Crystal structures of phosphomolybdyl salts: Pb(MoO2)2(PO4)2 and Ba(MoO2)2(PO4)2

Crystal structures of Pb(MoO₂)₂(PO₄)₂ and Ba(MoO₂)₂(PO₄)₂ were determined. Both compounds contain the molybdyl group MoO₂. The monoclinic unit-cell parameters are a = 6.353(7), b = 12.289(4), c = 11.800 Å, β = 92°56(6), and Z = 4 for the lead salt and a = 6.383(8), b = 7.142(7), c = 9.953(8) Å, β = 95°46(8), and Z = 2 for the barium salt. $\text{P2}{}_1\text{c}$ is the common space group. The R values are respectively R = 0.027 and R = 0.031 for 1964 and 1714 independent reflections. The frameworks built up by a three-dimensional network of monophosphate PO₄ and molybdyl MoO₂ groups are similar, characterized mainly by corner-sharing PO₄ and MoO₆ polyhedra. Two oxygen atoms of each MoO₆ group are bonded to the molybdenum atom only as in other molybdyl salts.     

Crystal structures and phase transitions of SrZr(PO4)2-BaZr(PO4)2 solid solutions

A complete series of solid solutions was prepared in the SrZr(PO₄)₂-BaZr(PO₄)₂ system and examined by conventional X-ray powder diffraction (XRPD). The crystals of Sr_xBa_1−xZr(PO₄)₂ with x?0.1 were isomorphous with yavapaiite (KFe(SO₄)₂, space group C2/m). The solid solution with 0.2?x?0.7 has been composed of a new phase, showing a superstructure along the a-axis (c-axis of the yavapaiite substructure). The crystals with 0.8?x?0.9 were composed of both the new phase and the triclinic phase, the latter being isostructural with SrZr(PO₄)₂ (x=1). The crystal structure of the new phase has been determined using direct methods, and it has been further refined by the Rietveld method. The crystal of Sr_0.7Ba_0.3Zr(PO₄)₂ (x=0.7) is monoclinic (space group P2/c, Z=4 and D_x/Mg m⁻³=3.73) with a=1.53370(8) nm, b=0.52991(3) nm, c=0.84132(4) nm, β=92.278(1)° and V=0.68321(6) nm³. Final reliability indices are R_wp=7.32%, R_p=5.60% and R_B=3.22%. The powder specimen was also examined by high-temperature XRPD and differential thermal analysis (DTA) to reveal the occurrence of two phase transitions during heating; the space group changed from P2/c to C2/m at ∼400 K, followed by the monoclinic-to-hexagonal (or trigonal) transition at 1060 K. The P2/c-to-C2/m transition has been, for the first time, described in the yavapaiite-type compounds.     

Structure cristalline de Cu4(PO4)2O

Cu₄(PO₄)₂O is a new copper-rich phosphate. The preparation is described. The unit cell is triclinic, $\text{P}\text{1}$, with a = 7.528 Å, b = 8.090 Å, c = 6.272 Å; α = 113.68°, β = 81.56°, γ = 105.77°. The structure was solved from 1526 independent reflections using Patterson and Fourier syntheses. The final R value is 0.041 for the 1217 strongest reflections. Copper sites form a three-dimensional framework. The structure consists of homogeneous layers of copper and oxygen atoms parallel to the (012) plane. Phosphorus atoms are inserted between copper and oxygen layers.     

NASICON型Na4FeV(PO4)3的合成、晶体结构和电化学性能

采用高温熔盐法制备了NASICON型Na_4Fe V(PO_4)_3单晶。单晶X射线衍射数据分析表明,Na_4Fe V(PO_4)_3属于六方R3c空间群,单胞参数为a=b=0.878 17(4) nm,c=2.170 1(2) nm,Z=6,V=1.449 31(18) nm~3。该磷酸盐属于典型的NASICON结构,由PO_4四面体和Fe/VO_6八面体共顶点组成三维框架结构,提供多维的Na~+传输通道,2种不同类型Na~+位于框架的间隙。以Na_4Fe V(PO_4)_3/C粉末样品作为钠电池正极材料并以金属钠为对电极制备电池时,电化学测试结果表明其具有较高的容量。     

Structure and thermal expansion of LiGe2(PO4)3

LiGe₂(PO₄)₃ belongs to the Nasicon-type family. Room-temperature structure has been determined on a single crystal from 3D X-ray data. Thermal evolution of this structure has been established from neutron powder diffraction data between 300 and 1000 K using the Rietveld method. The thermal expansion is positive along the c-axis, whereas shrinking is observed along the a-axis below 900 K, followed by dilatation. The atomic displacements noted with increasing temperature are consistent with a model proposed for NaZr₂(PO₄)₃.     

