bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and Characterization of New Chlorocarbonylrhenium(I) Complexes with P‐Donor Chelate Ligands
Authors: Bolaño Sandra , Bravo Jorge , Castro Jesús , García‐Fontán Soledad , Marín M. Carmen 
Published: January 2010

AbstractChlorocarbonylrhenium(I) complexes fac,cis‐[ReCl(CO)3L1–3][L1 = Ph2PO(CH2)2OPPh2 (1); L2 = Ph2PO(CH2)3OPPh2 (2); L3 = iPr2PO(CH2)2OPiPr2 (3)] were synthesized by reaction of [ReCl(CO)5] with the appropriate diphosphinite ligands L1–3. Reaction of mer,cis‐[ReH(CO)3L2] with HCl affords an isomer of compound 2, the complex mer,cis‐[ReCl(CO)3L2] (4). The new complexes were characterized by IR, 1H, 13C{1H} and 31P{1H} NMR spectroscopy and in the case of complexes 2 and 4 by single‐crystal X‐ray structure determination.
Solvothermal Synthesis, Crystal Structure, and Properties of a New Organic‐Templated Holmium Sulfate with 1D Single Ladder Chains
Authors: Zhou Wanli , Ding Xiaorun , Zhang Zhibin , Zheng Lei , Xu Yan , Zhu Dunru 
Published: January 2010

AbstractA new organic amine templated 1D holmium sulfate (C2H8N)[Ho(SO4)2·H2O] (1) has been synthesized and solvothermally and structurally characterized by single‐crystal X‐ray diffraction, IR spectroscopy, thermogravimetric and X‐ray diffraction analyses as well as scanning electron microscopy (SEM). The structure of framework 1 is constructed from HoO8 polyhedra and SO4 tetrahedra. S(1) and S(2) connects Ho(1) and its crystallographic partners by using three S–O–Ho linkages to generate double chains, whereas the adjacent double chain are connected by μ3‐O (O5) atoms to form a novel single ladder chains.
Der quasibinäre Schnitt La3In5 – La3Pb5: Synthesen, Strukturchemie, Phasenbreiten und chemische Bindung
Authors: Dürr Ines , Röhr Caroline 
Published: January 2010

AbstractThe synthetic, crystallographic, and bond theoretical study of the ternary mixed lanthanum indides/plumbides of the quasibinary section La3In5 – La3Pb5 allows to explore the crystal chemistry of 3:5 polar intermetallic compounds in the electronic region between 24 and 29 valence electrons per formula unit (v.e./f.u.). All compounds of this nearly continuous series exhibiting two different structure types were prepared in pure phase from stoichiometric melts of the elements. The Pu3Pd5 structure type (orthorhombic, space group Cmcm, Z = 4) with slightly distorted nido type square pyramidal (In/Pb)5 clusters is stable from the known binary compound La3In5 (24 v.e./f.u., electron precise clusters In59– after Wade) up to the composition La3In3.8Pb1.2 (25.2 v.e./f.u.) [a = 1049.99(8), b = 838.76(7), c = 1053.74(6) pm, R1 = 0.0528]. The stability range of the second structure type, La3In4Ge (tetragonal, space group I4/mcm, Z = 4), starts at slightly higher lead proportions at the composition La3In3.7Pb1.3 [a = 873.4(2), c = 1214.6(4) pm, R1 = 0.0585]. Several crystals with increasing lead content La3In2.3Pb2.7 [a = 874.32(8), c = 1227.56(8) pm, R1 = 0.0226], La3In1.3Pb3.7 [a = 876.61(6), c = 1226.69(9) pm, R1 = 0.0755], La3InPb4 [a = 878.72(6), c = 1237.44(6) pm, R1 = 0.0339] up to the border composition La3In0.8Pb4.2 [a = 880.05(7), c = 1238.2(1) pm, R1 = 0.0553] have also been characterized by single crystal structure analysis. According to the anionic building blocks of this structure type, isolated [Ge/Pb]4– anions and heavily puckered 4.82 nets of three‐bonded In/Pb atoms (i.e. [In2–(Pb–)3] after Zintl), this border composition exactly fits the Zintl electron count. A final compound of this series, the binary phase La3Pb5 is not known. Simple electron counting rules (Zintl concept, together with Wade’s rules) hold only for the border compounds of the two structure types, La3In5 and La3InPb4. Their validity and the details of the chemical bonding are thus evaluated in an accompanying computational study, where the electronic band structures of the binary compounds La3In5 and La3Sn5 (Pu3Pd5 structure type) and the model system “La3Pb5” (calculated using the crystal data of La3InPb4) are calculated using FP‐LAPW band structure methods.
Description of Anhydrous (Black) Dioptase as a S = 1/2 Uniform Antiferromagnetic Chain System
Authors: Law Joseph M. , Hoch Constantin , Whangbo Myung‐Hwan , Kremer Reinhard K. 
Published: January 2010

