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1.
The synthesis and crystal structure of Cs3Mn[Nb6Cl9O3(CN)6]0.6H2O are described in this work. It crystallizes in the cubic system (space group Fm-3m; a=15.708(5) Å) and is characterized by a static orientational disorder of the [Nb6Cl9O3(CN)6]5− cluster units. It results in a framework structurally related to that encountered in the well known Prussian Blue family prepared for different hexacyanometallates. The charge of the framework is compensated by cesium cations that are located in the tetrahedral cavities of the c.f.c. lattice of units along with water molecules. We will evidence the features that act in the crystallization of solid state compounds built up from ordered or disordered units as well as the influence of orientational disorder on interatomic distances obtained from single-crystal X-ray diffraction investigations.  相似文献   

2.
A new cesium uranyl niobate, Cs9[(UO2)8O4(NbO5)(Nb2O8)2] or Cs9U8Nb5O41 has been synthesized by high-temperature solid-state reaction, using a mixture of U3O8, Cs2CO3 and Nb2O5. Single crystals were obtained by incongruent melting of a starting mixture with metallic ratio=Cs/U/Nb=1/1/1. The crystal structure of the title compound was determined from single crystal X-ray diffraction data, and solved in the monoclinic system with the following crystallographic data: a=16.729(2) Å, b=14.933(2) Å, c=20.155(2) Å β=110.59(1)°, P21/c space group and Z=4. The crystal structure was refined to agreement factors R1=0.049 and wR2=0.089, calculated for 4660 unique observed reflections with I?2σ(I), collected on a BRUKER AXS diffractometer with MoKα radiation and a CCD detector.In this structure the UO7 uranyl pentagonal bipyramids are connected by sharing edges and corners to form a uranyl layer corresponding to a new anion-sheet topology, and creating triangular, rectangular and square vacant sites. The two last sites are occupied by Nb2O8 entities and NbO5 square pyramids, respectively, to form infinite uranyl niobate sheets stacking along the [010] direction. The Nb2O8 entities result from two edge-shared NbO5 square pyramids. The Cs+ cations are localized between layers and ensured the cohesion of the structure.The cesium cation mobility between the uranyl niobate sheets was studied by electrical measurements. The conductivity obeys the Arrhenius law in all the studied temperature domains. The observed low conductivity values with high activation energy may be explained by the strong connection of the Cs+ cations to the infinite uranyl niobate layers and by the high density of these cations in the interlayer space without vacant site.Infrared spectroscopy investigated at room temperature in the frequency range 400-4000 cm−1, showed some characteristic bands of uranyl ion and niobium polyhedra.  相似文献   

3.
A novel heteropoly compound, containing two kinds of coordinated cations, [K(H2O)2Ni(H2O)6]2[V10O28], has been synthesized through routine process and characterized by elemental analyses, IR, 51V NMR and single crystal X-ray diffraction. It crystallizes in the triclinic system, space group P1 with a=0.87382(17) nm, b=1.075 4(2) nm, c=1.111 1(2) nm, α=65.10(3)°, β=75.01(3)°, γ=70.63(3)°, V=0.884 8(3) nm3 and Z=1. The X-ray analysis reveals that the two kinds of coordinated cations are linked by three shared coordinated water molecules, and K+ cations coordinate with ten oxygen atoms: five of which come from V10O286- anion, the other five from water molecules. The title compound exhibits extended 2D array building up of V10O286- groups connected by ten-coordinated K+ cations. The hexahydrated nickel cations Ni(H2O)62+ lie in neat apposition to three adjacent V10O286- clusters. CSD: 413271.  相似文献   

