Synthesis and crystal structural study of ternary molybdate NaMg3In(MoO4)5

We have synthesized single crystals of a temary molybdate NaMg₃In(MoO₄)₅ and cam'ed out an X-ray structural study (a KM-4 automatic difiactometer, MoK, radiation, 4503 F, R = 0.047). The triclinic unit cell dimensions are a = 7.0476(7), b = 17.935(2), c = 6.9849(7)Å, = 87.650(9), = 100.980(8), = 92.510(9)°, V= 865.5(2) A³, Z = 2, and space group P^–1. The crystal structure involves MoO₄ tetrahedra and (Mg, In)0₆ octahedra forming a three-dimensional framework with Na atoms located in its cavities. The compound melts at 990°C with decomposition.Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Institute of Physics, Siberian Branch, Russian Academy of Sciences. Buryatian Institute of Natural Sciences, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 34, No. 5, pp. 147–151, September–October, 1993.Translated by T. Yudanova     

Crystal structure investigation of ternary molybdate K(Mg0.5Zr0.5).(MoO4)2

Crystals of K(Mg_0.5Zr_0.5).(MoO₄)₂ were grown, and the composition and crystal structure of the compound were refined in an X-ray diffraction study (CAD-4 automatic diffractometer, MoK_α radiation, 475 F(hkl), R=0.022). The parameters of the trigonal unit cell are: a=5.763(1); c=7.187(1) Å,Z=1, space group P3m1. A typical feature of a glaserite-like structure is atomic arrangement in two layers: at z=0 the Mg and Zr atoms are statistically distributed in the oxygen octahedra, and at z=0.5 the K atoms are distributed inside the icosahedra. In the second layer, Mo atoms with tetrahedral environment are also distributed.     

Crystal structure of a new ternary molybdate Rb5CeZr(MoO4)6

A ternary salt system Rb₂MoO₄-Ce₂(MoO₄)₃-Zr(MoO₄)₂ is studied by powder XRD. Single crystals of 5:1:2 ternary rubidium-cerium-zirconium molybdate Rb₅CeZr(MoO₄)₆ are obtained by solution melt crystallization under spontaneous nucleation conditions. The crystal structure is solved by X-ray crystallography (X8 APEX automated diffractometer, MoK _?? radiation, 1274 F(hkl), R = 0.0456). The parameters of a trigonal unit cell are: a = b = 10.7248(2) ?, c = 38.796(1) ?, V = 3864.52(14) ?³, Z = 6, $R\bar 3c$ space group. The three-dimensional complex framework comprises Mo tetrahedra linked to two independent (Ce,Zr)O₆ octahedra. Two types of rubidium atoms occupy large cavities of the framework.     

Crystal structure investigation of ternary molybdate K5(Mn0.5Zr1.5).(MoO4)6

Crystals of K₅(Mn_0.5Zr_1.5).(MoO₄)₆ were grown, and the crystal structure of this compound was refined in an X-ray diffraction study (CAD-4 automatic diffractometer, MoK_α radiation, 1183 |F(hkl)|, R=0.027). The parameters of the trigonal unit cell are: a=b=10.584(1); c=37.576(3) Å; V=3645.4(3) ų; space group R3c; d_calc=3.606 g/cm³. In the structure, the altermating Mo tetrahedra and (Mn, Zr) octahedra form a three-dimensional mixed framework whosevoids contain potassium atoms of three types. The distribution of the Mn and Zr cations in two crystallographic positions has been refined.     

Phase equilibria in the Tl2MoO4-Fe2(MoO4)3-Hf(MoO4)2 system and the crystal structure of ternary molybdate Tl(FeHf0.5)(MoO4)3

The subsolidus region of the ternary salt system Tl₂MoO₄-Fe₂(MoO₄)₃-Hf(MoO₄)₂ was studied by X-ray powder diffraction. New compounds Tl₅FeHf(MoO₄)₆ (5: 1: 2) and Tl(Fe,Hf_0.5)(MoO₄)₃ (1: 1: 1). were found to be formed in this system. Crystals of new ternary molybdate of the composition Tl(FeHf_0.5)(MoO₄)₃ were grown by spontaneous flux crystallization. Its composition and crystal structure were refined based on X-ray diffraction data. The mixed three-dimensional framework of the crystal structure is composed of Mo tetrahedra sharing O vertices with (Fe,Hf)O₆ octahedra. The thallium atoms occupy wide channels in the framework.     

