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1.
Polyoxometallates are capable of including transition metals in their crystal structures as either discrete cations or heteroatoms. The title compound crystallizes with triclinic symmetry and consists of a centrosymmetric [V10O28]6? anion, a trimeric {[Na(H2O)3][Ni(H2O)6][Na(H2O)3]}4+ cation, an [Ni(H2O)6]2+ cation and four water molecules of crystallization. The compound possesses two Ni atoms (each on independent inversion centres), one as a discrete cation and one in a disodium–nickel trimeric cation involved in the one‐dimensional polycation–polyanion hybrid polymer. The polymers are bound together via hydrogen bonds to the water mol­ecules and the nickel(II) hexahydrate cation. Several structures of decavanadate compounds having transition metal atoms, monovalent cations and [V10O28]6? anions in the ratio 2:2:1 have been reported previously. However, the present compound differs from these in its arrangement of monovalent cations and transition metal atoms.  相似文献   

2.
金属磷酸盐材料在吸附、离子交换、离子传导和催化剂方面有潜在的应用前景[1~5]. 近年来, 通过水热反应合成了一些A-V-P-O化合物. 在这些化合物中, A一般为碱金属或有机阳离子, 如层状结构的[H2N(C4H8)2NH2][(VO)4(OH)4(PO4)2][6] 和[H2N(C2H4)3NH2][(VO)8(HPO4)3(PO4)4*(OH)2]*2H2O[6], 一维链状结构的 [H2NCH2CH2NH3(VO)(PO4)][7], 手性双螺旋结构的 [(CH3)2NH2]K4[(VO)10(H2O)2(OH)4(PO4)7]*H2O[8]以及具有三维骨架结构的化合物 [H3N(CH2)3NH3K(VO)3(PO4)3][9], [H3N(CH2)3NH3]2[V(H2O)2(VO)6(OH)2(HPO4)3(PO4)5]*3H2O[10]和[H3N(CH2)2NH3][(VO)3(H2O)2(PO4)2(HPO4)4][11].  相似文献   

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The structure of two trinuclear iron acetates [Fe3O(CH3COO)6(H2O)3]Cl· 6H2O (I) and [Fe3O(CH3COO)6(H2O)3][FeCl4] · 2CH3COOH (II) was determined by X-ray diffraction analysis. Crystals I and II are ionic and belong to the orthorhombic system with parameters a = 13.704(3), b = 23.332(5), c = 9.167(2) Å, R = 0.0355, space goup P21212 for I and a = 10.145(4), b = 15.323(6), c = 22.999(8) Å, R = 0.0752, space group Pbc21 for II. The complex cation [Fe3O(CH3COO)6(H2O)3]+ has a μ3-O-bridged structure typical for trinuclear iron (III) compounds. As shown by Mössbauer spectroscopy, the iron(III) ions are in the high-spin state. In trinuclear cations, antiferromagnetic exchange interaction takes place between the Fe(III) ions with the exchange parameter J = -26.69 cm?1 for II (Heisenberg-Dirac-Van Vleck model for D3h, symmetry).  相似文献   

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合成了两种固态稀土丙氨酸配合物[Ho2(Ala)4(H2O)8]Cl6和[ErY(Ala)4(H2O)8](ClO4)6 (Ala为丙氨酸),用量热和热分析方法研究了这两种配合物的热力学性质.用全自动高精密绝热量热计测定了在78~377 K温区内的低温热容.对于[Ho2(Ala)4(H2O)8]Cl6,在214~255 K温区内发现一固-固相变,其相变温度为235.09 K.对于[ErY(Ala)4(H2O)8](ClO4)6,在99~121 K温区内也发现一固-固相变,其相变温度为115.78 K. [Ho2(Ala)4(H2O)8]Cl6固-固相变焓为3.02 kJ• mol-1,相变熵为12.83 J•K-1•mol-1; [ErY(Ala)4(H2O)8](ClO4)6 固-固相变焓为1.96 kJ•mol-1,相变熵为16.90 J•K-1•mol-1.同时,用TG技术在40~800 ℃温区研究了两配合物的热稳定性.由TG/DTG曲线分析可知, [Ho2(Ala)4(H2O)8]Cl6从80 ℃到479 ℃热分解分两步完成, [ErY(Ala)4(H2O)8](ClO4)6从120 ℃到430 ℃热分解分三步完成.  相似文献   

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Structural determinations of the magnesium(II) and barium(II) salts of pyromellitic acid (benzene‐1,2,4,5‐tetra­carboxyl­ic acid) are presented. Hexa­aqua­magnesium(II) benzene‐1,2,4,5‐tetra­carboxyl­ate(2−), [Mg(H2O)6](C10H4O8), (I), and penta­aqua­[benzene‐1,2,4,5‐tetra­carboxyl­ato(2−)]­barium(II), [Ba(C10H4O8)(H2O)5], (II), are both centrosymmetric and both possess a 1:1 metal–ligand ratio, but the two structures are found to differ in that the magnesium salt contains a hexaaqua cation and possesses only hydrogen‐bonding interactions between cations and anions, while the barium salt exhibits coordination of the carboxyl­ate ligand to the nine‐coordinate metal centre. In (I), both ions sit on a 2/m site symmetry, and in (II), the cation and anion are located on m and i site symmetries, respectively.  相似文献   