4.
The compound (NpO2)2(SO4)(H2O)4 was synthesized by evaporation of a Np5+ sulfate solution. The crystal structure was determined using single crystal X-ray diffraction and refined to an R1=0.0310. (NpO2)2(SO4)(H2O)4 crystallizes in triclinic space group P-1, a=8.1102(7) Å, b=8.7506(7) Å, c=16.234(1) Å, α=90.242(2)°, β=92.855(2)°, γ=113.067(2)°, V=1058.3(2) Å3, and Z=2. The structure contains neptunyl pentagonal bipyramids that share vertices through cation-cation interactions to form a sheet or cationic net. The sheet is decorated on each side by vertex sharing with sulfate tetrahedra, and adjacent sheets are linked together through hydrogen bonding. A graphical representation of (NpO2)2(SO4)(H2O)4 was constructed to facilitate the structural comparison to similar Np5+ compounds. The prevalence of the cationic nets in neptunyl sulfate compounds related to the overall stability of the structure is also discussed.  相似文献   

5.
Two new mixed-halide zirconium cluster phases have been synthesized by solid-state reactions in sealed tantalum containers from the Zr(IV) halides, elemental Zr and B, and NaI or CsCl, respectively. Single-crystal X-ray data were used to determine the crystal structures of Na[(Zr6B)Cl3.9I10.1], and Cs[(Zr6B)Cl2.2I11.8]. Both phases crystallize in a stuffed version of the [Nb6Cl14] structure type, orthorhombic, space group Cmca (Na[(Zr6B)Cl3.87(5)I10.13]: a=15.787(2) Å, b=14.109(2) Å, c=12.505(2) Å, Z=4, R1(F)=0.0322 and wR2(F2)=0.0842; Cs[(Zr6B)Cl2.16(5)I11.84]: a=15.696(4) Å, b=14.156(4) Å, c=12.811(4) Å, Z=4, R1(F)=0.0404 and wR2(F2)=0.1031). This structure type is constructed of clusters which contain centered (Zr6Z) octahedra of the type [(Zr6Z)X12iX6a] with Z=B and X=Cl and/or I. In both structures, chlorine and iodine atoms are randomly (to X-rays) distributed on the inner non-cluster-interconnecting ligand positions, whereas those sites which bridge metal octahedra are solely occupied by iodine. The phase widths for both phases have been found to cover 0x4 for AI[(Zr6B)ClxI14−x]. Whereas the sodium cations in Na[(Zr6B)ClxI14−x] occupy 25% of a site which is octahedrally surrounded by halogen atoms, the larger cations in the cesium-containing phase occupy a 12-coordinate site within the cluster network.  相似文献   

6.
A new series of quaternary niobium chloride cluster compounds corresponding to the general formula, A2VNb6Cl18 (A=Rb, Tl or In), has been prepared in sealed quartz tubes from a mixture containing NbCl5, Nb, VCl3 and RbCl, or In or Tl metal by solid state reactions at 750°C. The structure of Tl2VNb6Cl18 was determined using single-crystal X-ray diffraction: Crystal data: rhombohedral, (No. 148), a=9.1122(17), c=25.178(7) Å, V=1810.5(7) Å3 and Z=3. The full-matrix least-squares refinement against F2 converged to R1=0.0515, wR2=0.1104 (all data). The structure consists of discrete octahedral cluster units, [Nb6Cli12Cla6]4− linked by V2+ and A+ cations, located in a 6-coordinated octahedral and 12-coordinated anticubeoctahedral chloride environment, respectively. The intra-cluster bond lengths indicate 16 valence electrons per cluster. Magnetic susceptibility studies show paramagnetic behavior with a magnetic moment of 3.37 μB per formula unit. Electrical resistivity measurements indicate a semiconducting behavior.  相似文献   

7.
Two novel metal sulfur chlorides - Zn6S5Cl2 (1) and Hg3ZnS2Cl4 (2) - were obtained by solid-state reactions and structurally characterized by single-crystal X-ray diffraction. Compound 1 is characteristic of a 1-D tunnel-like structure, which connects to each other to construct a 3-D framework with the chlorine atoms locating at the voids. Compound 2 crystallizes in the acentric space group P63mc of the hexagonal system. Compound 2 features a 2-D layered motif, which is composed by the interconnected 12-membered Hg6S3Cl3 rings with chair-like conformation. There are ZnSCl3 tetrahedra located between the layers, yielding a sandwich-like structure. TG-DTA measurement shows that compound 1 is thermally stable up to 220 °C. Optical absorption spectra reveal the presence of sharp optical gap of 2.71 and 2.65 eV for 1 and 2, respectively.  相似文献   

