Phase formation in Cs2MoO4-MMoO4-Zr(MoO4)2 (M = Mn, Mg, Co, Zn) systems and crystal structure of new double molybdates Cs2MnZr2(MoO4)6 and Cs2MnZr(MoO4)4

Subsolidus phase relations in the Cs₂MoO₄-MMoO₄-Zr(MoO₄)₂ (M = Mn, Zn) ternary systems were determined, and two groups of new isostructural triple molybdates were synthesized: Cs₂MZr(MoO₄)₄ and Cs₂MZr₂(MoO₄)₆ (M = Mn, Mg, Co, Zn). Cs₂MnZr₂(MoO₄)₆ and Cs₂MnZr(MoO₄)₄ crystals were grown by spontaneous flux crystallization and used in structure solution for both groups of compounds. The Cs₂MnZr₂(MoO₄)₆ structure (a =13.4322(2) ?, c = 12.2016(3) ?, group R3, Z = 3, R = 0.0367) is a new structure type characterized by a mixed three-dimensional framework built of corner-sharing MoO₄ tetrahedra and (M, Zr)O₆ octahedra where large channels are occupied by cesium cations. Cs₂MnZr₂(MoO₄)₄ (a =5.3890(1) ?, c = 8.0685(3) ?, space group P $ \bar 3 $ \bar 3 m1, Z = 0.5, R = 0.0247) has the layered glaserite-like KAl(MoO₄)₂ type structure, where Al³⁺ octahedral positions are randomly occupied by a 0.5M²⁺ + 0.5Zr⁴⁺ mixture.     

Subsolidus phase relations in the Na2MoO4-CoMoO4-Cr2(MoO4)3 system

Triple molybdate NaCoCr(MoO₄)₃, a phase of variable composition Na₂MoO₄-CoMoO₄-Cr₂(MoO₄)₃ (0 ≤ x ≤ 0.5) having nasicon structure (space group R $ \bar 3 $ \bar 3 c), and triple molybdate NaCo₃Cr(MoO₄)₅ crystallizing in triclinic space group P $ \bar 1 $ \bar 1 were synthesized in the subsolidus region of the Na₂MoO₄-CoMoO₄-Cr₂(MoO₄)₃ ternary salt system. Crystal parameters were calculated for the newly synthesized molybdates and phases. The vibration spectra of Na_{1 − x} Co_{1 − x} Cr_{1 + x} (MoO₄)₃ and electrophysical properties were studied. Upon Na + Co → Cr(III) substitution, chromium cations are distributed to cobalt sites and additional vacancies are generated in the sodium sublattice.     

Crystal structure of a new coordination polymer [LaAg(Pydc)(HPydc)(C2O4)0.5(H2O)2]n (H2Pydc = pyridine-3,5-dicarboxylic acid)

A new 3D coordination polymer, [LaAg(Pydc)(HPydc)(C₂O₄)_0.5(H₂O)₂] _n (I) (H₂Pydc = pyridine-3,5-dicarboxylic acid), has been hydrothermally synthesized and characterized by elemental analyses and single crystal X-ray diffraction. The X-ray diffraction analysis reveals that I (C₁₅H₁₁AgLaN₂O₁₂) crystallizes in triclinic space group P $ \bar 1 $ \bar 1 and features an interesting 3D framework constructed by 2D layers via strong Ag-Ag interactions. Unit cell parameters for I (n = 1): a = 7.749(2), b = 8.316(1), c = 14.239(3) ?, α = 97.64(2)°, β = 100.12(2)°, γ = 94.37(2)°, and Z = 2.     

