Pr. Eu Th) exhibiting a rhabdophane hexagonal structure have been prepared., The Nasicon-related Cu' compound CuZr,( has been reported.43 Quite a number of vanadium and niobium phosphate compounds have been reported. These include Ca(VO),(PO,),. which crystallizes in a non-centrosymmetric point group and shows some similarity in structure to the important non-linear optical material KTiOP0,.44 Another oxophosphate is CaNb,P,O ,,the structure of which contains double layers of zig-zag corner-sharing chains of NbO octahedra connected by layers of PO tetrahedra and Ca ions Figure 7.45 A new vanadium phosphate BaV,P,Olo with a tunnel structure in a (V,P,O,,) framework has been isolated;, another barium vanadium phosphate has also been reported Ba(VO,)PO, with a Figure 7 Structure of CaNb2P20,, showing mixed fiame\t'ork of double-layered zig-zag NbO chains and corner-shared phosphate groups (Reproduced by permission from J.Solid Stair Chem. 1992 98 174) 3'1 M. P. Crosnier D. Guyomard. A. Verbaere. Y. Piffard and M. Tournoux J. Solid Sture Chem. 1992.98 128. 4" H.C. Lin F.L. Liao and S. L. Wang Actu Crysfullogr.. Sect. C 1992 48 1299. 41 J. Janczak and R. Kubiak Actu C'rj.stalloyr.. Sect. C. 1992 48 1299. 42 G. Wu. M. Jansen and K. Konigstein J. Solid State Chem. 1992 98. 210. 43 I. Bussereau M. S. Belkhira. P. Gravereau R. Boireau J. L. Soubeyroux.R. Olazcuaga and G. Le Flem. Actu Crystullogr. Sect. C. 1992 48 1741. 44 K. H. Lii. B. R. Church H. Y. Lang and S. L. Wang J. Solid Sfnfc. Chem.. 1992 99 72. 45 D. L. Serra and S.-J. Hwu. J. Solid Srure Chem.. 1992. 98 174. 4h A. Grandin J. Chardin M. M. Borel A. Leclaire and B. Raveau .I. Solid Srute Chem. 1992. 99. 297. New Compounds and Structures structure based on layers of phosphate tetrahedra and edge-shared bioctahedra of distorted VO Two novel niobium phosphate bronzes K,Nb,P,SiO, and Bao,8,Rb,Nb8P,0,, and the Langbenite K 1P18073 have been A new mixed-valence vanadium phosphate KV,P,O 7 containing intersecting six-sided and Brownmillerite zig-zag tunnels has been ~repared,~ and a tetravalent vanadium diphosphate Na,VP,O, has been reported.52 Two new cyclophosphate salts of silver have been reported.Ag,NaP802,- (N0,),.4H20 contains the P80; ring anion5 and Ag4K,P,,0,,~10H,0 contains the PlOO~~- anion Figure 8., W d 0 0 0 Figure8 Projection along b of the structure of Ag,K,P,oO,,~lOH,O.In increasing order ofsize the circles represent siluer atoms potassium atoms and water molecules (Reproduced by permission from J. Solid State Chem. 1992 97 299) The structure of a novel vanadyl(1v) orthophosphate hydrate (VO3)(PO,),-9Hz0 has been solved showing it to be a corrugated layered structure consisting of large ‘squares’ of (VO,-PO,-) moieties with water molecules located in the open cells Figure A new phosphate hydrate Nio,,VOP0,~l~H20 has been prepared hydr~thermally.~~ Bismuthates and P1umbates.-The crystal structure of CaBi,O has been deter- mined.57 Unlike many of the ternary bismuthates in the series containing the bismuth cuprate superconductor system the alkaline-earth ions are found in the same layers as the bismuth ions occupying every third cation position when viewed along b Figure 10.Crystals of the cubic perovskite phase KBiO have been prepared by electrolysis of molten KOH containing Bi,O,.” A number of new Bi” phases {LiSr,BiO, NaSr,BiO, NaBa,BiO,) {Li6KBi06 Li,RbBiO,) and { Li,Ba,Bi,O >,exhibiting 47 H.Y. Kang S. L. Wang and K. H. Lii Acta Cr-vstallogr. Sect. C. 1992 48. 