Phase equilibria in the Tl2MoO4-Nd2(MoO4)3-Hf(MoO4)2 system and the crystal structure of double molybdate TlNd(MoO4)2

The Tl₂MoO₄-Nd₂(MoO₄)₃-Hf(MoO₄)₂ system was studied in the subsolidus region using X-ray powder diffraction. New triple molybdates were found to exist in this system: Tl₅NdHf(MoO₄)₆ (5: 1: 2), TlNdHf_0.5(MoO₄)₃ (1: 1: 1), and Tl₂NdHf₂(MoO₄)_6.5 (2: 1: 4). The first TlNd(MoO₄)₂ single crystals were grown from melt solutions with spontaneous nucleation. Their crystal structure was refined from X-ray diffraction data (Bruker X8 Apex automated diffractometer, MoK _α radiation, 386 F(hkl), R = 0.0136). The tetragonal unit cell parameters are as follows: a = 6.3000(2) Å, c = 9.5188(5) Å, V = 377.80(3) ų, Z = 2, ρ_calcd = 5.876 g/cm³, space group P4/nnc. The structure is a framework built of NdO₈ and TlO₈ tetragonal antiprisms linked via shared lateral edges and alternating in the checkerboard order. Layers share oxygen vertices with MoO₄ interlayer tetrahedra and are linked into the framework.     

Structure of BaGd2（MoO4）4 Crystal

The title compound belongs to monoclinic,space group C2/c with a=5.2694(1),b=12.6659(4),c=19.4108(2) ,β=91.504(2)°,V=1295.06(5) 3,Z=4 and Dc=5.599 g/cm3. The structure of BaGd2(MoO4)4 contains a MoO4 tetrahedron,a distorted GdO8 polyhedron,and Ba2+ ions in a tenfold coordination. The GdO8 polyhedra are linked together through edge-sharing to give a two-dimensional Gd layer. The MoO4 tetrahedra connected to the Gd atoms are capped up and down the Gd layer through common oxygen apices,thus forming a new Gd-Mo layer. Finally,the Gd-Mo layers are held together through bridging BaO10 polyhedra to form a three-dimensional framework. Since the Ba-μ3-O bond has a large average distance of 2.888 ,this structural characteristic will result in a cleavage along the (001) plane.     

Phase formation in the Rb2MoO4-Er2(MoO4)3-Hf(MoO4)2 system and the crystal structure of new triple molybdate Rb5ErHf(MoO4)6

The subsolidus region of the Rb₂MoO₄-Er₂(MoO₄)₃-Hf(MoO₄)₂ ternary salt system is studied using X-ray powder diffraction. A novel 5: 1: 2 triple molybdate, Rb₅ErHf(MoO₄)₆, is found to form in the system. Crystals of Rb₅ErHf(MoO₄)₆ are flux-grown under spontaneous nucleation conditions. The composition and crystal structure of Rb₅ErHf(MoO₄)₆ are refined in a single-crystal X-ray diffraction experiment (X8 APEX diffractometer, MoK _α radiation, 1753 reflections, R = 0.0183). The crystals are trigonal; a = 10.7511(1) Å, c = 38.6543(7) Å, V = 3869.31(9) ų, d _calc = 4.462 g/cm³, Z = 6, space group $R\bar 3c$ . The mixed three-dimensional framework of the structure is formed of MoO₄ tetrahedra, each sharing corners with two ErO₆ and HfO₆ octahedra. Two types of Rb atoms occupy large cavities of the framework. The distribution of the Er³⁺ and Hf⁴⁺ cation over two positions is refined in the course of structure solution.     

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.     

Phase equilibria in the systems Rb2MoO4-R2(MoO4)3-Hf(MoO4)2 (R = Al, In, Sc, Fe(III)) and the crystal structure of double molybdate RbFe(MoO4)2

The systems Rb₂MoO₄-R₂(MoO₄)₃-Hf(MoO₄)₂ have been investigated in the subsolidus region by X-ray powder diffraction, DTA, and IR spectroscopy. Triple molybdates of the composition 5: 1: 2 are formed in the systems with R = Al, In, Sc, and Fe. Molybdates of composition 5: 1: 3 and 1: 1: 1 are found in the iron(III)-containing system in addition to the 5: 1: 2 molybdate. Single crystals of the double molybdate RbFe(MoO₄)₂, which is formed in the Rb₂MoO₄-Fe₂(MoO₄)₃ system, have been grown. The structure of this double molybdate has been refined using X-ray diffraction data (X8 APEX automated diffractometer, MoK _α radiation, 373 F(hkl), R = 0.0287). The trigonal unit cell parameters are the following: a = b = 5.6655(2) Å, c = 7.5061(4) Å, V = 208.65(1) ų, Z = 1, ρ_calc = 3.670 g/cm³, space group R3m1. The structure is formed by layers of FeO₆ octahedra sharing corners with MoO₄ tetrahedra and RbO₁₂ icosahedra.     

