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881.
A novel viologen(4,4'bipyridinium)-based complex (CH3-4,4'-H2bipy)(HgCl4) (1),in which the CH3-4,4'-H2bipy (MQ2+) was generated in situ,has been synthesized via hydrothermal reaction and structurally characterized. Complex 1 crystallizes in the space group P21/c of monoclinic system with four formula units in a cell:a = 8.1848(6),b = 21.809(2),c = 9.0285(6) ,β = 107.377(1)°,V = 1538.0(2) 3,C11H11Cl4HgN2,Mr = 513.61,Dc = 2.218 g/cm3,S = 1.009,μ(MoKα) = 10.685 mm-1,F(000) = 956,R = 0.0360 and wR = 0.0812. The crystal structure analysis reveals that the title complex features an isolated structure based on a CH3-4,4'-H2bipy moiety and a mercury atom terminally bound by four chlorine atoms. Photoluminescence investigation reveals a strong emission in blue region,which may originate from π→π* charge-transfer interaction of the CH3-4,4'-H2bipy moiety.  相似文献   
882.
A new dinuclear complex [Zn(dpa)(bipy)(H2O)]2 (dpa = 2,2'-diphenic acid, bipy = 2,2'-bipyridine) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, fluorescence spectrum and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group P21/c with a = 10.960(2), b = 9.4841(18), c = 20.599(4), β = 104.452(3)o, V = 2073.4(7)3, C48H36N4O10Zn2, Mr = 959.55, Dc = 1.537 g/cm3, μ(MoKα) = 1.225 mm-1, F(000) = 984, Z = 2, the final R = 0.0364 and wR = 0.0843 for 2788 observed reflections (I > 2σ(I)). In the crystal structure, the zinc atom is five-coordinated with two carboxylate oxygen atoms from different dpas, one coordinated water molecule and two nitrogen atoms from bipy ligands, showing a slightly distorted triangular bipyramidal geometry. Furthermore, it exhibits a zero-dimensional network structure with a sixteen-membered ring and shows yellow photoluminescent property at room temperature.  相似文献   
883.
A new pseudo Keggin-type bicapped compound(Et3N)0.5(en)2[SiMo12O40(VO)2]·4H2O(Et3N=triethylamine,en=ethylenediamine) has been hydrothermally synthesized and characterized by IR,elemental analysis,TG and X-ray crystallography.The title compound crystallizes in monoclinic,space group P21/n with a=17.576(2),b=13.535(1),c=21.587(2),β=103.790(10)°,V=4987.3(8)3,Z=4,Dc=2.925 Mg/m3,Mr=2196.12,F(000)=4148,μ=3.400 mm-1,R=0.0379 and wR=0.1219.The most remarkable structural feature of the compound is that the clusters represent bicapped pseudo-Keggin structure and are linked one by one through V-O-V bonds forming an infinite 1D chain.Furthermore,such chains are interconnected in a cross-like arrangement through multiform hydrogen bonds to yield a 3D supramolecular network.  相似文献   
884.
A dinuclear cadmium complex [Cd2(phen)2(C14H11O3)4(CH3CH2OH)]·(CH3OH)·(H2O) has been synthesized with benzilic acid and 1,10-phenanthroline by hydrothermal method.The crystal structure was determined by X-ray diffraction with crystal parameters as follows:triclinic system with space group P1,a = 1.21298(10),b = 1.32586(11),c = 2.4815(2) nm,α = 76.2630(10),β = 81.4500(10),γ = 69.1700(10)o,V = 3.6143(5) nm3,Dc = 1.438 g/cm3,Z = 1,F(000) = 1600,the final GOOF = 0.937,R = 0.0521 and wR = 0.1328.In the title complex,the dinuclear structure is defined by carboxyl oxygen atoms adopting a monodentate bridged coordination mode.The coordination environment of Cd(Ⅱ) ion is CdO4N2,giving a distorted octahedral coordination geometry.TG analysis shows that the title complex is stable under 140 ℃.  相似文献   
885.
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   
886.
Two molybdophosphate compounds,[Ni(bim)3]2[H2P2Mo5O23]·2H2O 1 and [Zn(bpy)2]2[Zn(bpy)(H2O)]2Zn[Mo6O12(OH)3(HPO4)4]2·9H2O 2 (bim = 2,2'-biimidazole,bpy = 2,2'-dipyridyl),have been synthesized under hydrothermal conditions and structurally characterized by elemental analysis,TG,and IR. The single-crystal X-ray analysis exhibits that 1 consists of one [H2P2Mo5O23]4-,two [Ni(bim)3]2+ cations and two lattice water molecules,while 2 is constructed from one sandwich-type [ZnP4Mo6] anion modified by four Zn-bpy complexes and nine lattice water molecules. The electrochemical behaviors of compounds 1 and 2 have been studied in detail based on solid bulk modified carbon paste electrodes of compound (CPEs).  相似文献   
887.
<正>1982年Wilson等首次以有机胺作为模板剂,通过水热法合成了由Al-O和P-O共享氧桥交替组合而成的磷酸铝分子筛(AlPO4)[1],由于其骨架呈中性,表面酸性和催化能力较弱,使其应用受到影响。通过在磷酸铝分子筛骨架上引入金属或非金属杂原子,同晶置换部分骨架中的磷和铝,使骨架电荷  相似文献   
888.
<正>近年来,设计合成新型的金属-有机配位聚合物受到了人们的青睐,由于它们在结构上的多样性导致了它们在磁性、催化、电子导体等领域具有广泛的潜在应用[1-4]。因此,在设计合成这些配合物的过程中,金属和配体的选择对其结构性质都会产生很大的影响。其中,在金属选择中,我们发现具有高配位数的稀土元素有助于合成结构新颖的配位聚  相似文献   
889.
由Pb-O螺旋链构筑具有罕见ecl拓扑结构的铅(Ⅱ)配位聚合物   总被引:2,自引:0,他引:2  
Under hydrothermal condition, a novel coordination polymer [Pb(C4H4O6)]n has been successfully synthesized by reaction flexible racemic ligand D,L-tartaric acid (C4H4O6) and Pb(Ⅱ)(NO3)2. Its structure is determined by single-crystal X-ray diffraction analysis and further characterized by X-ray powder diffraction, IR, CHN and TG analyses. It crystallizes in tetragonal, space group I41/acd with a=1.569 0(2) nm, c=1.009 5(2) nm, V=2.485 0(7) nm3, Z=16. Its structure contains left- and right-handed helical chains. Such helical chains with opposite chirality are alternatively arranged and further connected to form a three-dimensional framework. Topology analysis shows that it presents rare ecl topological structure. CCDC: 771026.  相似文献   
890.
<正>过渡金属配位聚合物因其丰富的网络拓扑结构及其在吸附、催化、分子识别、光、电、磁等方面的潜在应用而成为无机化学和材料化学研究领域中  相似文献   
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