Phase formation in the K2MoO4-Lu2(MoO4)-Hf(MoO4)2 system and the structural study of triple molybdate K5LuHf(MoO4)6

Interactions in the ternary system K₂MoO₄-Lu₂(MoO₄)₃-Hf(MoO₄)₂ have been studied by X-ray powder diffraction and differential thermal analysis. A new triple (potassium lutetium hafnium) molybdate with the 5: 1: 2 stoichiometry has been found. Single crystals of this molybdate have been grown. Its X-ray diffraction structure has been refined (an X8 APEX automated diffractometer, MoK _α radiation, 1960 F(hkl), R = 0.0166). The trigonal unit cell has the following parameters: a = 10.6536(1) ?, c = 37.8434(8) ?, V = 3719.75(9) ?, Z = 6, space group R c. The mixed 3D framework of the structure is built of Mo tetrahedra sharing corners with two independent (Lu,Hf)O₆ octahedra. Two sorts of potassium atoms occupy large framework voids. Original Russian Text ? E.Yu. Romanova, B.G. Bazarov, R.F. Klevtsova, L.A. Glinskaya, Yu.L. Tushinova, K.N. Fedorov, Zh.G. Bazarova, 2007, published in Zhurnal Neorganicheskoi Khimii, 2007, Vol. 52, No. 5, pp. 815–818.     

Crystal structure of binary molybdate Pr2Hf3(MoO4)9

Crystals of binary praseodymium and hafnium molybdate of Pr₂Hf₃(MoO₄)₉ composition are grown by solution-melt crystallization under spontaneous nucleation conditions. By the X-ray diffraction data (X8 Apex automated diffractometer, MoK _α radiation, 2262 F(hkl), R = 0.0170) its composition and crystal structure are determined. Parameters of the trigonal unit cell are: a = b = 9.8001(1) ? c = 58.7095(8) ?, V = 4883.15(10) ?³, Z = 6, space group R c. The crystal structure is composed of three types of polyhedra: MoO₄ tetrahedra, HfO₆ octahedra, and nine-vertex PrO₉. All three types of polyhedra are bonded among themselves by common oxygen vertices of bridging MoO₄ tetrahedra forming an openwork three-dimensional structure. Original Russian Text Copyright ? 2009 by B. G. Bazarov, V. G. Grossman, R. F. Klevtsova, A. G. Anshits, T. A. Vereshchagina, L. A. Glinskaya, Yu. L. Tushinova, K. N. Fedorov, and Zh. G. Bazarova __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 3, pp. 587–590, May–June, 2009.     

Hydrothermal synthesis and crystal structure of lithium scandium orthophosphate Li2Sc[H(PO4)2]. The Li2MIII[H(PO4)2] family (MIII = Fe, Sc, In)

Conditions of the hydrothermal synthesis of scandium hydrogen orthophosphate Li₂Sc[H(PO₄)₂] (I) have been studied and the range of its monomineral crystallization have been determined. The existence of bound hydrogen in the structure has been confirmed by IR spectroscopy. The crystals of I are monoclinic: a = 4.857(1) ?, b = 8.198(2) ?, c = 7.664(2) ?, β = 104.097(5)°, space group P2₁/n, Z = 2. The structure was solved by direct methods and refined by full-matrix least-squares calculation in the anisotropic approximation for all non-hydrogen atoms, R _obs = 0.0215, R _wall = 0.0335 (705 reflections with I > 3σ(I)). The basis of the structure is a mixed anionic para-framework {Sc[H(PO₄)₂]}_3∞²⁻, composed of vertex-sharing ScO₆ octahedra and PO₄ tetrahedra. The structural unit of the para-framework is the microblock [ScP₆O₂₄] with symmetry $ \bar 1 $ \bar 1 . The microblocks are condensed in columns running in the [100] direction to form through channels filled with Li⁺ cations (CN = 5). A model with splitting of the hydrogen atom position implying the formation of a strong asymmetric nonlinear H-bond has been suggested and considered. The compound is stable to 400°C. The results of studying compound I are presented together with the data on the Fe- and In-containing Li₂M^III[H(PO₄)₂] analogues.     

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.     

