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1.
Three novel coordination polymers built of octahedral niobium cyanochloride clusters [Nb6Cl12(CN)6] and alkaline earth metal complexes have been prepared by reaction of aqueous solutions of (Me4N)4Nb6Cl18 and KCN with solutions of alkaline earth metal salts and 1,10-phenanthroline (phen) (1:2 molar ratio) in H2O/EtOH. The structures of [Ca(phen)2(H2O)3]2[Nb6Cl12(CN)6] x (phen)(EtOH)1.6 (1), [Ca(phen)2(H2O)2]2[Nb6Cl12(CN)6] x (phen)2 x 4H2O (2), and [Ba(phen)2(H2O)]2[Nb6Cl12(CN)6] (3) were determined by single-crystal X-ray diffraction. The three compounds were found to crystallize in the monoclinic system (space group Pn) with a = 11.5499(6) A, b = 17.5305(8) A, c = 21.784(1) A, beta = 100.877(1) degrees for 1; triclinic system (P1) with a = 12.609(4) A, b = 13.262(4) A, c = 16.645(5) A, alpha = 69.933(6) degrees, beta = 68.607(6) degrees, gamma = 63.522(5) degrees for 2; and a = 16.057(1) A, b = 16.063(1) A, c = 16.061(1) A, alpha = 86.830(1) degrees, beta = 64.380(1) degrees, gamma = 67.803(1) degrees for 3. Compounds 1 and 2 are built of cluster anions [Nb6Cl12(CN)6]4- trans-coordinated by two Ca2+ complexes via CN ligands to form neutral macromolecular units [Ca(phen)2(H2O)3]2[Nb6Cl12(CN)6] in 1 and [Ca(phen)2(H2O)2]2[Nb6Cl12(CN)6] in 2. Water of coordination and cyanide ligands form hydrogen bonded 3D and 2D frameworks for 1 and 2, respectively. The structure of 3 consists of [Nb6Cl12(CN)6]4- cluster anions and [Ba(phen)2(H2O)]2+ complexes linked through bridging cyanide ligands to form a neutral three-dimensional framework in which each barium complex is bound to three neighboring Nb6 clusters and each Nb6 cluster is linked to six Ba complexes. 相似文献
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We have investigated the possibility of altering the electronic configuration of the niobium oxochloride cluster compound Ti2Nb6Cl14O4 (I) by doping this material with monovalent cations that can fit into cavities present in its cluster framework. The doping of I with In+ and Tl+ ions resulted in the formation of MxTi2Nb6Cl14-xO4+x (M = In, x = 0.10, 0.20, 0.27; M = Tl, x = 0.10, 0.20) in which the M+ ions partially occupy these cavities. The crystal structure analysis indicated that the additional charge provided by M+ ions is compensated by substitution of chlorine by oxygen, which leads to the cluster electronic configuration being intact. Crystal data: In0.272Ti2Nb6Cl13.728O4.272, space group C2/c (No. 15), a = 12.679(2) A, b = 14.567(2) A, c = 12.632(3) A, beta = 95.26(2) degrees, Z = 4; Tl0.196Ti2Nb6Cl13.804O4.196, space group C2/c (no. 15), a = 12.732(1) A, b = 14.607(2) A, c = 12.662(2) A, beta = 95.28(1) degrees, Z = 4. 相似文献
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Structure and Electrochemical Study of Nb3Cl8 The compound Nb3Cl8 was synthesized from NbCl5 and niobium metal in a sealed quartz ampoule at 700 °C. Single crystals, obtained from LiCl melt were used for X‐ray structure determination (space group P 3 m1, Z = 2, lattice parameters a = b = 672.95(7) pm, c = 1223.2(2) pm (at 100 K), R1 = 0.029, wR2 = 0.064 for all independent reflections). Electrical resistivity measurements are reported. Electrochemical intercalation of lithium into the structure of Nb3Cl8 was studied. 相似文献
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(NH4)2[Mo6Cl14] · H2O ( 1 ) was prepared from reactions of MoCl2 in ethanol with aqueous NH4Cl solution. It crystallizes in the monoclinic space group I2/a (no. 15), Z = 4 with a = 912.3(1), b = 1491.2(2), c = 1724.8(2) pm, β = 92.25(1)°; R1 = 0.023 (based on F values) and wR2 = 0.059 (based on F2 values), for all measured X‐ray reflections. The structure of the cluster anion can be given as [(Mo6Cl)Cl]2– (i = inner, a = outer ligands). Thermal stability studies show that 1 loses crystal water followed by the loss of NH4Cl above 350 °C to yield MoCl2. The water‐free compound (NH4)2[Mo6Cl14] ( 2 ) was synthesized by solid state reaction of MoCl2 and NH4Cl in a sealed quartz ampoule at 270 °C. No single‐crystals could be obtained. Decompositions of 1 and 2 under nitrogen and argon exhibited the loss of NH4Cl at about 350 °C. Decomposition under NH3 resulted in the formation of MoN and Mo2N at 540 °C and 720 °C, respectively. 相似文献