975. 4x A. Leclaire M. M. Borel J. Chardon A. Grandin and B. Raveau Acta Crystallogr. Sect. C. 1992.48 1744.4y C. Gueho M. M. Borel A. Grandin A. Leclaire and B. Raveau Actu Crystallogr. Sect. C 1992.48 2066. 50 A. Benmoussa M. M. Borel A. Grandin. 4. Leclaire and B. Raveau. J. Solid Stare Chem. 1992.97. 314. 51 L. Benhamada. A. Grandin M. M. Borel A. Leclaire and B. Raveau. J. Solid State Chem.. 1992.97 131. 52 L. Benhamada A. Grandin M. M. Borel. A. Leclaire and B. Borel J. Solid State Chem. 1992 101 154. 53 M. T. Averbuch-Pouchot and A. Durif Acta Crystallogr.. Sect. C. 1992. 48 1173. 54 M.T. Averbuch-Pouchot A. Dunf and 1J. Schulke J. Solid Stare Chem.. 1992 97 299. 5s B. G. Teller P. Blum E. Kostiner and J. A. Hriljac. J. Solid Stute Chern. 1992. 97 10. s6 K. H. Lii and L. F. Mao J. Solid State Chem. 1992 96. 436. 57 T. A. M. Haemers D. J. W. Haemers.D. J. W. Ijdo and R. B. Helmholdt Mar. Rex Bull.. 1992.27 1243. sH S. Kodialam V.C. Korthius R.-D. Hoffmann and A. W. Sleight. Mat. Res. Bull. 1992. 27 1379. 418 1.T.S. Irvine Figure 9 Representation of the structure of (VO),(PO4),*9H,O;jfilled spheres PO tetrahedra; open ellipsoids VO octahedra (Reproduced by permission from J. Solid State Chem. 1992 97 10) Figure 10 Projection of crystal structure of'CaBi,O along b (Reproduced by permission from Mat. Res. Bull. 1992 27 1243) three distinct structure types each of which contain perovskite-derived units have been prepared by hydroxide flux The structure of Li2Ba,Bi20 1,Figure 11 is based on zig-zagged chains of corner-sharing BiO octahedra running parallel to b. Two new plumbate pyrochlores the red insulating Bi,Pb,O and the rhombohedrally distorted black metallic TI2Pb20, have been prepared by high-pressure oxygen synthesis.,' A new mixed-valence Aurivillius-type phase Bi,V .5Sb,.50 ',,,has been reported.61 A number of bismuth-containing oxychlorides have been reported.The structure of BiSr,O,Cl is made up from layers stacked in the sequence Cl/Sr-O/Bi-Sr-O-Cl/ Sr-O/Cl; the Bi-Sr-0-C1 is unusual among bismuth oxyhalides in having both oxide and halide in the same layer. The analogous BiCa,O,Cl is also reported.,' A new '' V. A. Carlson and A. M. Stacy J. Solid State Chrm. 1992 96 332. M. A. Subrarnanian A. K. Ganguli and A. W. Sleight Mat. Res. Bull. 1992 27 799. 61 0.Joubert A. Jouanneaux M. Ganne and M. Tourneaux Mat. Res. Bull. 1992 27.154. 62 J. Huang and A. W. Sleight J. Solid State Chrm. 1992 96,154. New Compounds and Structures 8 LI 0 Ba 8 Bi 00 Figure 11 Structure of Li,Ba,Bi,O viewed down b (Reproduced by permission from J. Solid State Chem. 1992 96 332) Sillen-type phase Bil,7Ca2,704-yC14 and the related Bi,,,Ca, ,CuO -,,C1, which contains an additional CuO sheet have been reported., Oxysalts of Sulfur and Selenium.-The crystal structures of K,Co(Se03) and LaHSe,O have been determined.64,65 The diselenite CoSe20 has been found to be isomorphous with ZnSe,O and MnSe,0,.66 The structure of the mixed-valent tantalum oxysulfide La,Ta,S,O has been found to bear resemblance to that of CaTa,O, with a similar packing arrangement of TaO bi-octahedra; alternating short and long Ta-Ta distances indicate some metal-metal bonding Figure 12.67A novel lithium Nasicon-type phase based on sulfate and selenate groups Lix{M(~~)xM(~~~)l-,,(SeO4)?