8.
Reaction of [MoOCl5]2− with in situ generated H2Se under hydrothermal conditions (4M HCl, 140 °C) leads to reduction of Mo(V) to Mo(IV) with the formation of a triangular cluster Mo33-Se)(μ-O)34+ in high yield. It is present in HCl solutions as aqua chlorocomplex [Mo33-Se)(μ-O)3(H2O)6Cl3]+ which was isolated and structurally characterized as supramolecular adduct with cucurbit[6]uril (CB[6]), {[Mo33-Se)(μ-O)3(H2O)6Cl3]2CB[6]}Cl2·15H2O. Dedicated to Professor Dieter Fenske on the Occasion of his 65th Birthday  相似文献   

9.
许多化学工作者对单齿膦配体(PPh3,PBun3,PEt2Ph,P(OEt)3,P(OC6H5)3)与母体簇合物FeCo2(CO)9(μ3-S)的取代反应进行过详细研究[1-3],但对双齿膦配体与母体簇合物的取代反应研究报导较少.Aime[4]合成了含双齿膦配体的簇合物FeCo2(CO)7(μ3-S)(Ph2PCH2PPh2),并用13CNMR和IR光谱方法对其结构进行了表征.到目前为止,含双齿膦配体的该类簇合物的晶体与分子结构还未见报导.RosannaRossetti[2]通过研究母体簇合物与…  相似文献   

10.
Tetrahydroborate enclathrated sodalites with gallosilicate and aluminogermanate host framework were synthesized under mild hydrothermal conditions and characterized by X-ray powder diffraction and IR spectroscopy. Crystal structures were refined in the space group P-43n from X-ray powder data using the Rietveld method. Na8[GaSiO4]6(BH4)2: a=895.90(1) pm, V=0.71909(3)×10−6 nm3, RP=0.074, RB=0.022, Na8[AlGeO4]6(BH4)2: a=905.89(2) pm, V=0.74340(6)×10−6 nm3, RP=0.082, RB=0.026. The tetrahedral framework T-atoms are completely ordered in each case and the boron atoms are located at the centre of the sodalite cages. The hydrogen atoms of the enclathrated anions were refined on x, x, x positions, restraining them to boron-hydrogen distances of 116.8 pm as found in NaBD4.The IR-absorption spectra of the novel phases show the typical bands of the tetrahedral group as found in the spectrum of pure sodium boron hydride.The new sodalites are discussed as interesting -containing model compounds which could release pure hydrogen.  相似文献   

11.
The hydrothermal reactions of vanadium oxide starting materials with divalent transition metal cations in the presence of nitrogen donor chelating ligands yield the bimetallic cluster complexes with the formulae [{Cd(phen2)2V4O12]·5H2O (1) and [Ni(phen)3]2[V4O12]·17.5H2O (2). Crystal data: C48H52Cd2N8O22V4 (1), triclinic. a=10.3366(10), b=11.320(3), c=13.268(3) Å, =103.888(17)°, β=92.256(15)°, γ=107.444(14)°, Z=1; C72H131N12Ni2O29.5V4 (2), triclinic. a=12.305(3), b=13.172(6), c=15.133(4), =79.05(3)°, β=76.09(2)°, γ=74.66(3)°, Z=1. Data were collected on a Siemens P4 four-circle diffractometer at 293 K in the range 1.59° <θ<26.02° and 2.01°<θ<25.01° using the ω-scan technique, respectively. The structure of 1 consists of a [V4O12]4− cluster covalently attached to two {Cd(phen)2}2+ fragments, in which the [V4O12]4− cluster adopts a chair-like configuration. In the structure of 2, the [V4O12]4− cluster is isolated. And the complex formed a layer structure via hydrogen bonds between the [V4O12]4− unit and crystallization water molecules.  相似文献   