AbstractThe structural and magnetic properties of anhydrous (black) dioptase, CuSiO3, were investigated by carrying out single‐crystal X‐ray diffraction, specific heat, and magnetic susceptibility measurements as well as by performing spin dimer analysis based on extended Hückel tight‐binding calculations. Our spin dimer analysis indicates that black dioptase is a S = 1/2 uniform antiferromagnetic chain system with the interchain spin exchange weaker than the intrachain exchange by three orders of magnitude. Specific heat and magnetic susceptibility measurements show that the intrachain exchange is –174(2) K, and the interchain exchange is of the order of ~2 K. They lead to long‐range magnetic ordering at about 5 K as evidenced by a broad anomaly in the specific heat.
Static and Ultrasonic‐assisted Aging Effects on the Synthesis of Analcime Zeolite
Authors: Azizi Seyed Naser , Yousefpour Maryam 
Published: January 2010

AbstractThe synthesis of zeolite ANA under static hydrothermal conditions was performed accompanied by an additional static and ultrasonic‐assisted aging of the reaction mixture prior to crystallization. The aging process was compared with stirring‐assisted aging, microwave‐assisted aging and syntheses without any aging. The influence of aging time on the crystallization time of zeolite ANA was investigated. The static and ultrasonic‐assisted aging can shorten the crystallization time of the ANA phase. Moreover, ultrasonic‐assisted aging leads to altered morphologies of the particles. The products were characterized by X‐ray diffraction (XRD) and scanning electron microscopy (SEM).
The [U2I10]2– Anion: Synthesis and Structure of [Ta7(Se2)14][U2I10]2
Authors: Wells Daniel M. , Ibers James A. 
Published: January 2010

AbstractThe new anion [U2I10]2– has been isolated in the compound [Ta7(Se2)14][U2I10]2. This compound was synthesized from the elements at 1173 K. It crystallizes in space group Cccm of the orthorhombic system with four formula units in a cell of dimensions a = 21.5134(9) Å, b = 22.1619(9) Å, and c = 16.7834(6) Å. The crystal structure comprises infinite [Ta(Se2)2]n cationic chains charge balanced by [U2I10]2– anions. The new [U2I10]2– anion is formed by two edge‐sharing UI6 octahedra. The U–I bond lengths are normal for tetravalent uranium. For charge balance, the [Ta7(Se2)14]4+ cation must contain three TaIV and four TaV atoms. Charge is delocalized over this cation as the Ta···Ta interactions differ minimally.
Zigzag Chains of Alternating Atoms in A2AuBi (A = Na, K) and K2AuSb. Synthesis, Structure, and Bonding
Authors: Kim Sung‐Jin , Miller Gordon J. , Corbett John D. 
Published: January 2010

