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1.
<正> The compound Ni2Nb2Te4 crystallizes in orthorhombic system,space group Pma2 with cell dimensions a = 7.955(1),b=6.258(1),c=7.202(2)A,and Z=2.X-ray structural determination showed the non-molecular 2-dimensional character of the title compound. In each structural unit, the two Ni and two Nb atoms form a rhombic plane with four Ni-Nb bonds (average 2.675 A) and one Ni-Ni bond (2.536 A) and there exists no Nb-Nb interaction. The distorted tetrahedral coordination of each metal atom is completed by four Te atoms. The average distances are 2.799A for Nb-Te bonds and 2.560A for Ni-Te bonds.  相似文献   

2.
<正> The compound Ni2Ta2Te4 is obtained by heating the elements at 1000℃ in evacuated silica tube. Mr=989.70, orthorhombic system,space group Pma2,a = 7.914(1),b= 6.2372(5),c=7.2362(6)A,V = 357.2(1)A3, Z = 2, DC = 9.201 g/ca3,λ(MoKα)=0.7093A,μ= 537.90Cm-1.F(000)=820. Final R=0.083 and Rw=0.103 for 889 reflections.This compound is iso-structural to Ni2Nb2Te4,with two-dimensional(2D) network structure. In each cluster unit,two Ni and two Ta atons form a rhombic plane with four Ni-Ta bonds (average 2.655 A) and one Ni-Ni bond (2.512 A) without Ta-Ta interac-action. The distorted tetrahedral coordination of each metal atons is completed by four Te atoms.The average distances are 2.792A for bonds Ta-Te and 2.556 A for bonds Ni-Te.  相似文献   

3.
The title crystal is straw-yellow in colour, belonging to the triclinic system. The space group is P with the following unit cell parameters:a=11.570(2), b=13.093(1), c=14.399(2), α=102.62(1), β=102.15(1), γ=111.87 (1)°, V=1870(1), Z=2, D_(calc)=1.960g·cm~(-3).The crystal structure was solved by the heavy atom method and refined by full-matrix least-squares to a final conventional R factor of 0.055. The results show that the crystal structure consists of neutral trinuclear Mo cluster molecules, in which three independent Mo atoms form an equilateral triangle with an average side length of 2.725(3), corresponding to a Me-Me single bond. On one side of the triangle one μ_3-S atom binds the three Mo atoms together to form a monoeapped trinuclear cluster. In addition, three S_2 radicals acting as μ_2 bridges are located between each two Mo atoms. Each Mo atom is also coordinated to two terminal S atoms of an [S_2P(OEt)_2]~- radical so as to complete a distorted pentagonal bipyramid configuration.  相似文献   

4.
The title crystal belongs to the monoclinic system. The space group is P2_1/c with unit cell parameters: a=11.379(3), b=20.766(2), c=14.487(3), β=91.49(2)°, V=3519(2)~3Z=4, D_c=1.819g.cm~(-3), D_0=1.81g.cm~(-3). The crystal structure was solved by the heavy atom method and difference Fourier synthesis and refined by the full-matrix least-squares to a final R factor of 0.040 based on 3261 unique reflections with intensities I≥3σ(I). The structure consists of two sots of tetraethylammonium cations and trinuclear Me cluster anions. In the cluster anion the three Mo atoms form an isosceles triangle with Mo-Mo distances of 2.601(1), 2.608(1), 2.642(1), respectively, showing a strong bonding interaction between the metal atoms. One μ_3-O atom and one μ_3-Cl atom are situated above and below the triangle respectively, binding the three Me atoms to form a triangular bipyramidal cluster core. Each pair of Mo atoms is bridged further by a μ_2-Cl atom situated on the Mo_3 triangular plane. In addition, each  相似文献   

5.
<正> Compound Co2Nb2Te4 obtained by heating the elements Co2 Nb anc Te at 1000℃ in a evacuated silica tube, crystallizes in nonoclinic, space group P21/c with a = 8.197(2), b = 6,258(1), c = 7.816(3) A,β=118.48(2)° Z=2, X-ray structural determination shows non-molecular 2-dimensional character of its crystal structure. In the structural unit, two Co and two Nb atoms form a rhombic plane with four Co-Nb bonds (average 2.744A) and one Co-Co bond (2.514A) and there exists no Nb-Nb interaction. The distorted tetrahedral coordination of each metal atom is completed by four Te atoms. The average distances are 2.799A for Nb-Te bonds and 2.545A for Co-Te bonds.  相似文献   