} has been reported.68 -x(so4)3 6 Non-oxide compounds Carbides.-Novel Scandium carbides Sc,TC4 (T = Ru Ru Os Or Ir) with the Sc,CoC structure have been prepared.69 63 W.J. Zhu Y.Z. Huang J.K. Liang and Z.X. Zhao Mat. Res. Bull. 1992. 27. 885. b4 K. Wildner. Acta Crystallogr. Sect. C 1992 48. 410. h5 R. Morris W. T. A. Harrison G. D. Stucky and A. K. Cheetham Acru Crystallogr.,Sect. C 1992,48 1182. 66 W.T. Harrison A.V. P. McManus and A. K. Cheetham Acta Crystallogr. Sect. C 1992 48. 412. " T. D. Brennan and J. A. Ibers J. Solid Srate Chem. 1992. 98 82. bx P.R. Slater and C. Greaves J. Muter. Chem. 1992 2 1267. h9 R.-D. Hoffmann R. Pottgen and W. Jeitschko J. Solid State Chem. 1992 99. 134. 420 J. T.S. Irvine Figure 12 Unit cell ofLa,Ta,S,O uiewed down c (Reproduced by permission from J. Solid State Chem. 1992 98 82) Nitrides.-A series of antiperovskite nitrides Ca,MN (M = P As Bi Ge Sn Pb) have been ~repared;~’ unusually the formal valence of Ge Sn and Pb is + 3. Li,NbN has been found to exhibit an ordered antifluorite-type structure with each octant of the cubic unit cell containing a distorted Li,Nb cube.71 The structure of Ca,VN has been found to be based on sheets of VN anion^.^' Pnictides.-Novel ternary pnictide Zintl phases containing Zi -dumbells Na,M,Z (M = Sr Eu; Z = P As) have been reported.73 Sulfides.-Two new rare-earth sulfides have been reported BaSm,S crystallizes with the CaFe,O structure7 and CaYb,S crystallizes with the Y 3S4 str~cture.,~ LaPbCuS has been found to have a structure closely related to cr-La,S with seven-coordinate La and Pb atoms disordered unequally over two sites and tetrahedral Cu forming corner-sharing chains.76 A new tantalum sulfide with a structure based on TaS chains has been reported., A new lead sulfide related to Robinsonite Pb,Sb,S,, built up from chains of square pyramidal (Pb,Sb)S groups has been ~haracterized.~’ ’O M.Y. Chern D. A. Vennos and F. G. Disalvo J. Solid Stute Chem. 1992. 96 415. ” D. A. Vennos and F. G. Disalvo Acta Crystallogr.,Sect. C 1992 48 610. l2 D. A. Vennos and F.J.Disalvo J. Solid State Chem. 1992 98 318. 73 W. Honle J. Lin M. Hartweg and H.6. von Schnering J. Solid Stute Chrm. 1992. 97 1 l4 J. D. Carpenter and S.-J. Hwu Acru Crystallogr. Sect. C 1992 48 1164. 75 J. D. Carpenter and S.-J. Hwu. J. Sdid Stare Chem. 1992 97 332. l6 T. D. Brennan and J. A. Ihers. J. Solid State Chrm. 1992. 97 377. ” H. Wada M. Onoda and H. Nozaki. J. Solid Stute Chem. 1992 97 29. ” A. Skowron I. D. Brown and R. J. D. Tilley J. Solid State Chew.. 1992 97 199. New Compounds and Structures 421 Three new quaternary sulfides made up of layers of metal-centred tetrahedra separated by potassium ions KGaSnS, KInGeS, and KGaGeS, have been rep~rted.’~ A new misfit layer structure (BiS) ,,,CrS2 made up from rocksalt BiS layers and a CrS layer of edge-sharing CrS octahedra has been reported.80 Cha1cogenides.