AbstractThe polar intermetallic phases A2AuBi (A = Na (I), K (II)), and K2AuSb (III) were obtained by direct reaction of the elements at elevated temperatures in niobium ampoules. The three isotypic compounds extend the prominent A2MPn (M = transition metal; Pn = group 15) structure family. Single‐crystal X‐ray diffraction experiments show that these phases (I / II / III) crystallize in the orthorhombic space group Cmcm (No. 63), with a = 9.447(2) / 10.632(2) / 10.450(2) Å; b = 7.700(2) / 7.918(2) / 7.857(2) Å; c = 5.849(1) / 6.597(1) / 6.501(1) Å; V = 425.4(2) / 555.4(2) / 533.8(2) Å3, respectively, and Z = 4. The simple structures, which contain zigzag chains of linear two‐bonded gold atoms and acute angles (64 to 76°) at two‐bonded antimony or bismuth, can readily be rationalized with the Zintl‐Klemm concept. TB‐LMTO calculations show distinct band gaps at EF, and analyses of DOS and COHP curves show optimized Au–Pn bonding, appreciable Au–Au interactions across the chains, and covalent interactions between A and Pn atoms. The observed structural preference over an isoelectronic NaTl type structure, the cation influences, and site coloring were investigated with VASP and EHTB calculations.
Syntheses and Crystal Structures of CsCuNd2Se4 and CsCuGd2Te4: Two Non‐Isotypical Cesium Copper Lanthanide Chalcogenides with {}^1_\infty{[CuCh3]5–} Chains of Vertex‐Shared [CuCh4]7– Tetrahedra
Authors: Babo Jean‐Marie , Strobel Sabine , Schleid Thomas 
Published: January 2010

AbstractThe new chalcogenides CsCuNd2Se4 and CsCuGd2Te4 with analogous formulae were prepared from the elements by a flux method with CsCl as fluxing agent and cesium source. CsCuNd2Se4 crystallizes in the orthorhombic space group Cmcm (no. 63) with four formula units per unit cell (a = 424.69(3), b = 1475.81(8), c = 1465.42(8) pm), whereas CsCuGd2Te4 is monoclinic with the space group C2/m (no. 12) and twelve formula units per unit cell (a = 3764.75(19), b = 436.70(2), c = 2105.37(11) pm, β = 107.423(4)°). Both crystal structures feature three‐dimensional arrangements of the lanthanide and coinage metal cations along with the chalcogenide anions according to {}^3_\infty{[CuLn2Ch4]–} (Ln = Nd or Gd, Ch = Se or Te), leaving channels behind, in which the Cs+ cations are incorporated. Hereby, vertex‐linked [CuCh4]7– tetrahedra join to form {}^1_\infty{[CuCh3]5–} chains in both cases. Whereas for the CsCuNd2Se4 structure, these chains ({}^1_\infty{[CuSe3]5–}) are embedded into a three‐dimensional network, erected by edge‐ and vertex‐linked [NdSe6]9– octahedra, which form corrugated layers further connected by common edges, in CsCuGd2Te4 a different three‐dimensional {}^3_\infty{[Gd2Te4]2–} framework arises, comprising {}^1_\infty{[CuTe3]5–} chains, as well as vertex‐ and edge‐linked [GdTe6]9– octahedra. The major difference of the structures originates from the channels, in which the Cs+ cations are located. In the tunnels of CsCuNd2Se4, the Cs+ cations exhibit a bicapped trigonal prismatic selenide coordination, whereas in CsCuGd2Te4 with two Cs+ cations in one channel, they show bicapped trigonal prisms, as well as monocapped cubes of telluride anions as coordination spheres.
Analysis of Electronic Structures and Chemical Bonding of Metal‐rich Compounds. 2. Presence of Dimer (T–T)4– and Isolated T2– Anions in the Polar Intermetallic Cr5B3‐Type Compounds AE5T3 (AE = Ca, Sr; T = Au, Ag, Hg, Cd, Zn)
Authors: Lee Changhoon , Whangbo Myung‐Hwan , Köhler Jürgen 
Published: January 2010