6.
The title compound forms black crystals shaped like pseudo-octahedrons, which belong to the orthorhombic system The space group is Pna 2_1 with unit cell parametrs of a=17.815(1), b=16.629(2), c=12.003(1), and with Z=4, D_(obs)=1.80g·cm~(-3), and D_(calc)=1.804g·cm~(-3). The crystal structure was solved by the heavy atom method and refiened by fullmatrix least-squares to a final conventional R factor of 0.048 for 2584 unique reflections with I≥σ(Ⅰ). The investigation confirms that the crystal structure consists of tetraethylammonium cations and trinuclear Mo cluster anions. The anion is a μ_3-O monocapped trinuclear cluster with an average Mo-Mo bond length of 2.60 (2). On the side of the Mo_3 triangular plane opposite to the μ_3-O atom, each two Mo atoms are bridged by a Cl atom with the result that these seven atoms (3 Me, 1 O and 3 Cl atoms)form an apex-deficient quasicubane configuration. In addition, each Mo atom is coordinated to three additional atoms resulting in a pseudo-octahedral geome  相似文献   

7.
A summary of research on the structure of Nb/Ta layered tellurides in the past period is reported. 14 compounds, which have been structurally characterized by X-ray diffraction work, are presented according to their structural features. The first two compounds, Nb2CrTe4 and Nb2Cu1.48Te4, are characterized in that the ternary atoms are inserted in the different layers from the Nb atoms. While in the other compounds, both kinds of metal atoms are inserted in the same layer. The six compounds with formula M2M'2Te4(M = Nb/Ta; M' = Ni, Co, Fe) are characterized in that their structure can be described as construction by using cluster units "M2M'2Te10" as building blocks. in the two metal-rich compounds, TaCo2Te2 and TaNi2Te2, Ta atom has a distorted mono-capped pentagonal prism configuration. The structure of TaFeTe3, TaNTe3 and NbNi2.34Te3 can be described as building by the arrangement of double octahedral chains (DOC), in this con-nection, a selenide Ta2Ni2Se5 is also included by using the second type of  相似文献   

8.
The compound (C_5H_7S_2)_3[Mo_3 (μ_3--S)_2 (μ_2--Cl)_3 Cl_6] forms dark black octahedralcrystals with the following crystallographic parameters: a=22.885(10)A, c=25.407(7)A. Thespace group is I4_1/α, Z=16, ρ_(obs.)=2.073g/cm~3, ρ_(calc.)=2.126g/cm~3. The 1621 independentreflections with I≥3σ were collected on a CAD-4 four-circle diffractometer by means of MoK_αradiation. The structure was solved by three-dimensional Patterson synthesis and refined byleast squares technique to a final discrepancy factor of R=0.056. The results of our investiga-tion reveal that the molecule consists of a trinuclear Mo cluster anion and three planar mono-cations.surrounding the cluster anion. As the core of the anion the triad of Mo atoms, possessing anequilateral triangular configuration, is linked by two μ3--S bridging atoms and three μ2--Clatoms. Besides, two terminal Cl atoms are attached to each Mo atom to form an octahedralconfiguration. The diamagnetism and the short Mo-Mo distances (2.556 A, 2.641 A, 2.653 A)clearly indicate the existence of Mo-Mo bonds. The anion as a whole has an idealized D_(3h) localsymmetry.  相似文献   

9.
When trinuclear molybdenum cluster compound with "loose coordination site", Mo_3(μ_3-S)(μ-S)_3(μ-dtp)(dtp)_3·H_2O(A) (dtp=diethyldithiophos-phinato anion), is reacted with an excess of imidazole, the H_2O ligand and the bidentate bridging ligand μ-dtp are found to be simultaneously substituted by the imidazole to form the title compound. The title crystal belongs to the space group P(?), Z =2, with the following unit cell parameters: a=14.465(2), b=14.653(4), c=14.886(6), α=99.36(3),β=93.11(2),γ=114.29(2),V=2812(3). The crystalline compound consists of an ordered array of the cluster cation and dtp anion with acetone as packed molecule. The cation possesses a symmetry of C_3. Three Mo atoms form basically an equilateral triangle with three Mo—Mo bond lengths of 2.763 (1), 2.762(1), 2.756(1) respectively.  相似文献   