Interactions in the subsolidus region of the Na2MoO4-NiMoO4-Fe2(MoO4)3 system

Phase relations have been investigated in the subsolidus region of the Na₂MoO₄-NiMoO₄-Fe₂(MoO₄)₃ system by X-ray diffraction, differential thermal analysis, and vibrational spectroscopy. The phase of variable composition Na_1−x Ni_1−x Fe_1+x (MoO₄)₃(0≤x≤0.5) with the NASICON structure (space group R c) and the NaNi₃Fe(MoO₄)₅ ternary molybdate crystallizing in the triclinic crystal system (space group P ) have been obtained. A high conductivity was found in Na_1−x Ni_1−x Fe_1+x (MoO₄)₃, which allows one to consider this phase of variable composition as a promising solid electrolyte with sodium ion conduction. Original Russian Text ? N.M. Kozhevnikova, A.V. Imekhenova, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 4, pp. 695–700.     

Crystal structure and magnetic properties of Li,Cr-containing molybdates Li3Cr(MoO4)3, LiCr(MoO4)2 and Li1.8Cr1.2(MoO4)3

Single crystals of LiCr(MoO₄)₂, Li₃Cr(MoO₄)₃ and Li_1.8Cr_1.2(MoO₄)₃ were grown by a flux method during the phase study of the Li₂MoO₄-Cr₂(MoO₄)₃ system at 1023 K. LiCr(MoO₄)₂ and Li₃Cr(MoO₄)₃ single phases were synthesized by solid-state reactions. Li₃Cr(MoO₄)₃ adopts the same structure type as Li₃In(MoO₄)₃ despite the difference in ionic radii of Cr³⁺ and In³⁺ for octahedral coordination. Li₃Cr(MoO₄)₃ is paramagnetic down to 7 K and shows a weak ferromagnetic component below this temperature. LiCr(MoO₄)₂ is isostructural with LiAl(MoO₄)₂ and orders antiferromagnetically below 20 K. The magnetic structure of LiCr(MoO₄)₂ was determined from low-temperature neutron diffraction and is based on the propagation vektor . The ordered magnetic moments were refined to 2.3(1) μ_B per Cr-ion with an easy axis close to the [1 1 1¯] direction. A magnetic moment of 4.37(3) μ_B per Cr-ion was calculated from the Curie constant for the paramagnetic region.The crystal structures of the hitherto unknown Li_1.8Cr_1.2(MoO₄)₃ and LiCr(MoO₄)₂ are compared and reveal a high degree of similarity: In both structures MoO₄-tetrahedra are isolated from each other and connected with CrO₆ and LiO₅ via corners. In both modifications there are Cr₂O₁₀ fragments of edge-sharing CrO₆-octahedra.     

Synthesis of Flower-like NaY(MoO4)2 and Optical Property of NaY(MoO4)2:Eu3+

Flower-like NaY(MoO₄)₂ particles were synthesized through a microwave-assisted hydrother-mal process followed by a subsequent calcination process. The products were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron mi-croscopy. The possible formation mechanism of the flower-like NaY(MoO₄)₂ precursor was proposed. The NaY(MoO₄)₂:Eu³⁺ phosphors were also prepared and their luminescence properties showed the NaY(MoO₄)₂:Eu³⁺ materials with the emission peak at 612 nm had potential application as a red phosphor for white light-emitting diodes. Furthermore, the microwave-assisted hydrothermal process followed by a subsequent calcination process could be extended to prepare the other lanthanide molybdates with the flower-like morphology.     

Synthesis and study of (CN3H6)2[(UO2)2(C2O4)(SeO3)2] by IR spectroscopy and X-ray diffraction

Single crystals of (CN₃H₆)₂[(UO₂)₂(C₂O₄)(SeO₃)₂] were synthesized and studied by IR spectroscopy and X-ray diffraction. The compound crystallizes in the triclinic system with the unit cell parameters a = 7.1169(12) ?, b = 7.4874(10) ?, c = 8.9748(14) ?, α = 88.243(6)°, β = 74.546(6)°, γ = 81.445(6)°, space group P[`1]P\bar 1, Z = 1, R = 0.0304. The main structural units of the crystals are layers of the [(UO₂)₂(C₂O₄)(SeO₃)₂]²⁻ composition; the layers belong to the crystal chemical group A ₂ K ⁰² T ₂³ (A = UO₂²⁺ K ⁰² = C₂O₄²⁻, T ³ = SeO₃^–) of uranyl complexes. Uranium-containing complex groups are linked by electrostatic interactions and a network of hydrogen bonds with CN₃H₆⁺ guanidinium ions to form a three-dimensional framework.     