AbstractFirst principles density functional calculations were carried out to probe the oxidation states of the transition‐metal and alkaline‐earth elements in the Cr5B3‐type compounds AE5T3 consisting of T2 dimers and isolated T atoms (i.e., Ca5Au3, Ca5Ag3, Ca5Hg3, Sr5Cd3, and Ca5Zn3). The electronic structures of all these AE5T3 compounds are best described as [(AE2+)5(T–T)4–(T2–)]+4e–. In the covalent bonding of the AE2+ ions with the transition metal anions T2–, the (n–1)d orbitals of AE2+ contribute more than the ns and np orbitals of AE2+.
NaSc[BP2O6(OH)3][(HO)PO3]: Synthesis and Crystal Structure of an Alkali‐Metal Scandium Borophosphate Hydrogenphosphate
Authors: Menezes Prashanth W. , Hoffmann Stefan , Prots Yurii , Kniep Rüdiger 
Published: January 2010

AbstractThe compound NaSc[BP2O6(OH)3][(HO)PO3] was prepared under mild hydrothermal conditions. The crystal structure was determined from single crystal X‐ray data: monoclinic, space group P21/c (No. 14), a = 5.0010(1) Å, b = 12.4271(9) Å, c = 15.8340(14) Å, β = 94.201(4), V = 981.41(11) Å3 and Z = 2. The crystal structure comprises of isolated borophosphate oligomers, [BP2O6(OH)3]2–, and isolated hydrogenphosphate groups, [(HO)PO3]2–, which are interconnected by ScO6 coordination octahedra by sharing common corners. The resulting three‐dimensional framework is characterized by channels running along [100] forming four‐, six‐, and twelve‐membered rings. Sodium ions reside within the six‐membered ring channels.
Tri‐ and Tetracoordinate Copper(I) Complexes of 1,1′‐Diisocyanoferrocene
Authors: Siemeling Ulrich , Klapp Lutz R. R. , Bruhn Clemens 
Published: January 2010

AbstractTwo homoleptic copper(I) complexes of the bidentate isocyanide 1,1′‐diisocyanoferrocene (1) were prepared and structurally characterised. The dications present in [Cu2(μ‐1)3][PF6]2 exhibit a paddle‐wheel‐like structure with trigonal‐planar CuI. These dications are connected in a chain‐like fashion by bridging ligands 1 in the coordination polymer [{Cu2(μ‐1)3}(μ‐1)]n(OTf)2n, which contains tetracoordinate CuI in a distorted tetrahedral coordination environment. The hexafluorophosphate analogue of the latter compound was also prepared.
$^3_\infty$[Tl2Zn(ADC)2(H2O)2]: the First Coordination Polymer with Acetylenedicarboxylate (ADC2–) as Bridging Ligand containing two Different Metal Ions
Authors: Ahlers Ruth , Ruschewitz Uwe 
Published: January 2010

AbstractFrom an aqueous solution containing ZnCO3, Tl(CH3COO), and acetylenedicarboxylic acid (H2ADC: HOOC‐C≡C‐COOH) single crystals of $^3_\infty$[Tl2Zn(ADC)2(H2O)2] (1) were obtained. Compound 1 crystallizes in triclinic space group P$\bar{1}$ with Z = 1. A slightly distorted octahedral ZnO6 coordination and a very unsymmetric TlO6 coordination (Tl–O < 321 pm) are found, the latter probably caused by a stereochemically active lone pair at Tl+. These polyhedra are connected by the ADC2– linker to form a 3D network structure. Additionally, hydrogen bonds are formed, which involve the water molecules (O···O starting at 274 pm). These are only coordinated to Zn2+. Compound 1 is the first coordination polymer of ADC2–, which contains two different metal ions.
Synthesis and Structural Studies on Tetranuclear Tin Compositions Containing Tin {[R2Sn(LH)]2O}2 Moieties (R = Bu or Oct and LH = 4‐[((E)‐1‐{2‐Hydroxy‐5‐[(E)‐2‐(aryl)‐1‐diazenyl]phenyl}methylidene)‐ amino]benzoate)
Authors: Basu Baul Tushar S. , Das Pradip , Song Xueqing , Eng George , Quah Ching Kheng , Fun Hoong‐Kun 
Published: January 2010

