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1.
Hydrothermal reactions of two imidazole derivatives(1,3,5-tib = 1,3,5-tris(1Himidazol-1-yl)benzene, 1,4-bimb = 1,4-bis(1H-imidazol-1-ylmethyl)benzene) and the ZnⅡ cations in the presence of oxalic acid(H2ox) afford two coordination polymers, namely, {[Zn(ox)(1,3,5-tib)]·2(H2O)}n(1) and [Zn1.5(ox)1.5(1,4-bimb)1.5]n(2). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction(PXRD) analyses. Both complexes 1 and 2 are based on the 1D zigzag [Zn(ox)]n chains, and their final structures are controlled by the two different imidazole linkers, which expanded the structure along different directions, finally giving a 3D dia net for 1 and a 2D sql layer for 2. Moreover, the luminescent properties of 1 and 2 have been investigated.  相似文献   
2.
Hydrothermal reactions of three aromatic polycarboxylic acids and the transitional metal cations in the presence of phen and 1,4-bib afford three new coordination polymers: [Cd2(bpp)1.5(Hbpp)(phen)2]n(1), [Mn3(Htptc)2(phen)2(H2O)2]n(2), and {[Cu(btc)0.5(1,4- bib)]·2H2O}n(3)(H2bpp = 2,6-bis(4'-carboxyphenyl)-4-phenylpyridine, H4tptc = terphenyl-2,5,2',5'-tetracarboxylic acid, H4btc = biphenyl-2,2',4,4'-tetracarboxylic acid, phen = 1,10-phenanthroline, and 1,4-bib = 1,4-bis(1H-imidazol-1-yl)benzene). Their structures have been determined by singlecrystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction(PXRD) analyses. In compound 1, the CdII cations are linked by bpp2- to form one ladder structure, based on which a 3D network is constructed with the help of non-covalent interactions. The topology of 2 is a 3D(3,4,5)-connected framework with the Point Schl?fli symbol of(42.6)32(4.62.8)(45.64.8)2. Compound 3 shows an unprecedented 3D(4,4)-connected framework with the Point Schl?fli symbol of(64.82)2(65.8). Moreover, the luminescent property of 1 has been investigated.  相似文献   
3.
在水热条件下,利用具有π共轭体系的二羧酸H2L与金属盐进行配位反应得到2个新颖的配位聚合物:{[Mn_2(L)_2(H_2O)_5]·2H_2O}n(1)和[Cd(L)(H_2O)_2]n(2),并通过元素分析、红外光谱、粉末X射线衍射分析、单晶X射线衍射等对其结构进行了表征。结构分析表明,配合物1是具有一维{Mn3(COO)_2}链的二维层状结构,而配合物2中镉离子与L2-配体中的羧基氧螯合配位,最终得到一维链状结构。配合物1和2都通过结构单元之间的氢键作用,最终形成三维超分子结构。此外,还研究了配合物1的磁性和配合物2的光催化活性。  相似文献   
4.
One novel copper(II)-organic compound,namely Cu[Cu2(PP)2](CBPC)2]·2(H2O)(1,H2CBPC = 1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid,HPP = 3-(2-pyridyl)pyrazole),was designed and synthesized under hydrothermal conditions.X-ray diffraction analysis reveals that two Cu(II)ions in the quasi-planar dimmer of [Cu2(PP)2] are linked by the carboxylate oxygen atoms on the phenyl ring and the imidazole ring,respectively,yielding one snake-shaped structure.Magnetic measurements reveal that compound 1 shows the strongly antiferromagnetic property.Crystal data of 1:C58H52Cu3N10O10,Mr = 1239.72,monoclinic,P21/c,a = 14.900(7),b = 15.029(7),c = 12.308(6),β = 102.519(9)o,V = 2691(2)3,Z = 2,Dc = 1.530 g/cm3,F(000)= 1274,μ = 1.246 mm-1,R = 0.0416,wR = 0.0780(I > 2σ(I))and S = 0.999.  相似文献   
5.
One novel cobalt coordination polymer, {[Co(HTCB)(4,4'-btb)]·H2O}n(1, H3TCB= 1,3,5-tris(4-carboxyphenyl)benzene, 4,4'-btb = 4,4'-bis(1,2,4-triazol-3-yl)biphenyl), has been synthesized and characterized by elemental analysis, IR, powder X-ray diffraction(PXRD), and thermogravimetric(TG) analyses. X-ray diffraction analysis reveals that complex 1 is a 2D 2-fold interpenetrated {44,62}-sql [Co(HTCB)(4,4'-btb)] sheet based on the 1D [Co(HTCB)]n chains and1 D [Co(4,4'-btb)]n chains. The crystal of 1 crystallizes in triclinic, space group P 1 with a =9.529(12), b = 13.914(16), c = 14.906(17), V = 1903(4) 3, Z = 2, C45H34N6CoO7, Mr = 829.71,Dc = 1.448 g/cm3, F(000) = 858 and μ(MoKα) = 0.514 mm-1. The final R = 0.0655 and wR = 0.1136 for 6603 observed reflections with I 2σ(I) and R = 0.1136 and wR = 0.1747 for all data.  相似文献   
6.