Syntheses and single-crystal structures of CsTh(MoO4)2Cl and Na4Th(WO4)4

Colorless crystals of CsTh(MoO₄)₂Cl and Na₄Th(WO₄)₄ have been synthesized at 993 K by the solid-state reactions of ThO₂, MoO₃, CsCl, and ThCl₄ with Na₂WO₄. Both compounds have been characterized by the single-crystal X-ray diffraction. The structure of CsTh(MoO₄)₂Cl is orthorhombic, consisting of two adjacent [Th(MoO₄)₂] layers separated by an ionic CsCl sublattice. It can be considered as an insertion compound of Th(MoO₄)₂ and reformulated as Th(MoO₄)₂·CsCl. The Th atom coordinates to seven monodentate MoO₄ tetrahedra and one Cl atom in a highly distorted square antiprism. Na₄Th(WO₄)₄ adopts a scheelite superlattice structure. The three-dimensional framework of Na₄Th(WO₄)₄ is constructed from corner-sharing ThO₈ square antiprisms and WO₄ tetrahedra. The space within the channels is filled by six-coordinate Na ions. Crystal data: CsTh(MoO₄)₂Cl, monoclinic, P2₁/c, Z=4, a=10.170(1) Å, b=10.030(1) Å, c=9.649(1) Å, β=95.671(2)°, V=979.5(2) Å³, R(F)=2.65% for I>2σ(I); Na₄Th(WO₄)₄, tetragonal, I4₁/a, Z=4, a=11.437(1) Å, c=11.833(2) Å, V=1547.7(4) Å³, R(F)=3.02% for I>2σ(I).     

Supramolecular pseudometallacycles in a nickel compound with 4,4-diaminodiphenylmethane: Synthesis and structure of {Ni[(CH2(C6H4NH2)2]2(NO3)2(H2O)2}

The [Ni(DDM)₂(NO₃)₂(H₂O)₂] complex (DDM is 4,4-diaminodiphenylmethane [CH₂(C₆H₄NH₂)₂]) is synthesized, and its structure is determined. The crystals are triclinic, space group P , a = 5.846(1) ?, b = 9.450(2) ?, c = 13.390(3) ?, α = 105.63(3)°, β = 98.13(3)°, γ = 105.84(3)°, V = 666.6(2) ?³, ρ_calcd = 1.553 g/cm³, Z = 2. The Ni(II) ion (in the inversion center) is bound to a distorted octahedral array formed by the nitrogen atoms of the primary amino groups of the DDM molecules and the oxygen atoms of the monodentate nitrato groups and water molecules (Ni(1)-N(3) 2.119(2) ?, Ni(1)-O(1) 2.122(2) ?, Ni(1)-O(w) 2.047(2) ?, angles at the Ni atoms vary in the 85.08(9)°–94.92(9)° interval). The structure contains supramolecular metallacycles formed by the O(w)-H…N(2) hydrogen bonds between the coordinated H₂O molecules and the terminal amino groups of DDM. The metallacycles are joined by the Ni²⁺ ions into infinite chains running in the [111] direction. Original Russian Text ? Yu.V. Kokunov, V.V. Kovalev, Yu.E. Gorbunova, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 11, pp. 1838–1843.     

Crystal and molecular structure of (NH4)2[UO2(NO3)4] and [(NH4)(18C6)]2[UO2(NO3)4]

