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The crystal structures of two new diphosphates, sodium hexamanganese bis­(diphosphate) triphosphate, NaMn6(P2O7)2(P3O10), and potassium hexacadmium bis­(diphosphate) triphosphate, KCd6(P2O7)2(P3O10), confirm the rigidity of the M6(P2O7)2(P3O10) matrix (M is Mn or Cd) and the relatively fixed dimensions of the tunnels extending in the a direction of the unit cell. The compounds are isomorphous; the P2O74? anion and the alkali metal cations lie on mirror planes. Bond‐valence analysis of the bonding details of the atoms found within the tunnels permits a prediction of the conductivity.  相似文献   

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Kubatko KA  Burns PC 《Inorganic chemistry》2006,45(25):10277-10281
Two novel U6+ compounds, Sr5(UO2)20(UO6)2O16(OH)6(H2O)6 (SrFm) and Cs(UO2)9U3O16(OH)5 (CsFm), have been synthesized by mild hydrothermal reactions. The structures of SrFm (orthorhombic, C2221, a = 11.668(1), b = 21.065 (3), c = 13.273 A, V = 3532.5(1) A3, Z = 2) and CsFm (trigonal, R3c, a = 11.395(2), c = 43.722(7) A, V = 4916.7(1) A3, Z = 6) are rare examples of uranyl compounds that contain cation-cation interactions where an O atom of one uranyl ion is directly linked to another uranyl ion. Both structures are complex frameworks. SrFm contains sheets of polyhedra that are linked through cation-cation interactions with uranyl ions located between the sheets. CsFm possesses an unusually complex framework of vertex- and edge-sharing U6+ polyhedra that incorporates cation-cation interactions.  相似文献   

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Geometrical and topological analysis of zeolite crystal structures having a tetrahedral framework of the cancrinite (CAN) type, namely, (CAN) Na8(Al6Ge6O24)Ge(OH)6(H2O)2 (acentric space group P63, hP64, Na-CAN) and Cs2Na6(Al6Ge6O24)Ge(OH)6 (P63, hP52, CsNa-CAN), is carried out with the use of computer techniques (the TOPOS 4.0 program package). An AT 6 hexapolyhedral precursor nanocluster centered with a template cation A (Na, Cs) is identified. The topological type of a two-dimensional (2D) crystalforming T-net 4.6.12, which corresponds to a uninodal semiregular Shubnikov net, is recognized. The full 3D reconstruction of crystal structure self-assembly is performed as follows: precursor nanocluster → primary chain → microlayer → microframework → … framework. The symmetry of an AT6 precursor nanocluster is described by point group 3; the symmetry axis passes through the center of the nanocluster and cation A. The coordination number (CN) of a precursor nanocluster, which characterizes the nanocluster stacking in the macrostructure, is six. In both structures, six Na atoms and a Ge(OH)6 polyhedral species are spacers filling the voids between AT 6 precursor nanoclusters. The Ge(OH)6 polyhedral species is characterized by four and two orientationally allowed positions in Na-CAN and CsNa-CAN, respectively. The minimal number of suprapolyhedral AT 6 precursor nanoclusters required for the 3D microframework to form is 16; that is, 96 tetrahedra are involved in microframework self-assembly.  相似文献   

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Synthetic methods for several novel phosphoramidate compounds containing the P(O)NHC(O) bifunctional group were developed. These compounds with the general formula R1C(O)NHP(O)(N(R2)(CH2C6H5))2, where R1 = CCl2H, p-ClC6H4, p-BrC6H4, o-FC6H4 and R2 = hydrogen, methyl, benzyl, were characterized by several spectroscopic methods and analytical techniques. The effects of phosphorus substituents on the rotation rate around the P–Namine bond were also investigated. 1H NMR study of the synthesized compounds demonstrated that the presence of bulky groups attached to the phosphorus center and electron withdrawing groups in the amide moiety lead to large chemical-shift non-equivalence (ΔδH) of diastereotopic methylene protons. The crystal structures of CCl2HC(O)NHP(O)(NCH3(CH2C6H5))2, p-ClC6H4C(O)NHP(O)(NCH3(CH2C6H5))2, CCl2HC(O)NHP(O)(N(CH2C6H5)2)2 and p-BrC6H4C(O)NHP(O)(N(CH2C6H5)2)2 were determined by X-ray crystallography using single crystals. The coordination around the phosphorus center in these compounds is best described as distorted tetrahedral and the P(O) and C(O) groups are anti with respect to each other. In the compound Br-C6H4C(O)NHP(O)(N(CH2C6H5)2)2 (with two independent molecules in the unit cell), two conformers are connected to each other via two different N–H?O hydrogen bonds forming a non-centrosymmetric dimer. In the crystalline lattice of other compounds, the molecules form centrosymmetric dimers via pairs of same N–H?O hydrogen bonds. The structure of CCl2HC(O)NHP(O)(N(CH2C6H5)2)2 reveals an unusual intramolecular interaction between the oxygen of CO group and amine nitrogen.  相似文献   