12.
Two new niobium phosphates were synthesized and their crystal structures determined from single-crystal X-ray data. [NbOF(PO4)](N2C5H7) (1) (monoclinic, space group P21/c, a=11.442(1), b=9.1983(7), c=9.1696(8) Å, β=109.94(1)°) has a layered structure and is the first example of a negatively charged NbOF(PO4) layer analogous to the MO(H2O)PO4 (M=V, Nb) layers. The layer charge is compensated by interlayer 4-aminopyridnium cations that adopt an unusual arrangement as a consequence of H-bonding and π-π interactions. The interlayer aminopyridnium cations can be exchanged with alkylammonium ions which form bilayers inclined at ∼65° to the NbOF(PO4) layer. [(Nb0.9V1.1)O2(PO4)2(H2PO4)] (N2C2H10) (2) (orthorhombic, space group Pbca, a=15.821(2),b=9.0295(9),c=18.301(2) Å) has a disordered three-dimensional structure based on NbO(PO4) layers cross-linked by phosphate tetrahedra, and has a similar structure to the known vanadium analog [V2O2(PO4)2(H2PO4)] (N2C2H10).  相似文献   

13.
A new sodium hydroxygallophosphate, Na3Ga4O(OH)(H2O)(PO4)4·H2O, has been prepared by hydrothermal synthesis. Its structure has been determined from a single-crystal X-ray diffraction study. It crystallizes in the P21/c space group with the cell parameters a=9.445(2) Å, b=9.028(1) Å, c=19.209(3) Å, β=102.08(2), V=1603.4(4) Å3. Its three-dimensional framework can be described from PO4 monophosphate groups sharing their apices with original Ga4O16(OH)(H2O) tetrameric building units, which result from the assembly of one GaO4 tetrahedron, one GaO5 trigonal bipyramid and two octahedra: GaO5(OH) and GaO4(OH)(H2O). The sodium cations and one water molecule are located in tunnels running along b.  相似文献   

14.
Three new uranyl tungstates, A8[(UO2)4(WO4)4(WO5)2] (A=Rb (1), Cs (2)), and Rb6[(UO2)2O(WO4)4] (3), were prepared by high-temperature solid-state reactions and their structures were solved by direct methods on twinned crystals, refined to R1=0.050, 0.042, and 0.052 for 1, 2, and 3, respectively. Compounds 1 and 2 are isostructural, monoclinic P21/n, (1): a=11.100(7), b=13.161(9), , β=90.033(13)°, , Z=8 and (2): , , , β=89.988(2)°, , Z=8. There are four symmetrically independent U6+ sites that form linear uranyl [O=U=O]2+ cations with rather distorted coordination in their equatorial planes. There are six W positions: W(1) and W(2) have square-pyramidal coordination (WO5), whereas W(3), W(4), W(5), and W(6) are tetrahedrally coordinated. The structures are based upon a novel type of one-dimensional (1D) [(UO2)4(WO4)4(WO5)2]4− chains, consisting of WU4O25 pentamers linked by WO4 tetrahedra and WO5 square pyramids. The chains run parallel to the a-axis and are arranged in modulated pseudo-2D-layers parallel to (0 1 0). The A+ cations are in the interlayer space between adjacent pseudo-layers and provide a 3D integrity of the structures. Compounds 1 and 2 are the first uranyl tungstates with 2/3 of W atoms in tetrahedral coordination. Such a high concentration of low-coordinated W6+ cations is probably responsible for the 1D character of the uranyl tungstate units. The compound 3 is triclinic, Pa=10.188(2), b=13.110(2), , α=97.853(3), β=96.573(3), γ=103.894(3)°, , Z=4. There are four U positions in the structure with a typical coordination of a pentagonal bipyramid that contain uranyl ions, UO22+, as apical axes. Among eight W sites, the W(1), W(2), W(3), W(4), W(5), and W(6) atoms are tetrahedrally coordinated, whereas the W(7) and W(8) cations have distorted fivefold coordination. The structure contains chains of composition [(UO2)2O(WO4)4]6− composed of UO7 pentagonal bipyramids and W polyhedra. The chains involve dimers of UO7 pentagonal bipyramids that share common O atoms. The dimers are linked into chains by sharing corners with WO4 tetrahedra. The chains are parallel to [−101] and are arranged in layers that are parallel to (1 1 1). The Rb+ cations provide linkage of the chains into a 3D structure. The compound 1 has many structural and chemical similarities to its molybdate analog, Rb6[(UO2)2O(MoO4)4]. However, the compounds are not isostructural. Due to the tendency of the W6+ cations to have higher-than-fourfold coordination, part of the W sites adopt distorted fivefold coordination, whereas all Mo atoms in the Mo compound are tetrahedrally coordinated. Distribution of the WO5 configurations along the chain extension does not conform to its ‘typical’ periodicity. As a result, both the chain identity period and the unit-cell volume are doubled in comparison to the Mo analog, which leads to a new structure type.  相似文献   

