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1.
Synthesis and Crystal Structure of KMgCu4V3O13 . Single crystals of KMgCu4V3O13 were prepared by supercooled melts. It crystallizes with monoclinic symmetry space group C–P21/m (Nr. 11), unit cell dimensions: a = 10.7144 Å, b = 6.0282 Å, c = 8.3365 Å, β = 98.075°, Z = 2. The crystal structure is closely related to the BaMg2Cu8O6O26 type. Cu2+ occurs in an unusual trigonal bipyramidal coordination.  相似文献   

2.
The Crystal Chemistry of Copper Rare-Earth Oxotungstates: (I): triclinic-α-CuTbW2O8, (II): monoclinic-CuInW2O8 and (III): monoclinic-CuYW2O8 Single crystals of (I), (II) and (III) were prepared by recrystallisation in closed systems and examined by X-ray technique. (I): space group C? P1 , a = 7.3080, b = 7.8945, c = 7.1476 Å, α = 115.23, β = 116.21, γ = 56.98°, Z = 2; (II): space group C? C2/c, a = 9.6576, b = 11.6496, c = 4.9863 Å, β = 91.17°, Z = 4; (III): space group C? P2/n, a = 10.0504, b = 5.8214, c = 5.0224 Å, β = 94.23°, Z = 2. The crystal structures are discussed with respect to calculations of the coulombterms of lattice energy and possible valence states of Cu2+ and Mo5+.  相似文献   

3.
Synthesis and Structure of the First Ternary Lead(II) Copper(I) Oxide: PbCu2O2 PbCu2O2 can be prepared by solid state reaction or by precipitation from a basic aqueous solution. Single crystals of the new compound were prepared by recrystallisation from a molten mixture (PbO? Cu2O) and investigated by X-ray diffractometer technique. PbCu2O2 crystallizes isotypically with the homologue silver compound PbAg2O2 (monoclinic with a = 8.223 Å, b = 8.289 Å, c = 6.015 Å, β = 132.62°, Z = 4, space group C? C 1 2/c 1). The crystallographic data from the X-ray investigation are reported. The structure is built by endless [PbO4/4]- and [CuO2/4]-chains. Pb2+ has a one-sided asymmetric coordination with four next oxygen neighbours and Cu+ forms a stretched dumbbell with two oxygen atoms.  相似文献   

4.
The Structures of the Hexagonal Elpasolite-Type Compounds Ba3NiSb2O9 and Ba3CuSb2O9 The results of an X-ray single crystal study of the hexagonal elpasolite Ba(NiSb2)(6)O9 are given. (Space group: C; a = b = 5.837 Å, c = 14.392 Å; Z = 2). The structure can be described by close-packed BaO3 layers alternating in the sequence c c h c c h … (hex. BaTiO3 type). Groups of two octahedra with common faces are connected by SbO6 octahedra via common corners. They are occupied alternately by Ni and Sb. The final reliability index was R = 3.0%. The Cu2+-compound is of the same structural type. The ligand field and EPR spectra are discussed in comparison with related Ni2+ and Cu2+ compounds.  相似文献   

5.
On Hexagonal Perovskites with Cationic Vacancies. XXVI. Ba12Ba2 2/3M 1/32O333 (MV = Nb, Ta) – the First Stacking Polytypes of a Rhombohedral 36 L-Type In the systems BaO? MO5(MV = Nb, Ta) for a Ba:MV ratio of 2:1 polymorphism is observed. Here the low temperature modifications are described. They crystallize in a rhombohedral 36 L structure with three formula units Ba12Ba2 2/3M 1/32O333 for the trigonal setting (MV = Nb: a = 5.922 Å; c = 93.25 Å; Ta: a = 5,922 Å; s = 93.4 Å).  相似文献   

6.
Synthesis and Structure of a New form of CuYMo2O8 Single crystals of a new form of CuYMo2O8 were prepared and investigated by X-ray diffractometer technique [space group D-Pbca; a = 10.160 Å, b = 9.701 Å, c = 14.527 Å; Z = 8]. CuYMo2O8 represents a new structure type characterised by MoO4-tetrahedrons, Cu+ with coordination number 2 + 1 and square antiprisms around Y3+. The crystal structure and the Cu+ coordination are discussed.  相似文献   

7.
The first Alkaline Alkaline-Earth Oxocuprate (II, III): NaBa2Cu22+Cu3+O6 The compound NaBa2Cu3O6 was prepared by heating of Na2O2, BaO2, Cu2O in closed Ag-tubes. X-ray single crystal investigations led to orthorhombic symmetry, space group D-Fmmm; a = 8.4229; b = 11.4418; c = 14.4063 Å; Z = 8. Cu2+ and Cu3+ show square planar polygones of four and Na+ trigonal prisms of six O2?. The two barium point positions show coordination numbers C.N. = 8 and 6 + 4. The crystal structure is discussed.  相似文献   