Single crystals of diammonium tetranitratouranylate (NH₄)₂[UO₂(NO₃)₄] (I) and a new diammonium tetranitratouranylate complex with 18-crown-6 [(NH₄)(18C6)]₂[UO₂(NO₃)₄] (II) have been synthesized by the reaction of diaquadinitratouranyl tetrahydrate with ammonium nitrate in a nitric acid solution and the reaction of the same reagents with 18C6 in an ethanol solution, respectively. The X-ray diffraction analysis of compounds I and II has been performed. Crystals of compounds I and II are monoclinic, Z = 2, space group P2₁/n, a = 6.4075(5) ?, b = 7.7851(7) ?, c = 12.4461(12) ?, β = 101.239(1)°, V = 608. 94(9) ?³ for compound I and a = 10.542(9) ?, b = 8.590(8) ?, c = 22.5019(19) ?, β = 101.632(1)°, V = 2058.3(3) ?³ for compound II. The [UO₂(NO₃)₄]²⁻ complex anion in compounds I and II contains two monodentate and two bidentate cyclic nitrato groups, and the coordination number of uranyl is 6. The 18C6 molecule in the structure of compound II has the classic crown conformation and combined with the ammonium ion by three hydrogen bonds. Compounds I and II formed by electrostatic attraction forces between counterions are stabilized by (NH₄⁺)NH...O(NO₃⁻) interionic hydrogen bonds.     

Crystal structure of [Pd(P(i-Pr)3)2(acac)]BF4

A single crystal X-ray diffraction study is carried out for [Pd(P(i-Pr)₃)₂(acac)]BF₄, T = 150(2) K. Crystal data: a = 10.2935(4) ?, b = 11.3591(5) ?, c = 13.8728(6) ?, α = 89.154(2)°, β = 68.448(1)°, γ = 85.032(1)°, P-1 space group, V = 1502.75(11) ?³, Z = 2, d _x = 1.354 g/cm³.     

Phase equilibrium in the Cs2MoO4-Bi2(MoO4)3-Zn(MoO4)2 system and the crystal structure of new triple molybdate Cs5BiZr(MoO4)6

The subsolidus region of the Cs₂MoO₄-Bi₂(MoO₄)₃-Zr(MoO₄) system was studied by X-ray powder diffraction. Quasi-binary sections were elucidated, and triangulation performed. Triple molybdates with the component ratios 5: 1: 2 (S ₁) and 2: 1: 4 (S ₂) were prepared for the first time. Crystals of cesium bismuth zirconium molybdate of the 5: 1: 2 stoichiometry (Cs₅BiZr(MoO₄)₆) were grown from fluxed melts with spontaneous nucleation. The composition and crystal structure of this triple molybdate were refined using X-ray diffraction data (collected on X8 APEX automated diffractometer, MoK _α radiation, 2348 F(hkl), R = 0.0226). The trigonal unit cell parameters were as follows: a = b = 10.9569(2), c = 39.804(4) Å, V = 4138.4(4) ų, Z = 6, space group R $ \bar 3 The subsolidus region of the Cs₂MoO₄-Bi₂(MoO₄)₃-Zr(MoO₄) system was studied by X-ray powder diffraction. Quasi-binary sections were elucidated, and triangulation performed. Triple molybdates with the component ratios 5: 1: 2 (S ₁) and 2: 1: 4 (S ₂) were prepared for the first time. Crystals of cesium bismuth zirconium molybdate of the 5: 1: 2 stoichiometry (Cs₅BiZr(MoO₄)₆) were grown from fluxed melts with spontaneous nucleation. The composition and crystal structure of this triple molybdate were refined using X-ray diffraction data (collected on X8 APEX automated diffractometer, MoK _α radiation, 2348 F(hkl), R = 0.0226). The trigonal unit cell parameters were as follows: a = b = 10.9569(2), c = 39.804(4) ?, V = 4138.4(4) ?³, Z = 6, space group R c. The mixed-metal three-dimensional framework in this structure is built of Mo tetrahedra and two sorts of (Bi,Zr)O₆ octahedra. Large interstices accommodate two sorts of cesium atoms. The Bi³⁺ and Zr⁴⁺ cation distributions over two positions were refined during structure solution. Original Russian Text ? B.G. Bazarov, T.V. Namsaraeva, R.F. Klevtsova, A.G. Anshits, T.A. Vereshchagina, R.V. Kurbatov, L.A. Glinskaya, K.N. Fedorov, Zh.G. Bazarova, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 9, pp. 1585–1589.     