采用水热法合成了两个新颖的配合物{[Ni(H2qptc)(4,4′-bpy)(H2O)2].2(H2O)}n(1)和[Zn2(H2O)2(qptc)(4,4′-bpy)]n(2)(H4qptc:三联苯-2,5,2′,5′-四羧酸,4,4′-bpy:4,4′-联吡啶),并对其进行了元素分析、热重、红外光谱和、磁性和X-射线单晶衍射测定。化合物1和2都是三维结构,分别显示(65.8)-cds、(42.6)2(43.62.8)(45.64.8)2.拓扑结构。  相似文献   
7.
小兴安岭改造后森林沼泽是兴安落叶松-泥炭藓沼泽经挖沟排水改造而成。测试分析沼泽植物中有微量元素20余种,对植物生长发育最有影响的元素有锰,锌,硼,钴,铜。它们在植物体内的含量有明显差异。但也有共生,即锰-锌-硼-铜-钴。植物各器官的主要微量元素含量亦不同,器官听微量元素含量的时序变化规律明显,随季节变化而变化。  相似文献   
8.
卤化物钙钛矿不仅具有光吸收系数高、激子束缚能低、载流子迁移率高等优异的光电性能,而且具有缺陷容忍度高、低温溶液法生长、带隙可调等传统半导体不具备的优点,迅速成为光电领域的研究热点之一。 在单个光电器件的基础上,开发阵列型器件将推动卤化物钙钛矿在(柔性)光电器件中的应用。 但卤化物钙钛矿因对常规有机溶剂较敏感而与现有光刻工艺不兼容,开发适合卤化物钙钛矿的微纳制作工艺尤为重要。 本文系统归纳了近年卤化物钙钛矿微纳阵列制备采用的各种策略和方法,分析了不同方法的优缺点和适用性,介绍了卤化物钙钛矿微纳阵列在光电领域的应用,并对该领域目前存在的问题及发展前景进行了展望,以期为新型卤化物钙钛矿光电器件的研究提供参考。  相似文献   
9.
范黎明  吕明涛  黄仁忠  高天附  郑志刚 《物理学报》2017,66(1):10501-010501
研究了反馈耦合布朗棘轮中粒子处于负载力、时变外力及噪声作用下的定向输运问题.详细讨论了外力作用时间的不对称性、外势空间的不对称性及外力周期等对反馈耦合棘轮中粒子输运效率的影响.研究发现,外力的时间不对称度能促进反馈棘轮中粒子的定向输运,随时间不对称度的增大,反馈棘轮中粒子能获得较大的效率.然而,外势空间的不对称度能有效抑制耦合棘轮中粒子的扩散,达到增强耦合粒子定向输运的效果.同时还发现,存在最优的噪声强度能使耦合粒子的输运效率达到最大.  相似文献   
10.
One novel entangled cobalt compound,{[Co 3 (nbta) 2 (4,4-bpy) 2 (H 2 O) 2 ](H 2 O) 2 } n (1,H 3 nbta=5-nitro-1,2,3-benzenetricarboxylic acid,4,4-bpy=4,4-bipyridyl),was prepared and characterized by X-ray diffraction,magnetism,elemental analysis,XPS,TGA and IR spectroscopy.The crystal of 1 crystallizes in monoclinic,space group Pc with a=13.0717(16),b=11.4167(14),c=15.9342(19),β=90.5190(10)o,V=2377.9(5)3,Z=2,C 48 H 36 Co 3 N 8 O 20,M r=1221.64,D c=1.706 g/cm 3,F(000)=1242 and μ(MoKα)=1.128 mm-1.The final R=0.0497 and wR=0.1461 for 4185 observed reflections with I > 2σ(I) and R=0.0721 and wR=0.1619 for all data.X-ray diffraction analyses revealed that Co(1) is linked by the nbta 3-ligands to form the ladder shape along the c axis,which is further extended into two-dimensional networks via the joint of Co(2) along the a axis.Moreover,these two dimensional motifs are interconnected by the 4,4-bpy bridges to form a complicated 3-D polymeric framework.Magnetic measurements revealed that compound 1 shows strong antiferromagnetic property.  相似文献   
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