8.
On Hexagonal Perovskites with Cationic Vacancies. XVI. Rhombohedral 12 L-Stacking Polytypes Ba3AIIIM □O12 with MV = Nb, Ta The white quaternary oxides Ba3LaM□O12 with MV = Nb, Ta belong to the group of hexagonal perovskites with cationic vacancies. They crystallize in a rhombohedral 12 L-structure (sequence (hhcc)3; space group R3 m) with a = 5.751 Å; c = 28.11 Å (MV = Nb); a = 5.746 Å; c = 28.20 Å (Ta) and Z = 3. Signs for the formation of isotypic compounds with AIII = Pr, Nd could be obtained as well.  相似文献   

9.
Synthesis and Investigation of NiNb2O6 Single Crystals of Columbite and Rutil Type C-NiNb2O6 (columbite type) and R-NiNb2O6 (rutil type) single crystals were prepared by solid state reactions. C-NiNb2O6 a = 14.032; b = 5.687; c = 5.033 Å, space group D—Pbcn. R-NiNb2O6 a = 4.710; c = 3.038 Å, space group D—P42/mnm. The metal positions of the rutil structure are statisticaly occupied by Ni2+ and Nb5+ ions. R-NiNb2O6 is in respect to lower temperatures a metastable compound.  相似文献   

10.
A Contribution on the Crystal Structure of CuYW2O8, CuHoW2O8, and CuYW2O8 Single crystals of (I) CuY2O8, (II), CuHoW2O8, and (III) CuYbW2O8 were prepared and investigated by X-ray technique. (I) crystallizes with triclinic symmetry, space group C? P1 (a = 5.939 Å, b = 6.042 Å, c = 5.025 Å; α = 112.30°, β = 111.77°; Z = 1). (II) and (III) belong to monoclinic symmetry, space group C? P2/n (II) (a = 10.045 Å, b = 5.808 Å, c = 5.021 Å; β = 94.38°; z = 2 (III) a = 9.948 Å, b = 5.824 Å, c = 5.008 Å; β = 93.36°; Z = 2). The crystal structures will be discussed with respect to other to copper rare earth tungstates.  相似文献   

11.
A new Alkaline-Alkaline-Earth-Copper-Oxovanadate: Kba3Ca4Cu3V7O28 . Single crystals of Kba3Ca4Cu3V7O28 were prepared by solid state reactions below the melting point of the reaction mixture. It crystallizes with hexagonal symmetry, space group C?P63mc, a=11.160, c=12.428 Å, Z=2. Kba3Ca4Cu3V7O28 represents a new structure type with special coordination polyhedra around Ba2+, trigonal prisms and octahedra around Ca2+ and Cu2+ inside square pyramids. The crystal structure will be shown and discussed.  相似文献   

12.
On Ba(MgZn)V2O8, BaMn2V2O8, and Ba1/2Sr1/2Ni2V2O8 Ba(Mg, Zn)V2O8 (A), BaMn2V2O8 (B) and Ba1/2Sr1/2Ni2V2O8 (C) were prepared by solid state reactions (A and B) and crystallization from a melt (C) respectively. (A? C) crystallize in the space group: D-I41/acd, Nr. 142. [Lattice constants (A): a = 12.4524(57) Å, c = 8.4408(36) Å; (B): a = 12.5563(14) Å, c = 8.5942(9) Å; (C): a = 12.2248(20) Å, c = 8.3245(15) Å]. (A), (B) and (C) are isotypic to SrNi2V2O8 but showing higher symmetry.  相似文献   

13.
Synthesis and Crystal Structure of [N(Hex)4] [Cu2(CN)3] [N(Hex)4][Cu2(CN)3] has been prepared by solvothermal reaction of CuCN with Tetra‐n‐hexylammoniumiodide in acetone. The crystal structure is built up by condensed (CuCN)6 and (CuCN)7 rings, forming a zeolith type cyanocuprate(I) framework [Cu2(CN)3]. Space group R3; α = 44.482(6), c = 21.283(4) Å, V = 36471(9) Å3; Z = 9.  相似文献   

14.
Na2BaCuV2O8: A New Structure Type of the Alkaline-Alkaline Earth Copper Oxovanadates Single crystals of Na2BaCuV2O8 were prepared by a high temperature flux. It crystallizes with monoclinic symmetry space group C–C2/c, a = 9.4329 Å, b = 5.6858 Å, c = 14.0488 Å, β = 92.344° Z = 4 and represents a new structure type. The crystal structure show VO4 tetrahedra, stretched CuO6 octahedra, trigonal bipyramids around Na+ and a BaO10+2 polyedron.  相似文献   