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The first quaternary vanadium niobium compounds containing triangular Nb(3) clusters corresponding to the general formula, AVNb(3)Cl(11) (A = K, Rb, Cs, Tl), have been prepared in sealed quartz tubes from stoichiometric amounts of ACl (A = K, Rb, Cs), or Tl metal, VCl(3), Nb powder, and NbCl(5) heated at 740 degrees C. The compounds crystallize in the orthorhombic space group Pnma (No. 62). The crystal structures of the Rb and Tl members were determined by single-crystal X-ray diffraction techniques. Crystal data: a = 12.771(3) A, b = 6.811(2) A, c = 17.183(3) A, V = 1494.6(1) A(3), and Z = 4 for A = Rb; and a = 12.698(5) A, b = 6.798(3) A, c = 17.145(10) A, V = 1480.0(13) A(3), and Z = 4 for A = Tl. The crystal structure of AVNb(3)Cl(11) consists of triangular Nb(3)Cl(13) clusters (Nb-Nb = 2.826 A) connected to each other via four outer ligands to form infinite chains along the b-axis. The chains are connected by vanadium atoms located in an octahedral environment to form puckered sheets. The A(+) counterions are located between adjacent sheets and coordinate to twelve chlorine ligands in anticubeoctahedral geometry. Electronic structure calculations show bonding orbitals similar to those in Nb(3)Cl(8). Magnetic susceptibility measurements show paramagnetic Curie Weiss behavior. 相似文献
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KSbP2O8 crystallizes in the rhombohedral system, space group , with a = 4.7623(4) Å, c = 25.409(4)Å, and Z = 3. The structure was determined from 487 reflexions collected on a NONIUS CAD4 automatic diffractometer with MoK?α radiation. The final R index and weighted Rw index are 0.030 and 0.038, respectively. This structure is built up from layers of SbO6 octahedra and PO4 tetrahedra sharing corners. These (SbP2O?8)n layers are very similar to the (ZrP2O2?8)n layers in the well-known α-ZrP compound. 相似文献
9.
Christopher M. MacNeill Cynthia S. Day Sergio A. Gamboa Abdessadek Lachgar Ronald E. Noftle 《Journal of chemical crystallography》2010,40(3):222-230
Abstract
Two new lanthanide thiophenedicarboxylate-based metal-organic frameworks with the formulas La2(2,5-TDC)3(DMF)2H2O DMF (1) and Gd2(2,5-TDC)3(DMF)2H2O (2) (2,5-TDC = 2,5-thiophenedicarboxylic acid; DMF = N,N′-dimethylformamide), have been synthesized by two different methods (solvothermal and reflux). The synthesis of these materials from metal nitrate hydrates with 2,5-TDC as the organic linker in DMF/n-propanol afforded two rigid non-interpenetrating frameworks with coordinated solvent molecules (DMF and H2O) occupying the channels. Compound (1) crystallizes in an orthorhombic space group Pna21 with Z = 4, a = 17.434(4) ?, b = 11.227(3) ?, c = 17.980(4) ? and V = 3,519.0(15) ?3. Compound (2) crystallizes in a monoclinic P21/n space group with Z = 4, a = 17.5387(17) ?, b = 10.8038(11) ?, c = 17.7283(18) ?, β = 104.793(2) and V = 3,247.9(6) ?3. Powder X-ray diffraction, thermogravimetric analysis and infrared spectroscopy of (1) and (2) are presented. 相似文献10.
Synthesis and crystal structure of indium arsenate and phosphate dihydrates with variscite and metavariscite structure types 总被引:1,自引:0,他引:1
XueJiao Tang Maria J. Gentiletti Abdessadek Lachgar 《Journal of chemical crystallography》2001,31(1):45-50
The hydrothermal synthesis, crystal structure analysis, and spectroscopic studies of InPO4·2H2O (1) and InAsO4·2H2O (2) are reported. Compound 1 is isomorphic with metavariscite: monoclinic P21/n (No. 14), a = 5.4551(3) Å, b = 10.2293(4) Å, c = 8.8861(3) Å, = 91.489(4)°, Z = 4, and compound 2 is isomorphic with variscite: orthorhombic Pbca (No. 61), a = 10.478(1) Å, b = 9.0998(8) Å, c = 10.345(1) Å, Z = 8. Their three-dimensional frameworks are built of corner sharing InO4(H2O)2 octahedra and MO4 (M = P5+ or As5+) tetrahedra. The water molecules in both compounds have different environments and are involved in different types of hydrogen bonding. Infrared spectroscopy indicates that water molecules are true H2O species. 相似文献