Cr2(WO4)3和Cr2(MoO4)3的负热膨胀特性研究

用液相反应-前驱物烧结法制备了Cr₂(WO₄)₃和Cr₂(MoO₄)₃粉体。298～1 073 K的原位粉末X射线衍射数据表明Cr₂(WO₄)₃和Cr₂(MoO₄)₃的晶胞体积随温度的升高而增大, 本征线热膨胀系数分别为(1.274±0.003)×10^-6 K^-1和(1.612±0.003)×10^-6 K^-1。用热膨胀仪研究了Cr₂(WO₄)₃和Cr₂(MoO₄)₃在静态空气中298～1 073 K范围内热膨胀行为，即开始表现为正热膨胀，随后在相转变点达到最大值，最后表现为负热膨胀，其负热膨胀系数分别为(-7.033±0.014)×10^-6 K^-1和(-9.282±0.019)×10^-6 K^-1。     

Synthesis, crystal structure and electrical characterization of two new potassium uranyl molybdates K2(UO2)2(MoO4)O2 and K8(UO2)8(MoO5)3O6

Two new potassium uranyl molybdates K₂(UO₂)₂(MoO₄)O₂ and K₈(UO₂)₈(MoO₅)₃O₆ have been obtained by solid state chemistry . The crystal structures were determined by single crystal X-ray diffraction data, collected with MoKα radiation and a charge coupled device (CCD) detector. Their structures were solved using direct methods and Fourier difference techniques and refined by a least square method on the basis of F² for all unique reflections, with R₁=0.046 for 136 parameters and 1412 reflections with I?2σ(I) for K₂(UO₂)₂(MoO₄)O₂ and R₁=0.055 for 257 parameters and 2585 reflections with I?2σ(I) for K₈(UO₂)₈(MoO₅)₃O₆. The first compound crystallizes in the monoclinic symmetry, space group P2₁/c with a=8.250(1) Å, b=15.337(2) Å, c=8.351(1) Å, β=104.75(1)°, ρ_mes=5.22(2) g/cm³, ρ_cal=5.27(2) g/cm³ and Z=4. The second material adopts a tetragonal unit cell with a=b=23.488(3) Å, c=6.7857(11) Å, ρ_mes=5.44(3) g/cm³, ρ_cal=5.49(2) g/cm³, Z=4 and space group P4/n.In both structures, the uranium atoms adopt a UO₇ pentagonal bipyramid environment, molybdenum atoms are in a MoO₄ tetrahedral environment for K₂(UO₂)₂(MoO₄)O₂ and MoO₅ square pyramid coordination in K₈(UO₂)₈(MoO₅)₃O₆. These compounds are characterized by layered structures. The association of uranyl ions (UO₇) and molybdate oxoanions MoO₄ or MoO₅, give infinite layers [(UO₂)₂(MoO₄)O₂]²⁻ and [(UO₂)₈(MoO₅)₃O₆]⁸⁻ in K₂(UO₂)₂(MoO₄)O₂ and K₈(UO₂)₈(MoO₅)₃O₆, respectively. Conductivity properties of alkali metal within the interlayer spaces have been measured and show an Arrhenius type evolution.     

Synthesis and crystal structure of sodium isopolyvanadate [Na2(H2O)8]2H2[V10O28] · 4H2O

The sodium hydrogen oxovanadate [Na₂(H₂O)₈] ₂H₂[V₁₀O₂₈] · 4H₂O was synthesized and studied by TGA, X-ray diffraction, and NMR and IR spectroscopy. The crystals are triclinic, space group P $ \bar 1 $ \bar 1 , a = 8.545(7) ?, b = 10.827(2) ?, c = 11.627(2) ?, α = 105.48(3)°, β = 99.38(3)°, γ = 101.29(3)°, V = 989.9(3) ?³, ρ(calcd) = 2,381 g/cm³, Z= 1.     

Synthesis of Cr2(MoO4)3

Studies on the kinetics and mechanism of the reaction leading to Cr₂(MoO₄)₃ have been made using X-ray diffraction and infrared spectroscopy. The apparent activation energy, E=285±22 kJ/mol has been calculated, based on the Ginstling-Brounstein diffusion controlled model.