15.
A Contribution on CuPrMo2O8 and CuTbMo2O8 Single crystals of (I): CuPrMo2O8 and (II): CuTbMo2O8 were prepared by solid state reactions in closed copper tubes. They crystallize with orthorhombic symmetry, space group D-Pbca, (I): a = 10.4114, b = 9.8917, c = 14.8287 Å, (II): a = 10.2243, b = 9.7385, c = 14.6000, Z = 8. Both compounds are isotypic to CuYMo2O8, showing isolated MoO4 tetrahedra, square antiprismatic coordination of Ln3+ and Cu+ besides one edge of an O2? triangle. Calculations of the coulombterm of lattice energy support the oxidation state Cu2+ in combination with mixed valences of Mo6+ and Mo5+ on the molybdenum point positions.  相似文献   

16.
A Change of Structure Type in the Oxides BaCoGd2O5, BaCoDy2O5, and BaCoY2O5 (I) BaCoGd2O5, (II) BaCoDy2O5, and (III) BaCoY2O5 were prepared for the first time and examined by single crystal work. (I) and (II) belong to the BaNiLn2O5-type. (I): a = 3.770; b = 5.860; c = 11.620 Å; Z = 2; (II): a = 3.755; b = 5.798; c = 11.514 Å; Z = 2; space group D–Immm. (III) crystallizes in the BaCuLn2O5-type, space group D–Pnma, a = 12.287; b = 5.713; c = 7.067 Å; Z = 4. The coordination of Co2+ changes from (I, II) to (III) from octahedral to tetragonal pyramidal.  相似文献   

17.
Two coordination polymers {[Cd(phen)](C6H8O4)3/3} ( 1 ) and {[Cd(phen)](C7H10O4)3/3} · 2H2O ( 2 ) were structurally characterized by single crystal X‐ray diffraction methods. In 1 (C2/c (no. 15), a = 16.169(2)Å, b = 15.485(2)Å, c = 14.044(2)Å, β = 112.701(8)°, U = 3243.9(7)Å3, Z = 8), the Cd atoms are coordinated by two N atoms of one phen ligand and five O atoms of three adipato ligands to form mono‐capped trigonal prisms with d(Cd‐O) = 2.271‐2.583Å and d(Cd‐N) = 2.309, 2.390Å. The [Cd(phen)] moieties are bridged by adipato ligands to generate {[Cd(phen)](C6H8O4)3/3} chains, which, via interchain π—π stacking interactions, are assembled into layers. Complex 2 (P1¯(no. 2), a = 9.986(1)Å, b = 10.230(3)Å, c = 11.243(1)Å, α = 66.06(1)°, β = 87.20(1)°, γ = 66.71(1)°, U = 955.7(2)Å3, Z = 2) consists of {[Cd(phen)](C7H10O4)3/3} chains and hydrogen bonded H2O molecules. The Cd atoms are pentagonal bipyramidally coordinated by two N atoms of one phen ligand and five O atoms of three pimelato ligands with d(Cd‐O) = 2.213—2.721Å and d(Cd‐N) = 2.329, 2.372Å. Through interchain π—π stacking interactions, the {[Cd(phen)](C7H10O4)3/3} chains resulting from [Cd(phen)] moieties bridged by pimelato ligands are assembled in to layers, between which the hydrogen bonded H2O molecules are sandwiched.  相似文献   

18.
Ba2BiV3O11 containing Bismuth within closed Coordination A new barium bismuth oxovanadate, Ba2BiV3O11, was prepared and investigated by X-Ray single crystal technique. It crystallizes with monoclinic symmetry space group C—P21/a, lattice constants a = 24.6473; b = 7.7347; c = 5.6375 Å, β = 103.16°; Z = 4. Octahedra arround Bi3+, tetrahedra and double tetrahedra arround V5+ form a tunnel structure. The tunnel positions are occupied by Ba(2).  相似文献   

19.
About Ternary Oxocuprates. X. On Ba2Cu3O4Cl2 The preparation of Ba2Cu3O4Cl2 and results by single crystal X-ray methods are described (a = 5.517, c = 13.808 Å; Space group D–I4/mmm). A so far unknown arrangement of square coordinated Cu2+ was detected. The Cu2+/O2?-squares are partly completed to a distorted octahedral coordination by two Cl?.  相似文献   

20.
Synthesis and Crystal Structure of Cu6Mo5O18 Single crystals of the hitherto unknown compound Cu6Mo5O18 were prepared and investigated by X-ray methods (a = 18.884(19), b = 6.273(7), c = 15.259(23) Å, β = 130.40(5)°, space group C–C2/c, Z = 4). The typical features of the structure are described and compared with the crystal chemistry of oxocuprates(I). Observed and calculated powder patterns show that the correct composition of the earlier described compound Cu6Mo4O15 is Cu6Mo5O18.  相似文献   

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