10.
The reaction of Fe_2(μ_3-Te)_2(CO)_9 with Mo_2(CO)_6(η~5-C_5H_5) affords the title compound. Its X-ray analysis shows a butterfly structure for the Mo_2Fe_2 core; the two molybdenum atoms occupy the hinge with a Mo—Mo bond distance of 2.819 and the two iron atoms are on the tops of the wings with an average Mo—Fe bond distance of 2.932(2). Each molybdenum is bonded to a Cp ring, and three CO ligands are terminally bonded to each iron atom. One tellurium atom quadruply bridges Mo_Fe_2 with Mo—Te(μ_4)=2.625(2). and Fe—Te(μ_4)=2.713(2). Two tellurium atoms triply bridge the two triangular Mo_2Fe faces with Mo—Te(μ_3)=2.678(1) and Fe—Te(μ_3)=2.513(3). The molecule has C_(2v) symmetry and a bicapped triangle bipyramidal skeleton. Crystallographic parameters are as follows: space groupImm2(orthorhombic), a=14.562(3), b=10.391(1), c=7.139(4), V=1080.2(i)~3, Z=2, ρ(cald)=1.819g·cm~(-3). The final R factor was 2.2% for 620 independent reflections(I>2σ(I)).  相似文献   

11.
<正> The nickel(Ⅱ) complex Ni2(PBu3n)2(tdt)2(tdt = SC7H6S2-) containing dithiolato and phosphino ligands has been prepared and characterized by X-ray diffraction. The complex crystallizes in triclinic system, space group P1, with a = 14. 423(4), b = 15. 053(3), c=10. 648(3)(?), α=93.,95(2), β=100. 31(3), γ = 84. 16(2)°; V =2259.6 (?)3; Z = 2, Dc= 1. 22 gem-3, Mr = 830. 57; μ = 11. 076cm-1, F (000) = 888. In the complex, the Nickel atoms are linked by two bridging sulfur atoms from the two tdt ligands with the Ni-Ni distance of 2. 679 (?) . and each nickel atom is four coordinated by one phosphorus and three sulfur atoms with a square-planar geometry, the average length of Ni -S bond is 2. 193(?) and that of Ni-P bond 2.186(?).  相似文献   

12.
The mixed ligand complex of cobalt with dibutylphosphate (HDBP) and pyridine has been synthesized. Elemental analysis yields the result that the formula of this compound is Co(DBP)_2·3Py·CHCl_3 (Py=pyridine). The thermal analsyis, visible spectra and magnetic properties of it have been studied as well. Single crystal structural analysis shows that the crystal is triclinic with space group P and the unit cell parameters are as follows:a=14.490(10), α=90.37(4)°,b=15.721(7), β=96.04(5)°,c=20.109(12), γ=105.63(4)°.The final R factor is 0.0773. Two Co atoms are connected by two bridging DBP groups to form a dinuclear molecule [Co(DBP)_2·3Py]_2 which has a C_s, symmetry. Each cell contains two dinuclear molecules and four chloroform molecules. The cobalt is coordinated in an octahedral arrangement by three oxygen atoms and three nitrogen atoms, of which one oxygen atom comes from a monodentate DBP group, two oxygen atoms from two bridging DBP groups, and the three nitrogen atoms from the three pyridi  相似文献   

13.
<正> The metal hydride Ti2Cu0.8Ni0.2H0.65, studied by X-ray diffraction and EXAFS speetroscopy, was found to have the same phase as Ti2Cu,both belonging to the tetragonal system and the I 4/mmm space group. The nearest-neighbour distance of Cu-Ti was found to be considerably shorter than, while the those of Cu-Cu and Cu-Ni almost equal to,the corresponding values in unhydrided alloy Ti2Cu0.8Ni0.2.These results suggest that the hydrogen atom occupies the tetrahedral interstitial site defined by four Ti atoms in a unit cell of Ti2Cu0.8Ni0.2H0.65.The H-Ti nearest-neighbour distance of 1. 86A is much shorter than the sum of the atomic radii of H and Ti, indicating a strong H-Ti bond . This may be an important reason for the high thermal stability of the title hydride.  相似文献   