10.
In the title complexes the cis-benzenetrioxide acts as tridentate ligand, allowing for octahedral and unusual tetracapped trigonal prismatic coordination (TECTP).  相似文献   

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New Oxonium Bromochalcogenates(IV) — Synthesis, Structure, and Properties of [H3O][TeBr5] · 3 C4H8O2 and [H3O]2[SeBr6] Dark red crystals of the composition [H3O][TeBr5] · 3 C4H8O2 ( 1 ) were isolated from a saturated solution of TeBr4 in 1,4-dioxane containing a small amount of water. In this compound (space group P21/m, a = 8.922(4) Å, b = 13.204(7) Å, c = 9.853(5) Å, β = 91.82(4)° at 150 K) a square pyramidal [TeBr5]? anion has been isolated for the first time. The coordination sphere of the anion is completed to a distorted octahedron by weak interaction with a dioxane molecule of the cationic system. The [H3O]+ cations are connected to chains by dioxane molecules. At room temperature the compound is stable only in its mother liquor. Crystalline [H3O]2[SeBr6] ( 2 ) (space group Fm3m, a = 10.421(1) Å at 170 K) is a bromoselenous acid of high symmetry. The [H3O]+ ion is only weakly coordinated by Br atoms of the anion. The anions are isolated octahedral [SeBr6]2? units. The structure is isotypic to the K2[PtCl6] structure. Despite being a halogenochalcogen(IV) acid, 2 exhibits a remarkable thermal stability. Both oxonium compounds were characterized by single-crystal X-ray structure analyses. Vibrational spectra of 2 are reported.  相似文献   

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以硝酸铜和对氯苯氧乙酸为原料,合成了标题化合物[Cu(C8H6ClO3)2(H2O)2],并用元素分析仪、红外光谱仪、X射线单晶衍射仪表征了其组成和晶体结构.结果表明,所合成的晶体属三斜晶系,Pi空间群,a=0.51146(6)nm,b=0.70640(8)nm,c=1.326410(15)nm,a=81.7770(10)°,β=86.361(2)°,γ=76.3970(10)°,F(000)=239,Z=1;最终偏离因子R=0.0264,wR=0.0674.在配合物中,铜离子与来自两个对氯苯氧乙酸根的两个羧基氧原子、两个醚氧原子以及来自两个水分子的氧原子配位,形成变形八面体结构.  相似文献   

15.
Preparation and Crystal Structure of (CH3NH3)8[NdCl6][NdCl4(H20)2]2Cl3 (CH3NH3)8[NdCl6][NdCl4 (H2O)2]2Cl3 is for the first time prepared and investigated by X-ray, single crystal work. It crystallizes in the monoclinic system (space group C2/m, Z = 2) with a = 9.358(5), b = 17.424(9), c = 15.360(8) Å, β = 108.30(4)°. The structure contains besides isolated Cl? ions distorted [NdCl6]3? octahedra and [NdCl4(H2O)2]? chains.  相似文献   

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Conditions for the synthesis of the water-soluble lead thiosulfate complex Na6[Pb(S2O3)4] · 6H2O were determined. The complex synthesized was characterized by UV and IR spectroscopy and X-ray phase and thermal analyses. Thermolysis schemes were proposed on the basis of the IR and mass spectra of the thermal decomposition products.  相似文献   

18.
The structures of orthorhombic bis[pentaammineaquacobalt(III)] tetra‐μ2‐fluorido‐tetradecafluoridotrizirconium(IV) hexahydrate (space group Ibam), [Co(NH3)5(H2O)]2[Zr3F18]·6H2O, (I), and bis[hexaamminecobalt(III)] tetra‐μ2‐fluorido‐tetradecafluoridotrizirconium(IV) hexahydrate (space group Pnna), [Co(NH3)6]2[Zr3F18]·6H2O, (II), consist of complex [Co(NH3)x(H2O)y]3+ cations with either m [in (I)] or and 2 [in (II)] symmetry, [Zr3F18]6− anionic chains located on sites with 222 [in (I)] or 2 [in (II)] symmetry, and water molecules.  相似文献   

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Crystal structures of Cs4[Re6Te8(CN)6]·2H2O (1) and Ba2[Re6Te8(CN)6]· 12H2O (2) are determined. Crystals 1 are orthorhombic, a = 14,282(1), b = 12.910(1), c = 18.040(1) Å, Vcell = 3326.3(8) Å3, space group Pbcn, Z = 4, dcalc = 5.715 g/cm3, R(F) = 0.0482 for 3193 Fhkl > 4σ(F). Crystals 2 are triclinic, a = 9.671(3), b = 9.697(4), c = 11.039(4) Å, α = 89.86(3), β = 72.34(3), γ = 82.46(3)°, Vcell = 977.2(6) Å3, space group P1, Z = 1, dcalc = 4.733 g/cm3, R(F) = 0.0490 for 3226 Fhkl > 4σ(F). In both structures, the [Re6Te8(CN)6]4? anions form a distorted primitive cubic packing with distances between the centers 9.02-9.63 Å in 1 and 9.70-11.04 Å in 2. The Cs+ cations in 1 lie near the face centers of the cubes formed by the onions. In 2, cation pairs (Ba2+)2 bonded to two solvate water molecules are formed; the pairs lie at the centers of the anion cubes. In structures 1 and 2, there are shortened contacts between the tellurium atoms belonging to the neighboring anions (3.75-4.09 and 3.95-4.22 Å, respectively).  相似文献   

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