-Two new selenide misfit layer compounds (BiSe) ,NbSe and (BiSe),,,,TaSe, have also been reported.81 CaYbInSe and its sulfur analogue both with the olivine structure have been reported.82 The zirconium chalcogenides KCuZrQ (Q = S Se Te) have been found to present a layered-type structure8 and the structure of EuZrSe has been found to contain columns of double edge-sharing octahedra linked together by Eu bicapped trigonal prisms.s4 BaNb,,,Se has been found to present the BaVS structure type.85 K3CU3Nb2Se8 and its Ta and S analogues have been found8 to have structures containing one-dimensional triple chains (Cu,Nb,Sei -) and three new compounds with the Eu,,,Nb,Se structure type where Eu has been substituted by Pb Sn and Sr have been reported.87 Two new ternary transition metal tellurides with a layered Cd1,-related structure NbIrTe and TaIrTe, have been reported Figure 13.88A new member of the Nb,MTe, series Nb,GeTe, has been prepared.89 A new layered telluride with an unusual Ta-Fe bonded network TaFe,,,,Te, has been reported.” The structure (Figure 14) can be Figure 13 View of the structure of NbIrTe down a (Reproduced by permission from J.Solid State Chem. 1992 97 366) ’’ P. Wu Y.-J. Lu and J.A. Ibers J. Solid State Chem. 1992 97 383. A. Lafond P. Fragnaud M. Evain and A. Meerschaut Mat. Res. Bull. 1992 27 705. ‘I M.Y. Zhou A. Meetsrna J. L. de Boer and G.A. Wiegers Mat. Res. Bull. 1992 27 563. R2 J.D. Carpenter and S.-J.Hwu Chem. Muter. 1992 4 1368. 83 M.F. Mansuetto P.M. Keane and J. A. Ibers J. Solid State Chem. 1992 101 257. x4 A. Mar and J. A. Ibers Acta Crystallogr. Sect. C 1992 48 771. 85 B.-L. Chen. G. Saghi-Szabo B. Eichorn J.-L. Peng and R. Greene Mat. Res. Bull. 1992 27 1241. 86 Y.-J. Liu and J.A. Ibers J. Solid State Chem. 1992 98 312. *’ T. D. Brennan and J.A. Ibers Mat. Res. Bull. 1992. 27 231. 88 A. Mar and J.A. Ibers J. Solid State Chem. 1992. 97 366. ’’)J. Li and P. J. Carroll Mat. Res. Bull. 1992 27 1073. yo M. E. Badding J. Li F. J. Disalvo. W. Zhou. and P. P. Edwards J. Solid State Chem. 1992 100. 313. 422 J. T.S.Irvine Figure 14 View of the structure ofTaFe,,,,Te down b; dotted circles Ta; hatched circles Fe; partially hatched circles partial Fe occupation; and open circles Te (Reproduced by permission from J.Solid State Chem. 1992 100 313) viewed as a Fe/Ta/Te network sandwiched between tellurium layers. KErTe adopts the a-NaFeO structure an ordered NaCl superstructure.” Halides.-Most of the new non-molecular halide structures reported in 1992 were fluorides. A new tetragonal form of AlF has been reported;92 the layers in this structure are closely related to those in chiolite indeed Na,Ca,Al,F, may be considered as a stuffed polytype. LiInF has been found to present a new structure type consisting of layers of corner-sharing InF octahedra linked by perpendicular chains of LiF edge-sharing octahedra.’ A new layer-type fluoride structure based on layers of Mn3F11 with Mn in an unusual seven-fold coordination interleaved by Na and Ba ions NaBa,Mn,F 1 has been rep~rted.’~ Na,MnF has been found to be essentially isostructural with cryolite A showing only very weak Jahn-Teller di~tortion.~~new cubic perovskite NaBaLiNiF, with Na and Ba disordered over the B-sites has been rep~rted.~ The indium Weberite Na,NiInF has been synthesized and its structure shown to consist of 91 P.M. Keane and J.A. Ibers Acta Crysrullogr.. Sect. C 1992 48 1301. 92 A. Le Bail J. L. Fourquet and U. Bendrup J. Solid Scare Chem. 1992 100 151. 