AbstractDiorganotin compounds containing tetranuclear tin compositions of the type {[R2Sn(LH)]2O}2 in which LH is deprotonated carboxylic acid LHH′ (H′ are the carboxylic and H the phenolic protons of the benzoic acid) HO2C–C6H4‐4‐{N=C(H)C6H3‐2‐OH‐5‐(N=N–C6H4X)} (X = H for L1H, X = 2‐CH3 for L2H, X = 3‐CH3 for L3H, and X = 4‐CH3 for L4H; R = Bu or Oct), were synthesized and characterized by FT‐IR, NMR, and 119Sn Mössbauer spectroscopy. One of the complexes, {[Oct2Sn(O2CC6H4{N=C(H)C6H3‐2‐OH‐5‐(N=NC6H4CH3‐2)})]2O}2 was characterized by single‐crystal X‐ray diffaraction, which revealed that the compound is a centrosymmetric tetranuclear bis(dicarboxylatotetrabutyldistannoxane) complex with a planar Sn4O2 core. The two μ3‐oxo oyxgen atoms are connected to a Sn2O2 ring and to two exocyclic tin atoms. The four carboxylate ligands display two different modes of coordination. Both modes of coordination involve bridging two structurally distinct tin atoms. The solution structures of the complexes were unravelled by 119Sn NMR spectroscopy, and found to be identical to those of the crystalline state.
Carbon Dioxide Fixation with Dialkyltellurium(IV) Dihydroxides
Authors: Beckmann Jens , Bolsinger Jens , Duthie Andrew 
Published: January 2010

AbstractAqueous solutions of Me2Te(OH)2 and (CH2)4Te(OH)2 readily absorb carbon dioxide giving rise to the formation of the dialkyltelluroxane carbonates (Me2TeOTeMe2CO3)n (1) and HO(CH2)4TeOTe(CH2)4CO3Te(CH2)4OH·2H2O (2·2H2O), which were characterised by 13C MAS and 125Te MAS NMR spectroscopy as well as X‐ray crystallography. The spatial arrangement of the tellurium atoms is defined by C2O2 donor sets in the primary coordination sphere and one or two secondary Te···O contacts, which involve coordination of the carbonate moieties. In turn, the different Te–O coordination modes render a lack of symmetry to the carbonate moieties, which show significantly different C–O bond lengths, an important feature when contemplating the C–O bond activation in carbonates. The structural and spectroscopic parameters of 1 and 2 are discussed in comparison with other heavy p‐block element carbonates. In solution, electrolytic dissociation of 1 and 2 takes place.
Syntheses, Structures, and Photoluminescent and Magnetic Properties of Four Novel Complexes Constructed from 2,4,5‐Tri(4‐pyridyl)‐imidazole and Benzene‐1,3,5‐tricarboxylic Acid
Authors: Wang Li , Gu Wen , Deng Jun‐Xiu , Liu Mei‐Ling , Xu Na , Liu Xin 
Published: January 2010

AbstractFour novel 2D complexes M2(Hptim)2(HBTC)2 [M = Co (1), Cd (2), Zn (3), Mn (4); Hptim = 2,4,5‐tri(4‐pyridyl)‐imidazole; HBTC2– = Benzene‐1,3,5‐tricarboxylic acid] were synthesized under solvothermal conditions. The four complexes are isomorphous and present a unique structure with a 1D ladder of [Co2(HBTC)2]n. The 2D network structure of 1 is achieved through bridging Hptim groups, which coordinate to the metal atoms of two adjacent 1D [Co2(HBTC)2]n ladders. Magnetic measurements reveal that dominant antiferromagnetic coupling was observed in compounds 1 and 4. Compounds 2 and 3 both exhibit strong fluorescent emissions in the solid state and may be suitable candidates for fluorescent materials.
The New Binary Tungsten Iodide W15I47
Authors: Ströbele Markus , Meyer H.‐Jürgen 
Published: January 2010

