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81.
82.
<正>The reaction of phenyl 2-pyridyl ketoxime(PhPyCNOH)with Cu(NO_3)_2·3H_2O has led to a triangular complex Cu_3(OH)(PhPyCNO)_3(NO_3)·NO_3·H_2O 1 containing the[Cu_3(μ_2-OH)]~(5+) core and possessing the very rare inverse 9-metallacrown-3 motif created by the bridging oximate groups.Crystallographic data for 1:C_(36_H_(30)N_8O_(11)Cu_3,M_r=941.30,monoclinic,space group C2/c,a =18.815(9),b=33.888(15),c=14.307(7)(?),β=118.945(6)°,V=7983(6)(?)~3,Z=8,D_c=1.566 g/cm~3,n=1.652 mm~(-1),F(000)= 3816,R= 0.0644 and wR= 0.1393 for 3468 observed reflections(I2σ(I)).Preliminary variable-temperature magnetic susceptibility studies reveal an antiferroma-gnetically -coupled system showing antisymmetric exchange.  相似文献   
83.
A novel two-dimensional cadmium(Ⅱ) complex {[Cd(bpds)(bpp)2]·2H2O}n (1) with 4,4′-biphenyldisulfonic acid (H2bpds) and 1,3-bis(4-pyridyl)propane (bpp) has been synthesized by means of hydrothermal method and characterized by elemental analysis, IR spectrum, thermal analysis and single-crystal X-ray diffraction. The crystal is of triclinic, space group P1 with a=0.900 96(12) nm, b=1.098 84(14) nm, c=1.125 71(15) nm, α=115.907(2)°, β= 92.307 (2)°, γ=105.383 (2)°, V=0.950 8(2) nm3, Dc=1.497 g·cm-3, Z=1, F(000)=440, Goof=1.046, R1=0.028 2, wR2= 0.074 9. Complex 1 shows a novel two-dimensional (2D) lamellar structure and further extended into a 3D supramolecular structure through O-H…O and C-H…O hydrogen bonding interactions. Luminescent studies show that complex 1 exhibits intense blue fluorescent emission. CCDC: 769593.  相似文献   
84.
A novel pyridyl-dicarboxylate Schiff-base ligand (5-((pyridin-3-ylmethyl)amino)isophthalic acid,H2L) and its Zinc(Ⅱ) complex,namely,ZnL (1),were synthesized. The ligand was characterized by NMR analysis. The X-ray crystallographic analysis on complex 1 shows that 1 crystallizes in homoclinic,space group P21/c with a= 0.753 83(10) nm,b=1.040 52(14) nm,c=1.734 67(19) nm,β=112.123(5)°,V=1.260 5(3) nm3,Z=4,Dc=1.769 g· cm-3,F(000)=680,μ=1.966 mm-1,the final R=0.030 8,wR=0.085 6. In complex 1,the coordination environment of Zn(Ⅱ) is distorted tetragonal-pyramid with N1O4 set. The 2D 4,4-topological sheets in 1 packed along a axis to form its 3D framework,which was stabilized by the π…π interactions between the adjacent aromatic rings on the neighbouring sheets. The photoluminescent property of 1 was also investigated.  相似文献   
85.
<正>Great interest has been focused on the rapidly expanding field of the construction of novel functional metal-organic frameworks(MOFs)owing to their variety of intriguing architectures and topologies and their potential applications in magnetism  相似文献   
86.
合成了柔性配体3-吡啶甲酸-1,2-乙二酯(3-pyridinecarboxylic acid 1,2-ethanediyl ester,pcaede),并将其分别与Co盐和Hg盐进行组装,得到4个新配合物[Co(pcaede)2Cl2.2CH3CN.H2O]n(1),[Co(pcae-de)2Cl2.H2O]n(2),[Hg(pcaede)I2]n(3)和[Hg(pcaede)Br2]n(4),对其进行了元素分析、红外光谱及X射线单晶结构分析.配合物1和2为含有孔道的一维链状结构,配合物3是1D内消旋螺旋链,配合物4则是锯齿形1D链状结构.研究结果显示,孔道中填充的溶剂分子和平衡阴离子对配合物的组装有显著的影响.此外对4个配合物中配体的构象进行了理论计算.  相似文献   
87.