93 P. Gravereau J.P. Charninade T. Gaewdang J. Grannec. M. Pouchard and P. Hagenmuller Acta Crystallogr. Sect. C 1992 48 769. 94 J. Darriet M. Ducau M. Feist A. Tressaud. and P. Hagenmuller J. Solid Stute Chem.1992 98 379. 95 U. Englich W. Massa. and A. Tressaud Acta Crystallogr.. Sect. C 1992. 48. 6. 96 M. Ducau K. S. Suh J. Senegas and J. Darriet. Mat. Res. Bull. 1992 27 11 15. New Compounds and Structures 423 parallel chains of corner-sharing NiF octahedra linked by InF octahedra Figure 15.97The crystal structure of the cobalt Weberite Na,CoAlF is closely related with the CoF chains running parallel in double layers; however between double layers chain directions run at about 60" to each other thus the structure may be considered as intermediate between the orthorhombic Weberite and the trigonal N~M~IA~F,.~~ Figure 15 Perpsective view of Na,NiInF, NiF octahedra ure less heudy shaded than InF octahedra (Reproduced by permission from J.Solid State Chern. 1992 98 121) Two new anion excess Re0,-type structures have been reported PrZr,F ,99 and Pr,Zr,F A number of alkali metal fluoroniobates(Iv) MNb,.,,F, have been prepared;"' these fluoroniobates are isostructural with the alkaline earth hexa- fluoroniobates(rv) ANbF, with 0.25 Nb atoms replacing 0.25 alkali metal atoms which move onto an interstitial site. Both VNbF and VZrF have been found to have a three-dimensional structure built up from corner-sharing Nb/ZrF octahedra related to LiSbF,."* The structure of KYF has been reported to be a fluorite-related superstructure. lo3 New salts of the one-dimensional chain-cation (Ag-F-). AgFBF, AgFAuF, and AgFAuF, have been prepared.lo4 AgFBF has a linear cationic chain but with two slightly different Ag-F interatomic distances.lo4 The crystal structure of Hg,Sb,Br has been solved and can be described as containing (Hg,Sb4)4+ shells and (HgBr,)4 octahedral anions.' O5 ~ A new luminescent oxyfluoride BaNbOF, with a structure closely related to 97 G.Frenzen. W. Massa. D. Babel N. Rucaud. J. Grannec A. Tressaud and P. Hagenmuller. J. Solid State Chem. 1992 98 121. yn P. Gravereau A. Boireau J. M. Dance L. Trut and A. Tressaud. Acra C'rystallogr. Sect. C 1992.48.2108. 99 J. P. Laval and A. Abaouz J. Solid Stare Cheni.. 1992 96,324. 100 J. P. Laval and A. Abaouz J. Solid State Chrm. 1992. 100. 90. 101 D. Bizot J. Chassing L. Legras M. 9. De Bournonville and M. Quarton J. Solid State Chem. 1992,97 150. 102 T. Le Mercier J.Chassaing. D. Bizot. and M. Quarton. Mat. RKS.Bull.. 1992 27 259. 103 Y. Le Fur. K. M. Khaidukov. and S. Aleonard Acta Crystallogr. Sect. C 1992 48 978. 104 W. J. Casteel G. Lucier. R. Hagiwara H. Borrmann and N. Rartlett d. Solid State Chem. 1992. 96 84. 10s A. V. Shevelkov E.V. Dikarev and 9. A. Popovkin. J. Solid State Chem. 1992. 98 133. 424 J. T.S. Irvine KSbF, has been reported.lo6 A new acentric oxyfluoride Ba,TiOF, has been reported.lo7 Its structure is built up from TiO,F octahedra which form kinked chains running along the c axis Figure 16. 0 0 Figure 16 View of the structure of Ba,TiOF showing the trans chains ofTiO,F octahedra (Reproduced by permission from J. Solid State Chem. 1992 99 355) lo6 A.M. Srivasta and J.F. Ackerman Muter. Chem. 1992 4 1011. lo' M. P. Crosnier and J. L. Fourquet J. Solid Stare Chem. 1992 99,355.