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A Keggin-type tungstosilicate compound [Co^Ⅱ(2,2′-bipy)2(H2O)]2[SiW^Ⅵ12O40]·2H2O 1 (bipy = bipyridine) was prepared by a hydrothermal method for the first time. Single-crystal X-ray diffraction revealed that 1 (C40H40Co2N8O44SiW12) crystallizes in the triclinic system, space group P1 with a = 10.4979(6), b = 13.3946(7), c = 13.5756(8)A, α= 70.0769(18), β = 68.910(3), γ = 74.186(4)°, V = 1649.84(16)A^3, Mr = 3688.95, Z = 1, Dc = 3.713 mg·m^-3, μ = 21.432 mm^-1, F(000) = 1644, S = 1.058, the final R = 0.0511 and wR =0.1023 for 6523 observed reflections (I 〉 2σ(I)). Compound 1 consists of two coordinated cation fragments [Co^Ⅱ(2,2′-bipy)2(H2O)]^2+, one normal Keggin polyanion unit [SiW^Ⅵ12O40]^4- and two lattice water molecules. To be noted, each polyanion unit is linked to two cation fragments by its two surface terminal oxygen atoms and two cobalt atoms of two cation fragments forming an organic-inorganic hybrid unit in 1. Furthermore, the compound shows strong photoluminescence property in the solid state at room temperature.  相似文献   
2.
The title compound, 2,6-bis(benzimidazo(1,2-c)quinazolin-6-yl)pyridine tetrahydrate, was synthesized by simple condensation of 2-(2-sminophenyl) benzimidazole with pyfidine- 2,6-dicarboxylic acid and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group C2/c with a = 22.226(8), b = 16.730(7), c = 16.820(5)A, β = 115.796(13)°, V = 5631(4)A^3, C33H27NTO4, Mr = 585.62, Z = 8, Dc = 1.381 g/cm^3, λ(MoKα) = 0.71073 A, F(000) = 2448 and μ = 0.09 mm^-1. The structure was refined to the final R = 0.0730 and wR = 0.1573 for 6346 independent reflections (Rint = 0.0801) and 3384 observed reflections (I 〉 2σ(I)). In the crystal, the molecules are linked through intermolecular O-H…O and O-H…N hydrogen bonds. Intermolecular π-π interactions (with distances of about 3.45 A) are pronounced in the crystal structure.  相似文献   
3.
A new pseudo three-dimensional framework structure of the title compound {[CuⅡ(1,10-phen)]2[PMoⅥ11MoⅤO40]}[CuⅠ(C8N4H6)(C9H6NO)(H2O)](1) has been prepared by the hydrothermal method for the first time and characterized by elemental analyses,X-ray single-crystal diffraction and IR spectra.1 consists of two building blocks,one {[CuⅡ(1,10-phen)]2[PMoⅥ11MoⅤO40]} and one [CuⅠ(C8N4H6)(C9H6NO)(H2O)] coordinated group.Singlecrystal X-ray diffraction revealed that 1 crystallizes in the monoclinic system,space group P2/c with a=13.498(4),b=12.890(3),c=21.465(8),β=97.314o,V=3704(2)3,Mr=2693.61,Z=2,Dc=2.415 Mg/m3,μ=2.915 mm-1,F(000)=2562,S=1.009,the final R=0.0583 and wR=0.1406 for 5129 observed reflections with I2σ(I).Furthermore,compound 1 shows strong fluorescent properties in the solid state at room temperature.The electrochemical behavior of 1 has also been studied by cyclic voltammograms.  相似文献   
4.
在水热条件下合成了一个由过渡金属有机配位亚单元通过超分子相互作用和静电作用修饰的多金属氧酸盐[V1(1,10-phen)3]2[SiWv112O40]·C4H10N2,通过单晶X-射线衍射和红外光谱对其结构进行表征,并研究了其荧光性质和电化学行为.结果表明,标题化合物属三斜晶系,Pi-空间群,晶胞参数a=1.31940...  相似文献   
5.
A new tripodal P,N ligand (C63H48N3O3P3) was prepared and characterized by elemental analysis, IR and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 13.013(3), b = 28.406(6), c = 14.911(3) A^°, β= 111.04(3)°, V= 5144.6(18) A^°^3 Z = 4, Dc = 1.276 g/cm^3, Mr = 987.95, λ(MoKa) = 0.71073 A^°,μ = 0.17 mm^-1, F(000) = 2064, R = 0.0786 and wR = 0.1545. A total of 43260 unique reflections were collected, of which 5112 with I 〉 2σ(I) were observed. The title compound has a central benzene ring, which is linked by -NH-CO- bonds to three 2-aminophenyltriphenylphosphium moieties, of which two with P(1) and P(2) centers are pointing to the same face of the central aryl ring, while the third one directs oppositely, forming a pseudo-propeller. In the crystal structure, there exist face-to-face π-π stacking interactions which increase the stability of the crystal structure.  相似文献   
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针对水平和竖向地震作用下高层建筑结构的混合振动控制问题,研究调谐质量阻尼器(tuned mass damper, TMD)体系、隔震结构体系、隔震与TMD混合控制体系3种策略对水平与竖向地震共同作用下结构振动响应的减振效果。选取典型的20层钢结构Benchmark结构模型,利用ANSYS软件建立带有TMD和隔震层结构的有限元模型,比较了结构在水平地震单独作用下与水平和竖向地震共同作用下的振动响应。结果表明,水平方向上的振动响应无明显变化;竖直方向上,有控状态下的减振指标相对于无控状态出现了增大现象,尤其是层间隔震结构增大较为明显。研究成果可为高烈度区高层隔震结构设计提供参考。  相似文献   
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