Crystal structure of cerium(III) diammonium polyphosphate (NH4)2Ce(PO3)5

Cerium(III) diammonium polyphosphate, (NH₄)₂Ce(PO₃)₅, is triclinic P1 with the following unit cell dimensions: a = 7.241(5) Å, b = 13.314(8) Å, c = 7.241(5)Å, α = 90.35(5)°, β′ = 107.50(5)°, γ = 90.28(5)°, and Z = 2, V = 665.7 ų, D_x = 2.85 g/cm³. The crystal structure of this new type of polyphosphate has been solved and refined from 4130 independent reflections to a final R value 0.029. The most interesting feature of this salt is the existence of two infinite crystallographically nonequivalent (PO₃)^?_∞ chains, one running parallel to the a axis, the other along the c axis, both with a period of five tetrahedra. This compound seems to be the first example of a long chain polyphosphate with crystallographic independent chains.     

Crystal Structure of Ternary Molybdate Rb5FeHf(MoO4)6 — a New Phase in the Rb2MoO4-Fe2(MoO4)3-Hf(MoO4)2 System

Physicochemical analysis (XRPA, DTA) was used to study phase equilibria in a ternary salt system Rb₂MoO₄-Fe₂(MoO₄)₃-Hf(MoO₄)₂ in the subsolidus region. Ternary molybdates with compositions 5:1:3, 5:1:2, and 1:1:1 have been found and synthesized. Crystal and thermal characteristics have been determined. Single crystals of the ternary molybdate Rb₅FeHf(MoO₄)₆ with a composition of 5:1:2 were grown. The crystal structure of the compound was solved using X-ray diffractometry (CAD-4 automatic diffractometer, MoK _α radiation, 1766 F(hkl), R = 0.0298). Hexagonal crystals with unit cell dimensions: a = b = 10.124(1) Å, c =15.135(3) Å, V = 1343.4(4) ų, Z = 2, ρ_calc = 4.008 g/cm³, space group P6₃. The mixed three-dimensional framework of the structure is formed from two sorts of MoO₄ tetrahedra and Fe and Hf octahedra linked through their common O-vertices. Rubidium atoms of three varieties occupy the large voids of the framework.Original Russian Text Copyright © 2004 by B. G. Bazarov, R. F. Klevtsova, A. D. Tsyrendorzhieva, L. A. Glinaskaya, and Zh. G. Bazarova__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 6, pp. 1038–1043, November–December, 2004.     

A new three-dimensional cobalt phosphate: Co5(OH2)4(HPO4)2(PO4)2

A three-dimensional (3D) cobalt phosphate: Co₅(OH₂)₄(HPO₄)₂(PO₄)₂ (1), has been synthesized by hydrothermal reaction and characterized by single-crystal X-ray diffraction, thermogravimetric analysis, and magnetic techniques. The title compound is a template free cobalt phosphate. Compound 1 exhibits a complex net architecture based on edge- and corner-sharing of CoO₆ and PO₄ polyhedra. The magnetic susceptibility measurements indicated that the title compound obeys Curie-Weiss behavior down to a temperature of 17 K at which an antiferromagnetic phase transition occurs.     

Crystal structure and phase transitions of strontium zirconium diorthophosphate, SrZr(PO4)2

The crystal structure of SrZr(PO₄)₂ at 298 K was determined from conventional X-ray powder diffraction data using direct methods, and it was further refined by the Rietveld method. The structure was triclinic (space group , Z=2) with a=0.77508(4) nm, b=0.78887(5) nm, c=0.51251(3) nm, α=95.754(3)°, β=90.228(2)°, γ=92.474(2)°, and V=0.31149(3) nm³. Final reliability indices were R_wp=8.51%, R_p=6.07%, and R_B=2.46%. The powder specimens were also examined by high-temperature XRD and differential thermal analysis to reveal the occurrence of phase transitions from triclinic to monoclinic at 405 K, then to hexagonal (or trigonal) at 1196 K during heating. Upon cooling, the reverse change of the latter transition occurred at 1175 K. The subsequent monoclinic-to-triclinic transition was martensitic and incomplete during further cooling to 298 K. The monoclinic phase is most probably isostructural with yavapaiite. The present paper has described, for the first time, the higher- and lower-temperature polymorphs of the yavapaiite-type structure.     