AbstractThe new tungsten iodide W15I47 was synthesized by reacting tungsten hexacarbonyl with iodine under elevated pressure and temperature conditions. The structure of W15I47 was refined by single‐crystal X‐ray diffraction with the non‐centrosymmetric space group C2 [Z = 2, a = 4088.3(4) pm, b = 952.3(1) pm, c = 1198.5(2) pm, and β = 103.97(1)°]. The characteristic motif in the structure is the square pyramidal tungsten cluster that may be constructed from an octahedral [(W6I8i)I6a]2– cluster by removing one tungsten atom together with its outer iodide ligand to yield [(W5I8i)I5a]n–. The formula W15I47 represents three square pyramidal tungsten clusters with two of them being distinguishable in [(W5I8i)Ia(I3)2a(I3)2/2a–a][(W5I8i)I2a(I3)3/2a–a]2, by different numbers of iodide and tri‐iodide ligands at the cluster vertices.
Two Coordination Polymers Constructed from Pillared M–O (M = Na+ or Ba2+) Subunits with 3‐Formyl‐4‐hydroxybenzenesulfonic Acid as Ligand
Authors: Li Shu‐Ni , Zhai Quan‐Guo , Hu Man‐Cheng , Jiang Yu‐Cheng 
Published: January 2010

AbstractTwo new coordination polymers, [Na(H2L)(H2O)2]n (1) and [Ba(H2L)2(H2O)]n (2) (H3L = 3‐formyl‐4‐hydroxybenzenesulfonic acid) were synthesized and structurally characterized. The H2L– ligand shows three different bridging modes, μ3 in 1, μ3 and μ4 in 2. Compound 1 presents a 2D pillared structure, whereas 2 forms a 3D framework. Both 1 and 2 show blue luminescence at 380 nm in aqueous solution, however, their solid state emissions are at 406 and 446 nm, respectively.
Assembly of a Novel Dumbbell‐type Dinuclear Copper(II) Complex: Synthesis, Structure and Properties
Authors: Sun Wen Wu , Li Shi Rong , Zhou Hong , Pan Zhi Quan , Huang Qi Mao , Hu Xue Lei 
Published: January 2010

AbstractA new dumbbell‐type 4,4′‐bipy‐bridged dinuclear copper(II) complex, [Cu2(4,4′‐bipy)L2(H2O)2](ClO4)4·8CH3OH·10H2O, where L = 1‐[bis(3‐aminopropyl)amino]‐2‐ propanol and bipy = bipyridine, has been synthesized and characterized, X‐ray crystallographic analysis shows that the [Cu2(4,4′‐bipy)L2(H2O)2]4+ cations and water molecules generate layer structures extending parallel to bc planes through hydrogen bonding interactions of O–H···O and C–H···O. The layers are also connected by hydrogen bonding interactions involving methanol, water, and perchlorate anions. These interactions lead to the formation of rectangular channels of 12.3 Å × 6.0 Å along the crystallographic c axis. Perchlorate anions fill in each channel in a sandwich‐like packing mode, they are joined with the adjacent layers by water heptamers. Magnetic susceptibility measurements show that the magnetic exchange interaction is weak although it has a regular π‐type electron transfer pathway. Furthermore, the electrochemical and thermogravimetric properties of the complex were also investigated.
Structure and Magnetic Properties of Two Lanthanide 1,4‐Phenylenediacetate Compounds
Authors: Chen Zilu , Xiong Wei , Zhang Zhong , Liang Fupei 
Published: January 2010

