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81.
分别以(8R,10R)-(-)-[4,5]-pineno-2,2′-bipyridine或(8S,10S)-(+)-[4,5]-pineno-2,2′-bipyridine(LRR和LSS)为手性配体合成双核铜络合物[Cu2(μ-ox)(LRR)2(H2O)2(ClO4)2](1)、[Cu2(μ-ox)(LRR)2(CH3COCH3)2(ClO4)2](1a)、[Cu2(μ-ox)(LSS)2(H2O)2(ClO4)2](2)和[Cu2(μ-ox)-(LRR)(LSS)(CH3COCH3)2(ClO4)2](3)(ox2-=草酸根),并探讨了其反应机理.由元素分析、电导率、紫外可见谱(UV-vis)、圆二色(CD)谱和晶体结构分析推测:该系列络合物具有草酸根桥联的双核结构,两个铜(II)离子与草酸根几乎成共平面;1a和3的晶体结构分析表明,每个Cu(II)的配位构型为拉长畸变八面体,双核分子中轴向的两个溶剂分子和两个高氯酸根互为反式配位.对映体络合物1和2的溶液CD光谱大致呈镜像对称,在可见区的极弱CD吸收峰可能源于LRR和LSS蒎烯基上的手性中心对Cu(II)d-d生色团的手性微扰产生的邻位效应.采用最小二乘法和Bleaney-Bowers方程对络合物1的变温磁化率测试数据进行拟合,求得交换积分J=-338.41(4)cm-1,表明铜(II)离子间有较强的反铁磁自旋交换作用.  相似文献   
82.
The preparation of divalent chromium N-heterocyclic carbene(NHC,1,3-diisopropyl4,5-dimethylimidazole-2-ylidene) compounds is reported.The reaction of 1:1 molar ratio of NHC with CrCl2 led to an isolation of [(NHC)CrCl(μ-Cl)(THF)]2(1),while that of 2:1 ratio resulted in the formation of(NHC)2CrCl2(2).1 can be considered as an intermediate in the formation of 2 and further converted into 2 by the addition of another equiv.of NHC.The reaction of 2 with CpNa afforded an ion pair compound [(NHC)2CrCp]+[Cp]-(3),indicating a strong coordination ability of NHC supplanting one of the ionic Cr-Cp bonding.In combination of methylalumoxane(MAO) as cocatalyst 1 and 2 both are active for catalyzing ethylene polymerization.  相似文献   
83.
Two novel mono-nuclear zinc(Ⅱ) complexes with oligoaniline-functionalized terpyridine ligands have been synthesized and verified by 1H-NMR,13C-NMR,Elemental Analysis (EA) and X-ray Diffraction (XRD). The UV-vis spectra show the ligand-centered (LC) π-π* transitions and intra-ligand charge transfer (1ILCT) transitions,and the 1ILCT band red-shifts with the increasing number of aromatic amine groups in the ligands. Complex [Zn(L1)2](PF6)2 with an aromatic amine group in ligand shows a strong emission peak at 523 nm in the MeCN solution at 293 K and a blue-shifted band at 517 nm in the alcoholic glass at 77 K. However,for complex [Zn(L2)2](PF6)2 containing aniline dimer modified ligand,no apparent emission can be observed in the MeCN solution at room temperature due to a PET non-radiative decay pathway. Both of them show multiplicate redox processes based on oligoaniline and terpyridine units. The shifts of redox potentials also reflect the D-A interactions between the oligoaniline units and [Zn(TPY)2]2+ core.  相似文献   
84.
Two cadmium arsonate coordination polymers, Cd(HL1)2 (1, H2L1 = 4-aminophenylarsonatic acid) and Cd(H2L2)2·2H2O (2, H3L2 = 2-(4-arsonphenylamino)acetic acid), have been synthesized and characterized by IR and single-crystal X-ray diffraction. Crystal data for 1: triclinic, space group P1 with a = 5.7559(12), b = 7.0903(14), c = 8.9925(18), α = 89.04(3), β = 80.79(3), γ = 85.09(3)o, Dc = 2.496 g·cm-3, μ = 6.095 mm-1, F(000) = 260, Z = 1, the final R = 0.0574 and wR = 0.1376 for 1489 observed reflections with I > 2σ(I). And those for 2: monoclinic, space group P21/c with a = 4.7595(10), b = 9.925(2), c = 22.609(5), β = 91.81(3)°, Dc = 2.167 g·cm-3, μ = 4.168 mm-1, F(000) = 684, Z = 2, the final R = 0.0335 and wR = 0.0815 for 2340 observed reflections with I > 2σ(I). The structure of 1 shows a two-dimensional layer consisting of inorganic chains of {CdN2(AsO3)2} along the a axis linking with the phenyl groups. These layers are further linked through strong interlayer hydrogen bonding interaction to form a three-dimensional hydrogen bond supramolecular architecture. Compound 2 has inorganic chains of {CdO2(AsO3)2} similar to 1, which connect with four adjacent inorganic chains forming a three-dimensional framework.  相似文献   
85.