The crystal structure of Cu4(PO4)2O

Cu₄(PO₄)₂O crystallizes in the space group $\text{P}\text{1}$ with a = 7.5393(8) Å, b = 8.1021(9) Å, c = 6.2764(8) Å, α = 113.65(1)°, β = 98.42(1)° and γ = 74.19(1)°. The structure was refined by full-matrix least-squares techniques using automatic diffractometer data to R = 0.046 (R_w = 0.056). Four unique copper atoms are in six, five-, and four-coordinated polyhedra which are linked together to form a three-dimensional network. The structure is best described in terms of a cubic close-packed array of oxygen atoms with one-tenth of the possible anion sites vacant.     

Topotactic insertion of lithium in the layered structure Li4VO(PO4)2: The tunnel structure Li5VO(PO4)2

A new V(III) lithium phosphate Li₅VO(PO₄)₂ has been synthesized by electrochemical insertion of lithium into Li₄VO(PO₄)₂. This phase, which crystallizes in the space group I4/mcm, exhibits a tunnel structure closely related to the layered structure of Li₄VO(PO₄)₂ and to the tunnel structure of VO(H₂PO₄)₂. The topotactic reactions that take place during lithium exchange and intercalation, starting from VO(H₂PO₄)₂ and going to the final phase Li₅VO(PO₄)₂ are explained on the basis of the flexible coordinations of V⁴⁺ and V³⁺ species. The electrochemical and magnetic properties of this new phase are also presented and explained on the basis of the structure dimensionality.     

A Mixed-Valent Molybdenotungsten Monophosphate with a Tunnel Structure: Nax(Mo, W)2O3(PO4)2

A mixed-valent molybdenotungstophosphate, Na_x(Mo, W)₂O₃(PO₄)₂ (x 0.75) has been isolated for the first time. It crystallizes in the space group P 2₁/m with a = 7.200(1) Å, b = 6.369(1) Å, c = 9.123(1) Å, and β = 106.29(1)°. Its structure consists of M₂PO₁₃ units built up of two M O₆ octahedra (M = Mo, W) and one PO₄ tetrahedron sharing their apices as already observed in several molybdenum phosphates. These units share their apices with PO₄ tetrahedra forming [M₂P₂O₁₅]_∞ chains running along . The host lattice [(Mo, W)₂P₂O₁₁]_∞ can be described by the assemblage of such chains or by the assemblage of [MPO₈]_∞ chains running along , in which one PO₄ tetrahedron alternates with one MO₆ octahedron. The tridimensional framework [Mo, WP₂O₁₁]_∞ delimits tunnels running along , occupied by sodium with two kinds of coordination, 6 and 5. The distribution of the different species, in the octahedral sites according to the formulation Na_0.75(Mo^VI_0.42W^VI_0.58)_M1 (Mo^V_0.75W^VI_0.25)₂O₃(PO₄)₂, is discussed.     

[Cu(TO)2(H2O)4](PA)2的合成和晶体结构

[Cu(TO)₂(H₂O)₄](PA)₂ was prepared by mixing the aqueous solution of 1,2,4-triazol-5-one(TO) and Cu(PA)₂. The molecular structure and crystal structure of the title complex was determined by X-ray single crystal diffraction method. The crystal is triclinic, space group with a=0.7321(1)nm,b=0.7474(2)nm,c=1.3649(3)nm;α=88.65(2)°,β=85.63(1)°,γ=63.35(1)°;V=0.6655(2)nm³,Z=1. The Cu²⁺ coordinated with two TO molecule through its 2-nitrogen atom and four water molecules and showed an octahedral configuration.     