14.
The title crystals are golden yellow rhomboic plates, belonging to the monoelinic system. The space group is P_(B_1)/n with unit cell parameters a=16.570(2), b=12.370(1), c=20.007(2), β=99.97(1)°, Z=4, D_c=1.938 g.cm~(-3). The crystal structure was solved mainly by the heavy atom method and refined by the full-matrix least-squares to a final R factor of 0.047 based on 4387 unique reflections with intensities I≥2σ(I). The results show that the crystal structure consists of neutral mono-oxo-capped trinuclear molybdenum cluster molecules with an average Mo-Mo bond length of 2.626(4) and an average Mo-O bond length of 2.036(2) respectively. Each pair of Mo atoms is further bridged by an S_2~(2-) radical, in which one S atom is essentially situated on the triangular plane formed by these three Mo atoms and the other one is situated on the side of the plane opposite to the μ_3-O atom. Besides, each Mo atom is coordinated to two S atoms belonging to an [S_2P(OEt)_2]~-radical so as to complete a nearly pen  相似文献   

15.
<正> (H2NC2H4NH2)2Ni [(C3H3N2) Co (NH3)5]2 (CIO4)6 · 5H2O,NiCo2Cl6O29N18C10H62, Mr = 1288. 00, monoclinic, C2/c, a = 31. 832(4), b = 9. 691 (1), c=15. 425(4)(?),β=90. 71(2)°, Z = 4, V = 4758. 0(?)3, Dc=1. 798g/cm3, μ (MoKa) = 15. 22cm-1, F(000)=2656. The three metal nuclei, one Ni( Ⅱ ) and two Co( Ⅲ ), bridged by two imidazolyl anions (Im = C3H3N2), form an isosceles triangle. The Ni( Ⅱ ) atom is situated on the two-fold axis and coordinated by six nitrogen atoms to form a distorted octahedron with two nitrogen atoms from two Im in cis-positions. The two Co( Ⅲ ) atoms are related by C2 symmetry and each Co( Ⅲ ) is coordinated by six nitrogen atoms to form an octahedral configuration.  相似文献   

16.
<正> (NH4)11[Na(H2O)2P4W14O58)·12H2O, Mr = 4099. 39, triclinic, space group P1, a = 14. 376(2), b = 19.861(9), c=13. 010(3)(?) , α=104. 68(2), β=91. 37(1), γ= 104. 05(2)°, V = 3471. 1 (?)3, Z = 2, Dc=3. 922g/cm3, μ (MoKα) = 238. 274cm-1, F(000) = 3664, R = 0.0510, Rw = 0. 0665 for 9260 observed reflections with I> 3σ(I). The polyanion [Na(H2O)2P4W14O58]11- consists of two PW7O29 subunits anisostructurally, two linkage phosphorous atoms and one sodium ion with two water ligands as well. The geometries of tungsten atoms within these two subunits are almost the same as those in K12P4W14O58· 21H2O[2]. The four phosphorous atoms are in PO4 coordinations. The sodium ion locates nearly at the center of the polyanion, and is coordinated by two water molecules, five oxygen atoms of the anion and one phosphorous atom with Na-P = 3. 053(3) (?). Due to the presence of the sodium atom, the interactions between oxygen and tungsten atoms in the polyanion are somewhat weakened.  相似文献   

17.
李静  王玉红  宋瑞峰 《结构化学》2014,33(10):1488-1494
A novel two-dimensional lead(II) coordination polymer 1, [C11H7Cl2NO3Pb]n, has been prepared by solvothermal reaction of new bridging ligand(5-chloro-quinolin-8-yloxy)acetic acid(HL) with PbCl2, and its structure was characterized by IR, elemental analysis, TG-DTA and single-crystal X-ray diffraction analysis. The crystal is of monoclinic system, space group P21/c with a = 16.7603(7), b = 8.6907(4), c = 8.4745(3), β = 101.1110(11)°, C11H7Cl2NO3 Pb, Mr = 479.27, V = 1211.25(9)3, Z = 4, Dc = 2.628 g/cm3, F(000) = 880, μ = 14.367 mm-1, R = 0.0173 and wR = 0.0508. The asymmetric unit contains one lead(II) cation, one(5-chloro-quinolin-8-yloxy)acetate(L) ligand and a chloride ion. The PbII center is hepta-coordinated in a distorted pentagonal bipyramidal geometry. The coordination sphere of the Pb atom is completed by two oxygen atoms and one nitrogen atom of the same L ligand, two bridging chloride ions and two bridging oxygen atoms of two adjacent L ligands. Two PbII centers are linked by the two L ligands to form a C2-symmetric dimer unit with a planar [Pb2O2] ring. Each dimer unit acts as a secondary building unit(SBU) and links adjacent four dimer units by the chloride atoms and oxygen atoms of carboxylate groups of L, forming a two-dimensional array. Such two-dimensional layers are packed through intermolecular C–H···Cl hydrogen bonds into a three-dimensional supramolecular structure. When the dimer unit is viewed as a 4-connected node, 1 is simplified as a 4-nodal 2-D network with square lattices of the diagonal lengths to be 6.079(1). The fluorescence emission peak of complex 1 appears near 407 nm.  相似文献   