15.
New uranyl vanadates A3(UO2)7(VO4)5O (M=Li (1), Na (2), Ag (3)) have been synthesized by solid-state reaction and their structures determined from single-crystal X-ray diffraction data for 1 and 3. The tetragonal structure results of an alternation of two types of sheets denoted S for 2[UO2(VO4)2]4− and D for 2[(UO2)2(VO4)3]5− built from UO6 square bipyramids and connected through VO4 tetrahedra to 1[U(3)O5-U(4)O5]8− infinite chains of edge-shared U(3)O7 and U(4)O7 pentagonal bipyramids alternatively parallel to a- and b-axis to construct a three-dimensional uranyl vanadate arrangement. It is noticeable that similar [UO5]4− chains are connected only by S-type sheets in A2(UO2)3(VO4)2O and by D-type sheets in A(UO2)4(VO4)3, thus A3(UO2)7(VO4)5O appears as an intergrowth structure between the two previously reported series. The mobility of the monovalent ion in the mutually perpendicular channels created in the three-dimensional arrangement is correlated to the occupation rate of the sites and by the geometry of the different sites occupied by either Na, Ag or Li. Crystallographic data: 293 K, Bruker X8-APEX2 X-ray diffractometer equipped with a 4 K CCD detector, MoKα, λ=0.71073 Å, tetragonal symmetry, space group Pm2, Z=1, full-matrix least-squares refinement on the basis of F2; 1,a=7.2794(9) Å, c=14.514(4) Å, R1=0.021 and wR2=0.048 for 62 parameters with 782 independent reflections with I?2σ(I); 3, a=7.2373(3) Å, c=14.7973(15) Å, R1=0.041 and wR2=0.085 for 60 parameters with 1066 independent reflections with I?2σ(I).  相似文献   

16.
Six new isostructural A2(Mo4Sb2O18) (A=Y, La, Nd, Sm, Gd and Dy) compounds have been synthesized by solid-state reactions and characterized by single crystal X-ray diffraction and spectroscopic techniques. They crystallize in C2/c space group with 4 formula units and contain A3+ cations and discrete centrosymmetric anionic (Mo4Sb2O18)6− aggregates, made of tetrahedral MoO4 and disphenoidal SbO4 moieties. They exhibit characteristic Sb3+ photoluminescence.  相似文献   

17.
Three new thiogermanates (enH)4Ge2S6 (1) and [M(en)3]2Ge2S6 (M=Mn (2), Ni (3); en=ethylenediamine) were synthesized using GeO2 and S8 as starting materials in molar ratio of 1:0.5 under solvothermal conditions. These compounds suggest that the dimeric [Ge2S6]4− anion is likely to be the main germanium-containing species in en system and it also might be preferred as counter anions by the transition metal complex cations in crystallization. The cations of [Mn(en)3]2+ and [Ni(en)3]2+ are even better mineralizers than the protonated amine of [enH]+. The crystal systems of [Ge2S6]4− compounds are related to entities of cations and intermolecular reactions between cations and [Ge2S6]4− anions. The compounds remove ethylenediamine and H2S molecules in multi steps when being heated under nitrogen stream.  相似文献   