Substitution in barium-fluoride apatite: The crystal structures of Ba10(PO4)6F2, Ba6La2Na2(PO4)6F2 and Ba4Nd3Na3(PO4)6F2

The crystal structures of the apatites Ba₁₀(PO₄)₆F₂(I), Ba₆La₂Na₂(PO₄)₆F₂(II) and Ba₄Nd₃Na₃(PO₄)₆F₂ (III) have been determined by single-crystal X-ray diffraction. All three compounds crystallize in a hexagonal apatite-like structure. The unit cells and space groups are: I, a = 10.153(2), c = 7.733(1)Å, $\text{P6}{}_3\text{m}\text{; a = 9.9392(4), c = 7.4419(5)}$Å, $\text{P}\text{6}$; III, a = 9.786(2), c = 7.281(1)Å, $\text{P}\text{3}$. The structures were refined by normal full-matrix crystallographic least squares techniques. The final values of the refinement indicators R_w and R are: I, R_w = 0.026, R = 0.027, 613 observed reflections; II, R_w = 0.081, R = 0.074, 579 observed reflections; III, R_w = 0.062, R = 0.044, 1262 observed reflections.In I, the Ba(1) atoms located in columns on threefold axes, are coordinated to nine oxygen atoms; the Ba(2) sites form triangles about the F site and are coordinated to six oxygen atoms and one fluoride ion. The fluoride ions are statistically displaced ～0.25 Å from the Ba(2) triangles. This displacement of the F ions is analogous to the displacement of OH ion in Ca₁₀(PO₄)₆(OH)₂.The structures of II and III contain disordered cations. In II there is disorder between La and Na in the column cation sites as well as triangle sites. In III, Nd and Na ions are ordered in the column sites, but there is disorder among Ba and the remaining Nd and Na ions in the triangle sites to give an average site population of $\text{2}\text{3}\text{Ba}\text{,}\text{1}\text{6}\text{Nd}\text{,}\text{1}\text{6}\text{Na}$. The coordination of the rare earth ions and Na ions in the ordered column sites are nine and six oxygens, respectively, in accord with the greater charge of the rare earth ions as compared with Na. The F ions in both II and III suffer from considerable disorder in position, and their locations are not precisely known.     

二维网状配合物[Co(dimb)2(MeOH)2](ClO4)2的合成及晶体结构

设计并合成了一个含咪唑基团的柔性双齿配体:1,3-二(咪唑基-1′-甲基)-5-甲基苯(dimb)(1),并进行了 ¹H NMR和结构表征。通过dimb与高氯酸钴的反应,得到了一个新型的具有二维网状结构的配合物:[Co(dimb)₂(MeOH)₂](ClO₄)₂(2)。X-射线晶体结构测定表明,这两个化合物的晶体学参数分别为:配体(1)属单斜晶系, 空间群     

Crystal structure and cation transport properties of the layered monodiphosphates Rb6Bi4(PO4)2(P2O7)3

Single crystals of the new Bi(III) phosphates, Rb₆Bi₄(PO₄)₂(P₂O₇)₃, have been isolated and their structure has been determined by X-ray diffraction techniques. This compound crystallizes in the monoclinic space group P2₁/c with a=9.077(1)Å, b=9.268(2)Å, c=36.418(6)Å, β=95.75(1)° and Z=8. The crystal structure is made up of BiO₅ and BiO₆ polyhedra sharing the corners with PO₄ tetrahedra and P₂O₇ diphosphate groups. The structure can be described as infinite anionic layers with composition [Bi₄(PO₄)₂(P₂O₇)₃]_∞⁶⁻ parallel to the [301] plane, connected via P-O-Bi bridges to form a three-dimensional open framework. This framework delimits tunnels running along [100] and [010] directions, where the rubidium ions reside. This compound exhibits a rubidium ion conduction but with rather low conductivity value at 640 K.     

一个新的双核锌配合物Zn2(dhaash)2(py)4的合成及晶体结构

The crystal of binuclear zinc complex Zn₂(dhaash)₂(py)₄ was obtained in DMF and pyridine, where H₂dhaash is 2,4-dihydroxy-5-acetylacetophenone-N-salicylhydrazone. It has been characterized by IR, UV, element analysis and X-ray single crystal diffraction. The crystallographic data were as follows: monoclinic system, space group P2₁/c, a=1.108 98(11) nm, b=1.640 84(16) nm, c=1.445 14(14) nm, β=108.617(2)°, Z=2, V=2.492 1(4) nm³, D_c=1.466 g·cm^-3, M_r=1 099.74, μ=1.031 mm^-1, F(000)=1 136 and the final R=0.044 8 and wR=0.105 8 for 4 143 observed reflections with I≥2σ(I), respectively. The X-ray crystal structure analysis revealed that, in the centrosymmetric binuclear complex molecule, two zinc(Ⅱ) centers are linked by two oxygen atoms (O(3) and O(3A)), respectively. Zn(1)…Zn(1A) distance is 0.314 81(6) nm, O(3)…O(3A) distance is 0.270 4(2) nm. Every zinc(Ⅱ) ion has an elongated octahedral coordination. For example, the two pyridine nitrogen atoms, one oxygen atom and one nitrogen atom from salicylhydrazone, one oxygen atom from 2,4-dihydroxy-5-acetylacetophenone in one dhaash^2- ligand and one oxygen atom from 2,4-dihydroxy-5-acetylacetophenone in another dhaash^2- ligand coordinated to zinc(Ⅱ) ion, respectively. Two zinc(Ⅱ) ions and all the 72 non-hydrogen atoms in the two dhaash^2- ligands are in the same plane. CCDC: 261929.     