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Crystal Chemistry Examinations of the Phases: (I) Zn(V0.12Nb0.88)2O6, (II) Zn(V0.28Ta0.72)2O6, and (III) Zn(Nb0.58Ta0.42)2O6 Single crystals of the quaternary phases ( I ), ( II ), and ( III ) were prepared by high temperature technique and investigated by X-ray single crystal methods. Phase ( I ) crystallizes in the columbite Structure. Phase ( II ) deviates from the ternary compounds (ZnV2O6, ZnTa2O6) and appears in trirutile type. In phase ( III ) the octahedra arrangement of the tri-α-PbO2 Structure is realized.  相似文献   

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Tetraphenyl Imidodiphosphate as Ligand in Fluoro Complexes. 3. Fluoro Complexes of Niobium, Tantalum, and Antimony Tetraphenyl imidodiphosphate forms with NbF5, TaF5, and SbF5 the addition complexes MF5 · LH and (MF5)2(μ-LH). The imidodiphosphate acts in the latter as bidentately bridging ligand. Furtheron, it reacts with NbF5 and TaF5 by replacing fluoride forming tetrafloro and trifluoro complexes: [MF4(μ-L)]2 and MF32-L)(OPh) or μ-O[MF32-L)]2, resp., (M ? Nb, Ta). SbF5 does not form substitution complexes. The constitution and conformation of the complexes have been concluded from n.m.r. spectroscopic data.  相似文献   

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A hydrothermal approach employing an amine as reducing agent enables synthesis of an analogue of the arsenato(iii)-oxovanadate {V(15)As(6)}, representing the first systematic variation of this intensely studied magnetic system.  相似文献   

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《Polyhedron》2007,26(9-11):2235-2242
The ligand exchange reaction between Mn(OC(O)CH3)2 and benzoic acid under solvothermal conditions in toluene at 110 °C yields colorless crystals of {Mn5(OC(O)CH3)6(OC(O)C6H5)4} (1). The asymmetric unit of this complex is Mn2.5(OC(O)CH3)3(OC(O)C6H5)2 with each of the three different Mn(II) atoms in 6-fold coordination and one of the benzoate ligands exhibiting the rare μ3-symmetric bridging mode (O–Mn–O angle = 57°). The structure consists of edge-shared Mn12 loops arranged in a honeycomb-like 2D sheet with the acetate ligands displaced slightly out of the plane. The sheets are spaced at 12 Å and linked into a 3D network via weak intersheet interactions. Magnetic susceptibility characterization of 1 indicates antiferromagnetic exchange with a Weiss constant of −165 K and a transition toward ferromagnetic exchange below 10 K corroborated with a finite imaginary component in the variable temperature susceptibility data.  相似文献   

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王崇臣  王鹏 《化学研究》2008,19(4):9-13
用NiCl2·6H2O,2,2'-联吡啶(bpy),NH4VO3,WO3在443K下通过水热反应法得到了两种多钒酸镍配合物Ni(bpy)(H2O)(V2O6)(1)和[Ni(bpy)2]2(V6O17)(2).单晶X射线衍射结果表明化合物(1)属于正交晶系,空间群为Pcα2(1),晶胞参数为0=0.91704(18)nm,b=1.0519(2)nm,c=1.4336(3)nm,V=1.3830(5)nm^3,Z=4;化合物(2)属于单斜晶系,空间群为P2(1)/c,晶胞参数为α=1.5467(3)nm,b=1.4740(3)nm,c=1.0457(2)nm,β=91.99(3)°,V=2.3826(8)nm^3,Z=4.化合物(1)由2,2’-联吡啶修饰的二维[Ni(V2O6)(H2O)]∞电中性层构成,而化合物(2)则由2,2'-联吡啶修饰的、呈正弦波浪状的[Ni:(V6O17)]∞二维电中性层构成.  相似文献   

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《Polyhedron》2002,21(12-13):1299-1304
The crystal structure of a trinuclear iron monoiodoacetate complex was determined. Although it has been incorrectly characterized as [Fe3O(O2CCH2I)6(H2O)3], the correct chemical formula turned out to be [Fe(III)2Fe(II)O(O2CCH2I)6(H2O)3]-[Fe(III)3O(O2CCH2I)6(H2O)3]I (1). The two kinds of Fe3O molecules (Fe(III)2Fe(II)O and Fe(III)3O) are crystallographically indistinguishable. All the Fe atoms are crystallographically equivalent because of a crystallographic threefold symmetry. Heat capacities of 1 seem to exhibit no thermal anomaly in the temperature range 5.5–309 K, although the valence detrapping phenomenon has been observed in this temperature range. This fact indicates that the valence-detrapping phenomenon in 1 occurs without any phase transition, leading 1 to a glassy state, probably because the crystal of 1 is just like a solid solution of distorted mixed-valence Fe(III)2Fe(II)O molecules and permanently undistorted Fe(III)3O molecules which may act as an inhibitor for a cooperative valence-trapping.  相似文献   

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