Li3Al(MoO4)3, a lyonsite molybdate

Trilithium aluminium trimolybdate(VI), Li₃Al(MoO₄)₃, has been grown as single crystals from α‐Al₂O₃ and MoO₃ in an Li₂MoO₄ flux at 998 K. This compound is an example of the well known lyonsite structure type, the general formula of which can be written as A₁₆B₁₂O₄₈. Because this structure can accomodate cationic mixing as well as cationic vacancies, a wide range of chemical compositions can adopt this structure type. This has led to instances in the literature where membership in the lyonsite family has been overlooked when assigning the structure type to novel compounds. In the title compound, there are two octahedral sites with substitutional disorder between Li⁺ and Al³⁺, as well as a trigonal prismatic site fully occupied by Li⁺. The (Li,Al)O₆ octahedra and LiO₆ trigonal prisms are linked to form hexagonal tunnels along the [100] axis. These polyhedra are connected by isolated MoO₄ tetrahedra. Infinite chains of face‐sharing (Li,Al)O₆ octahedra extend through the centers of the tunnels. A mixed Li/Al site, an Li, an Mo, and two O atoms are located on mirror planes.     

LiFe(MoO4)2, LiGa(MoO4)2 and Li3Ga(MoO4)3

The structures of lithium iron dimolybdate, LiFe(MoO₄)₂, and lithium gallium dimolybdate, LiGa(MoO₄)₂, are shown to be isomorphous with each other. Their structures consist of segregated layers of LiO₆ bicapped trigonal bipyramids and Fe(Ga)O₆ octahedra separated and linked by layers of isolated MoO₄ tetrahedra. The redetermined structure of trilithium gallium trimolybdate, Li₃Ga(MoO₄)₃, shows substitional disorder on the Li/Ga site and consists of perpendicular chains of LiO₆ trigonal prisms and two types of differently linked Li/GaO₆ octahedra.     

Crystal structure investigation of ternary molybdates Li3Ba2Ln3(MoO4)3 (Ln=Gd,Tm)

Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Institute of Physics, Siberian Branch, Russian Academy of Sciences. Buryat Institute of Natural Sciences, Siberian Branch, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 3, pp. 126–130, May–June, 1992.     

Structure and Crystal Growth of Li2Zn2（MoO4）3

Single crystal of Li2Zn2(MoO4)3 has been grown from a flux of Li2MoO4 by the top-seeded solution-growth method,and its structure was refined by the Rietveld method. It belongs to the orthorhombic system,space group Pnma with a=5.1114,b=10.4906 and c=17.6172. Good agreement between the experimental and calculated profile(Rp=6.69%,Rwp=9.73% and Rexp= 6.58%) was reached.     

Double molybdate Tl2Mg4(MoO4)3: Synthesis, structure, and properties

Single crystals of molybdate Tl₂Mg₂(MoO₄)₃ are grown, and its crystal structure is refined in an X-ray diffraction experiment (an automated diffractometer, MoK _α radiation, 914 F(hkl) reflections, R = 0.0459). The crystal are cubic with a = b = c = 10.700(1) Å, V = 1225.0(2) ų, Z = 4, space group P2₁3. The mixed 3D framework of the structure is built of MoO₄ tetrahedra and two types of corner-sharing MgO₆ octahedra. Two types of thallium atoms occupy large interstices.     

Synthesis and crystal structure of the binary molybdate Li8Bi2(MoO4)7

Single crystals of Li₈Bi₂(MoO₄)₇ were synthesized; the composition and crystal structure of this compound were determined from X-ray diffraction data (CAD-4 automatic diffractometer, MoK_a radiation, 1767 reflections, R = 0.031). The parameters of the tetragonal unit cell are as follows: a = 21.130, c = 5.287 Å, Z = 4, space group -14. The structure of the binary molybdate is a three-dimensional mixed framework of MoO₄ tetrahedra of four varieties, Bi eight-vertex potyhedra, and Li(l)O₆ and Li(2)O₆ octahedra. The large channels of the framework along the c axis contain MoO₄ tetrahedra of the fifth variety with Li(3)O₄ and Li(4)O₄ tetrahedra attached to them via common vertices and forming four symmetrically related chains of pyroxene type. The structure of Li₈Bi₂(MoO₄)₇ involves structural fragments of Li₃Fe(MoO₄)₃ and a-RbPr(MoO₄)₂ and is a new structural type in the class of binary molybdates and tungstates of uniand trivalent metals.