新配合物[Cd(H2O)2(phen)2](PA)2的制备及晶体结构

The new compound was prepared by the reaction of Cd(ClO₄)₂·6H₂O,1,10-phenanthroline (phen)and picric acid (HPA)(ratio 1∶3∶2) in methanol-aqueous solution refluxing for 4 hours. The crystals used for X-ray analysis was obtained by slow evaporation of the solution at room temperature. The crystal compound is in triclinic with space group with a=1.1363(4)nm,b=1.2593(2)nm,c=1.3972(4)nm,α=93.97(2)?,β=100.84(3)?,γ=106.29(2)?,Z=2,V=1.8690(9)nm³,D_c=1.715g·cm^-3, μ(MoKα)=0.677mm^-1,F(000)=972,R=0.0907,wR=0.2240. In the complex, the Cd(Ⅱ) cation is octahedrally coordinated to two 1,10-phenanthroline ligands and two water molecules in cis disposition. As outer sphere, picrate anions are combined with inner by hydrogen bond and static electricity interaction.     

Hydrothermal Syntheses, Structures, and Properties of Two New Potassium Vanadium Phosphates: K3(VO) (V2O3) (PO4)2(HPO4) and K3 (VO) (HV2O3) (PO4)2(HPO4)

Two new potassium vanadium phosphates have been prepared and their structures have been determined from analysis of single crystal X-ray data. The two compounds, K₃(VO)(V₂O₃) (PO₄)₂(HPO₄) and K₃(VO)(HV₂O₃)(PO₄)₂(HPO₄), are isostructural, except for the incorporation of an extra hydrogen atom into the nearly identical frameworks. The structures consist of a three-dimensional network of [VO]_n chains connected through phosphate groups to a [V₂O₃] moiety. Magnetic susceptibility experiments indicate that in the case of the di-hydrogen compound, there are no significant magnetic interactions between the three independent vanadium (IV) centers. Crystal data: for K₃(VO)(V₂O₃)(PO₄)₂ (HPO₄), M_r = 620.02, orthorhombic space group Pnma (No. 62), a = 7.023(4) Å, b = 13.309(7) Å, c = 14.294(7) Å, V = 1336(2) ų, Z = 4, R = 5.02%, and R_w = 5.24% for 1238 observed reflections [I > 3σ(I)]; for K₃(VO)(HV₂O₃)(PO₄)₂(HPO₄), M_r = 621.04, orthorhombic space group Pnma (No. 62), a = 6.975(3) Å, b = 13.559(7) Å, c = 14.130(7) Å, V = 1336(1) ų, Z = 4, R = 6.02%, and R_w = 6.34% for 1465 observed reflections [I > 3σ(I)].     

[Gd2(Gly)6(H2O)4](ClO4)6(H2O)5的合成、晶体结构与热化学研究

利用微波技术合成了配合物[Gd₂(Gly)₆(H₂O)₄](ClO₄)₆(H₂O)₅, 进行了化学成分分析、红外表征和热重分析. 应用X衍射仪测定其晶体结构, 该晶体为一维链结构, 属三斜晶系, P 空间群, 晶胞参数: a＝1.1569(17) nm, b＝1.4138(2) nm, c＝1.5642(2) nm, α＝96.910(2)°, β＝102.735(2)°, γ＝105.512(2)°, V＝2.3606(6) nm³, Z＝2, D_c＝2.144 g•cm^－3. 采用精密溶解-反应量热计, 通过设计热化学循环, 计算出了该配合物的标准摩尔生成焓为 －(7960.73±3.23) kJ•mol^－1.