18.
Two zinc phosphates (ZnPO), [H2(N2C9H20)]·[Zn(H2PO4)4] (I) and [H2(N2C9H20)]2·[Zn2(HPO4)3(H2PO4)2]·H2O (II), are synthesized under hydrothermal conditions using 4-amino-2.2.6.6-tetramethylpiperidine as organic template. I crystallizes in space group with , , , α=92.57(1)°, β=89.76(1)°, γ=102.16(2)°, and Z=2. Its structure, refined to R=0.029 and Rw=0.076 for 4279 independent reflections, consists of [Zn(H2PO4)4]2− clusters held together through strong hydrogen bonds to form pseudo-layers between which the doubly protonated amine molecules are inserted. II is monoclinic, C2, with , , , β=103.72(5)°, and Z=4 (R=0.079, Rw=0.268, 2477 independent reflections). The structure of II consists of [Zn2(HPO4)3(H2PO4)2]4− inorganic (2D) layers built up from vertex-sharing [ZnO4] and [(H2/H)PO4] tetrahedra. Organic cations and water molecules ensure the connection between these layers via hydrogen bonds. It is shown that numerous (1D), (2D), e.g., [H2(N2C9H20)]2·[Zn2(HPO4)3(H2PO4)2]·H2O, and (3D) (ZnPO) result from the condensation of the [Zn(H2PO4)4]2− clusters.  相似文献   

19.
The organic-inorganic hybrid materials vanadium oxide [VIVO2(phen)2]·6H2O (1) and [(2,2′-bipy)2VVO2](H2BO3)·3H2O (2) have been conventional and hydrothermal synthesized and characterized by single crystal X-ray diffraction, elemental analyses, respectively. Although the method and the ligand had been used in the syntheses of the compounds (1) and (2) are different, they almost possess similar structure. They all exhibit the distorted octahedral [VO2N4] unit with organonitrogen donors of the phen and 2,2′-bipy ligands, respectively, which coordinated directly to the vanadium oxide framework. And they are both non-mixed-valence complexes. But the compound (1) is isolated, and the compound (2) consists of a cation of [(2,2′-bipy)2VVO2]+ and an anion of (H2BO3). So the valence of vanadium of (1) and (2) are tetravalence and pentavalence, respectively. Meanwhile it is noteworthy that π-π stacking interaction between adjacent phen and 2,2′-bipy groups in compounds 1 and 2 also play a significant role in stabilization of the structure. Thus, the structure of [VIVO2(phen)2]·6H2O and [(2,2′-bipy)2VVO2](H2BO3)·3H2O are both further extended into interesting three-dimensional supramolecular. Crystal data: (1) Triclinic, a=8.481(4), b=12.097(5), and α=66.32(2), β=82.97(3), and γ=82.59(4)°, Z=2, R1=0.0685, wR2=0.1522. (2) Triclinic, a=6.643(13), b=11.794(2), and α=101.39(3), β=101.59(3), and γ=97.15(3)°, Z=2, R1=0.0736, wR2=0.1998.  相似文献   

20.
Crystallization from a ThBr4/DMSO/(Et4N)2Mo3S7Br6 mixture in benzonitrile gave [Th2(µ-SO4)2×(DMSO)12]{[Mo3S7Br5(DMSO)]Br}2·2DMSO·PhCN. The complex has an ionic structure. In the [Th2(µ-SO4)2(DMSO)12]4+ centrosymmetric binuclear cation, the metal atoms are bound by two sulfate bridges and are coordinated by DMSO oxygen atoms, the coordination polyhedron of thorium(IV) being a tricapped trigonal prism (c.n. 9). The [Mo3S7Br5(DMSO)]cluster anion and the bromide ion form an ion pair with Sax...Br short contacts, and the DMSO molecule is coordinated to one of the molybdenum atoms via the oxygen atom. The voids of the structure are filled with DMSO and PhCN solvate molecules, the latter being disordered over two positions related by an inversion center.Original Russian Text Copyright © 2004 by M. N. Sokolov, O. A. Gerasko, S. F. Solodovnikov, and V. P. FedinTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 516–521, May–June 2004.  相似文献   

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