AbstractThe reactions of Ln(NO3)3 with 1,4‐phenylenediacetic acid (H2PDA) under hydrothermal conditions produced two isostructural lanthanide coordination polymers with the empirical formula [Ln2(PDA)3(H2O)]·2H2O [Ln = Nd (1), Sm (2)]. Single‐crystal X‐ray diffraction analyses revealed that both contain one‐dimensionalmetal carboxylato chains, which are further connected by the–CH2C6H4CH2– spacers of PDA2– ligands to yield a three‐dimensional metal‐organic framework. Magnetic susceptibilities of 1 and 2 were measured. The experimental χmT value of both compounds decreases continuously with decreasing temperature over the whole temperature range. The best least‐squares fit of the experimental data of 1 to a theoretical equation in the temperature range of 70–300 K gives the zero‐field splitting parameter Δ = 2.21 cm–1 and the magnetic interaction between the NdIII ions 2zJ′ = –1.97 cm–1, which indicates the presence of antiferromagnetic interaction between the NdIII ions. The experimental χmT value of 2 at 2 K is much smaller than the expected value for two free SmIII ions (6H5/2, g = 2/7) in the ground state, indicating that an antiferromagnetic interaction possibly exists between SmIII ions at low temperature. Fitting the magnetic data of 2 above 110 K based on an equation deduced from the SmIII ion in a monomeric system with free‐ion approximation gave a spin‐orbit coupling parameter λ = 192(2) cm–1
GeSb4Te4 – a New 9P‐Type Phase in the System Ge/Sb/Te
Authors: Schneider Matthias N. , Oeckler Oliver 
Published: January 2010

Abstract9P‐GeSb4Te4 is a new germanium antimony telluride that can be obtained from the elements as a homogeneous phase by quenching a stoichiometric melt and subsequently annealing the sample at 500 °C. The crystal structure consists of alternating antimony layers similar to those in elemental antimony and rocksalt‐type blocks similar to those in GeSb2Te4. Although not thermodynamically stable according to the phase diagram, GeSb4Te4 is remarkably stable up to 540 °C, where it starts to melt incongruently according to DSC and DTA measurements. The crystal structure has been refined from single‐crystalX‐ray data [P$\bar{3}$m1, a = 4.2466(2) Å, c = 17.483 Å, R1 = 0.0355]. Its diffraction patterns are very similar to those of other 9P‐type tellurides like Ge2Sb2Te5 and Sb2Te, which tend to occur as very pronounced false minima in structure refinements. The electrical conductivity is low (33 S·cm–1) but exhibits metallic temperature dependence.
The Structural Anomaly of Zinc: Evolution of Lattice Constants and Parameters of Thermal Motion in the Temperature Range of 40 to 500 K
Authors: Nuss Jürgen , Wedig Ulrich , Kirfel Armin , Jansen Martin 
Published: January 2010

AbstractThe crystal structure of elemental zinc deviates from the ideal hexagonal close packing by a significantly increased c/a ratio. We determined the evolution of the lattice constants and thermal displacement parameters in the temperature range of 40 to 500 K by accurate single‐crystal X‐ray diffraction. The c axis varies linearly within the whole temperature range, whereas the a lattice constant stays constant below ≈︁ 160 K, which indicates that at lower temperatures the Zn–Zn distances are no longer thermally contractible in the ab plane. As a further significant observation, the thermal expansion coefficient along the c direction exceeds the one in a direction by a factor of ~10, and consequently the c/a ratio slightly reduces, but stays unusually high (c/a = 1.826, extrapolated for T = 0 K). The thermal motion of zinc shows a striking anisotropy as expressed by a ratio U33/U11 of ≈︁ 2.6 at 500 K. This ratio decreases significantly towards lower temperatures and reaches almost 1.6 at 40 K. The thermal behavior as observed is thus reflecting the structural and bonding anisotropy of zinc at ambient conditions, but thermal motion turns isotropic at cooling, in contrast to the atomic equilibrium structure.