A planar transition metal complex Cu(L)2 (L = (E)-benzyl-2-(4-nitrobenzylidene)-hydrazinecarbodithioate) has been prepared and determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system,space group P21/c with a = 6.7101(11),b = 16.952(3),c = 13.962(3) ,β = 92.458(4)°,V = 1586.7(5) 3,Z = 4,Mr = 724.33,Dc = 1.516 g·m-3,μ = 0.998 mm-1,F(000) = 742,S = 1.021,R = 0.0634 and wR = 0.1077 for 813 observed reflections with Ⅰ 2σ(Ⅰ) and 205 parameters. In the molecular structure of the title complex,the copper atom exhibits a slightly distorted square-planar geometry in which the basal plane is defined by two N and two S atoms from two bidentate ligands. The complex was evaluated for its antitumor activity against two kinds of cell lines (MKN45 and HepG2) by MTT method. The preliminary bioassay indicates that the complex exhibits weak antitumor activity.  相似文献   
86.
The title compound,[Zn2(H2C4BIm)(ox)2]·2H2O(1,H2C4BIm = 2,2'-(1,4-bu-tanediyl)bis(1H-benzimidazole),has been synthesized by the hydrothermal reaction of Zn(NO3)2·6H2O with H2C4BIm and Na2C2O4 in water solution.It crystallizes in the triclinic system,space group P1 with a = 9.445(9),b = 9.598(9),c = 14.962(14) ,α = 72.160(10),β = 79.905(12),γ = 83.680(11)°,Mr = 633.18,V = 1269(2) 3,Z = 2,Dc = 1.657 g/cm3,F(000) = 644,μ = 1.953 mm-1,the final R = 0.0671 and wR = 0.1689.X-ray crystal structure analysis revealed that 1 is a 3D network with(203)2(20)3 topology in which the ZnII atom can be considered as a 3-connected node and both ox2-and H2C4BIm serve as the linear linkers.  相似文献   
87.
用牛磺酸与2-吡啶甲醛反应合成了一种牛磺酸Schiff碱,并制备了它与Cu(Ⅱ)的配合物[CuL(H2O)].NO3,其中HL=C8H10N2O3S,利用元素分析,红外光谱,紫外光谱,差热-热重分析及摩尔电导的测定等方法对Schiff碱及金属配合物进行了表征。  相似文献   
88.
在曲拉通X-100(TritonX-100)和乳化剂(OP)存在下,基于Cu2+-铬天青S(CAS)的显色反应,建立了分光光度法测定微量铜的新方法.通过Cu2+与CAS-Triton X-100-OP形成灵敏度较高的多元配合物,来测量铜含量.络合物的最大吸收波长为618nm,表观摩尔吸光系数为ε=6.62×105L·m...  相似文献   
89.
本文总结了近年来Ⅲ族氮化物半导体异质结构二维电子气的研究进展。从Ⅲ族氮化物材料晶格结构和特有的极化性质出发,重点讨论了AlGaN/GaN异质结构中二维电子气的性质,总结分析了异质结构中Al组分、势垒层厚度、应变弛豫度、掺杂等对二维电子气浓度和迁移率的影响,同时还涉及AlGaN/GaN/AlGaN,AlGaN/AlN/GaN和AlGaN/InGaN/GaN等异质结构二维电子气性质。  相似文献   
90.
张晓荷  王冬杰  夏海平 《物理学报》2011,60(2):24210-024210
通过卟啉配合物Meso-四(4-羧基苯基)卟啉铜(简称Cu(Ⅱ)-TCPP)中的羧基与γ-氨基丙基三乙氧基硅烷(NH2(CH2)3Si(OC2H5)3,KH550)中的氨基的相互化学作用,成功地把卟啉配合物接枝到KH550中,随着KH550中乙氧基的水解与聚合反应的进行,卟啉铜连接到固体介质中,从而大幅度提高了卟啉在无机固体介质中的掺杂浓度. 将反应产物与γ-(2,3-环氧丙氧基)丙基三甲氧基硅烷(CH2CHCH2O(CH2)3Si(OCH3)3,KH560) 相杂化,形成物化性能良好、连接卟啉的有机-无机复合材料. 用红外光谱表征了Cu(Ⅱ)-TCPP与KH550的化学反应产物,用紫外—可见吸收光谱研究Cu(Ⅱ)-TCPP的分子状态. 应用Z扫描技术研究不同Cu(Ⅱ)-TCPP掺杂浓度的复合材料的非线性光学性质,其三介非线性折射率n2达-1.1161×10-16 m2/W. 关键词: 非线性折射率 有机-无机复合材料 接枝 Meso-四(4-羧基苯基)卟啉铜  相似文献   
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