刘光祥  严娟  朱坤  陈宏  任小明 《结构化学》2009,28(2):181-186
A novel compound, (IBzQI)(TCNQ)2 2 (IBzQ1=1-(4-iodobenzyl)quinolinium and TCNQ = 7,7,8,8-tetracyanoquinodimethane) has been fabricated and X-ray single-crystal structurally analyzed. This compound crystallizes in the triclinic system, space group P1 with a = 8.3540(17), b = 13.284(3), c = 16.185(3) А, α= 82.12(3), β= 75.19(3), γ= 72.34°, V = 1651.2(6) А^3, Z= 2, C_40H_21IN_9, Mr = 754.56, Dc = 1.518 g/cm^3,μ= 1.015 mm^-1, S = 1.010, F(000) = 754, R = 0.0387 and wR = 0.0948. The structure analysis shows that the anions are stacked into column with tetrads, and there are two types of TCNQ entries (TCNQ-1 and TCNQ^0) in agreement with the IR spectra analysis of the compound. The temperature dependence of the magnetic susceptibility (2-300 K) for 2 exhibits spin gap of singlet-triplet feature, and the best fit gave △/kB = 1523.4 K. In order to understand both magnetic behavior and local charge distribution of [(TCNQ)2]-unit, the molecular orbital calculations and analysis based on extended Hückel method were performed, and the results support the analyses of both crystal structure and IR spectra.  相似文献   
88.
A novel cobalt(II) coordination polymer,[Co(BTEC)1/2]n 1,has been synthesized with Co(NO3)2·6H2O and 1,2,4,5-benzenetetracarboxylic acid (H4BTEC) by the hydrothermal method,and characterized by elemental analysis,IR and single-crystal X-ray diffraction. Crystallographic data for 1: C5HO4Co,Mr = 183.99,monoclinic,space group C2/c,a = 16.619(6),b = 7.416(3),c = 8.040(3)A,β = 90.612(4)°,V = 990.8(6) A^3,Z = 8,Dc = 2.467 g/cm^3,μ = 3.390 mm^-1,F(000) = 720,R = 0.0307 and wR = 0.0847 for 912 observed reflections (I 〉 2σ(I)). X-ray crystal structural analysis revealed that each Co(II) adopts a tetrahedral coordination mode to link four separate BTEC ligands via uniform monodentate carboxylate groups and each BTEC ligand possesses an 8-connected geometry to connect eight Co(II) ions. Complex 1 exhibits a rare (4,8)-connected net with (45.6)2(410.614.84) topology.  相似文献   
89.
运用密度泛函理论,在B3LYP/6-31G(d)水平上对菲并咪唑(PI)及其8种2-取代芳基衍生物的结构进行了全优化,探讨了取代基对分子结构、电离势(I_P)、电子亲和势(E_A)、电荷转移、前线分子轨道能量和电子吸收光谱等方面的影响.采用含时的度泛函理论(TD-DFT)计算了各分子的气相及液相的电子吸收光谱,计算结果与实验值十分接近.并用GaussSum2.1程序模拟吸收光谱和态密度(DOS)图,结果表明,芳基4′-位上取代基对菲并咪唑(PI)和苯环的骨架结构没有很大的扰动,但它们重新调整了菲并咪唑环和苯环中原子电荷分布,前线分子轨道(LUMO)-HOMO)能隙降低,导致8种取代的化合物的吸收波长均发生了红移.  相似文献   
90.
A novel cobalt complex,[Co2(bptc)(bix)1.5](1,H4bptc=3,3',4,4'-biphenyltetra-carboxylic acid,bix = 1,4-bis(imidazol-1-ylmethyl)benzene),has been hydrothermally prepared and characterized by IR spectroscopy,elemental analysis and single-crystal X-ray diffraction.The crystal is of triclinic system,space group P1 with a=10.770(7),b=12.245(8),c=13.514(9),α=102.829(8),β=107.734(8),γ=98.833(9)°,C37H27N6O8Co2,Mr=801.51,V=1607.5(18)3,Dc=1.656g/cm3,F(000)=818,μ=1.100mm-1,Z=2,the final R = 0.0694 and wR = 0.1543 for...  相似文献   
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