18.
Two novel complexes, [Cd2(BMQU)2Cl4] (1) and [Ni(BMQU)2HPO4]·1.5H2O (2) (BMQU = 2-(2-benzimidazolyl)quinoline), were synthesized by the hydrothermal method and characterized by elemental analysis, IR, and TG-DTG. The crystal structures were determined by single-crystal X-ray diffraction. Both 1 and 2 crystallize in the triclinic system, space group P . The data for 1: a = 0.8342(7), b = 0.9226(9), c = 1.0646(8) nm, α = 90.819(2), β = 97.466(2), γ = 98.280(2)°. The Cd(Ⅱ) is coordinated with three chlorine atoms and two nitrogen atoms of a BMQU molecule, generating a distorted square-pyramidal geometry. The dinuclear Cd(Ⅱ) complex is formed by two chlorine bridge bonds, and the one-dimensional chain structure is constructed with the hydrogen bond N-H…Cl and π-π stacking interaction. The data for 2: a = 1.2251(1), b = 1.2451(1), c = 1.2868(1) nm, α = 107.510(2), β = 98.630(1), γ = 109.921(2)°. The Ni(Ⅱ) is coordinated with four nitrogen atoms of two BMQU molecules and two oxygen atoms of a HPO42-, forming a distorted-octahedral geometry. The two-dimensional layer structure is formed by the hydrogen bonds and π-π stacking interaction between neighboring molecules. Complex 1 shows a strong blue fluorescence emission (λmax= 456 nm) at solid state.  相似文献   

19.
<正> Mr = 1445.67, triclinic. The space group is P1 with the unit cell parameters: a = 10.342(3), b = 11.994(3), c = 21.352(4) A; (?)= 76.27(2), β - 88.55(2)°, r = 73.26(2)°; V = 246lA3, Z = 2, DC = 1.959 g.cm-3. The final R factor is 0.068 based on 4053 reflectioons with I≥3(?)(Ⅰ). The title compound may be regarded as the result of that a molecule of trinuclear Mo cluster {Mo3S4[S2P(OEt)2]4·(C3H3ON)}[1] connects with a molecule of SbCl3 by three bridging S atoms. The skeleton {Mo3SbS4} is a distorted cube. The distances of Mo-Mo bonds are 2.728(2), 2,743(2) and 2.751(2) A, respectively, and the distances between Sb and Mo atoms are 3.814(2), 3.815(2) and 3.847(2) A, respectively.  相似文献   

20.
A Schiff base zinc(Ⅱ) complex [Zn(C12H16BrClN2O)2(NCS)2] was prepared and characterized by elemental analysis, IR and single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P with a = 8.414(1), b = 9.124(1), c = 22.212(3) (A), α = 79.177(2), β = 86.296(2), γ = 89.899(2)o, V = 1671.3(4) (A)3, Z = 2, Dc = 1.631 g/cm3, Mr = 820.79, λ(MoKα) = 0.71073 (A), μ = 3.444 mm-1, F(000) = 824, R = 0.0646 and wR = 0.1179. A total of 7371 unique reflections were collected, of which 3904 with I>2σ(I) were observed. The complex crystallizes with two half-molecules per asymmetric unit and each mononuclear molecule is centrosymmetric. The Zn atom lying at the inversion centre is six-coordinated in a slightly distorted octahedral geometry by two phenolate O atoms and two imine N atoms from two Schiff base ligands, as well as two N atoms from two thiocyanate anions. In the crystal structure, the combination of π-π stacking interactions and intermolecular hydrogen bonds (N-H…Br, N-H…O, N-H…N, C-H…O, C-H…S and C-H…Cl) leads to a three-dimensional network.  相似文献   

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