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1.
《电化学》2016,(3)
环金属钌配合物具有良好的氧化还原和光物理性质,在诸多光电领域如染料敏化太阳能电池、电致变色、电子转移等方面具有重要应用.环金属钌配合物的合成方法主要包括"后期金属化"、"前期金属化"、"转金属化"三种方法.环金属配合物具有丰富的结构多样性.环金属配合物由环金属配体和辅基配体与金属螯合形成.环金属配体包括N^C、N^N^C、N^C^N和C^C^C-类型多齿配体.辅基配体主要包括吡啶、咪唑、三唑、嘧啶等杂环.碳-金属键的引入大大降低了钌配合物的氧化还原电位.通过改变环金属配体和辅基配体的结构,可以对金属的氧化还原电位进行有效调控.金属钌配合物的氧化还原电位对敏化电池的性能以及电子转移的过程具有重要的影响.  相似文献   

2.
环金属钌配合物具有良好的氧化还原和光物理性质,在诸多光电领域如染料敏化太阳能电池、电致变色、电子转移等方面具有重要应用。环金属钌配合物的合成方法主要包括“后期金属化”、“前期金属化”、“转金属化”三种方法。环金属配合物具有丰富的结构多样性。环金属配合物由环金属配体和辅基配体与金属螯合形成。环金属配体包括NC、NNC、NCN和CCC-类型多齿配体。辅基配体主要包括吡啶、咪唑、三唑、嘧啶等杂环。碳-金属键的引入大大降低了钌配合物的氧化还原电位。通过改变环金属配体和辅基配体的结构,可以对金属的氧化还原电位进行有效调控。金属钌配合物的氧化还原电位对敏化电池的性能以及电子转移的过程具有重要的影响。  相似文献   

3.
锰元素不仅在生物化学的酶催化过程中扮演重要的角色.而且在合成分子磁体、开展多核间磁交换作用的研究方面也受到人们的关注.锰配合物的的研究已引起人们的极大兴趣。近年来.我们合成了一些锰配合物.并对其性能进行了初步测定和分析。我们合成的锰配合物.主要集中在芳香羧酸配体体系:为了较系统地研究这类配合物的功能和配体结构的关系.  相似文献   

4.
1,2,4-三唑及其衍生物作为配体与中过渡金属离子能形成多种配合物,这些配合物可表现出良好的生物活性或特殊的电磁性能.因此,过渡金属的三唑配合物的结构和物理特性引起了人们的广泛关注[1-6].  相似文献   

5.
近年来,以双烯酮亚胺基为辅助配体合成金属有机配合物已经引起了化学工作者的广泛关注,其中部分双烯酮亚胺基金属配合物显示出独特的催化反应性能。最近,我们以双烯酮亚胺基为辅助配体合成了一些金属有机配合物,发现具有较大空间位阻的双烯酮亚胺基是合成混配型稀土金属有机配合物的理想配体。进一步研究发现用Na-K合金还原混配型双烯酮亚胺基稀土金属氯化物,  相似文献   

6.
金属-配体间的配位作用是超分子化学中最重要的相互作用之一,寡聚吡啶配体可以与许多过渡金属离子配位,形成具有独特磁、光物理和电化学性质的过渡金属配合物,因此联三吡啶配体过渡金属配合物性能研究引起化学家的广泛关注。本文系统综述了联三吡啶配体及其衍生物的组装策略及其过渡金属配合物的光化学与光物理性能,包括单极、二极及多极配体以及由这类配体组装得到的各种拓扑结构的单核、多核过渡金属配合物,如线型金属寡聚物、金属聚合物、金属大环化合物、有机金属树枝状化合物等,并介绍这些配合物在该领域研究和应用前景。  相似文献   

7.
金属有机配合物的非线性光学特性   总被引:4,自引:1,他引:4  
从过渡金属有机配合物的中心金属、配体和几何结构的多样性、多变的金属氧化态和金属与配体的电子供-受作用评述了金属有机配合物的二阶、三阶非线性光学效应的分子结构特征和最新进展。参考文献26篇。  相似文献   

8.
草酰胺及其衍生物过渡金属原子配合物是近年来在实验和理论上[1 ̄5]研究都十分活跃的领域,其原因是这些配合物具有良好的磁性质,对磁功能分子设计和磁性材料合成有着十分重要的意义。我们课题组合成了一种以N,N′-双(3-羧基水杨醛叉缩胺乙基)草酰胺为配体的Cu!-Cu!均双核配合物,由于该配合物的溶解性较差,难以培养出理想的单晶,因此一直未曾进行晶体结构解析。所以,该配合物分子的电子结构特征和几何构型,电子结构与配合物分子的稳定性及分子的磁性之间的构效关系等目前尚不清楚。因此,就该类磁功能配合物分子的上述问题进行理论研究,无疑…  相似文献   

9.
芳基柔性二齿配体在金属超分子自组装中的结构调控作用   总被引:1,自引:0,他引:1  
芳基柔性二齿佤体的配位构型多变,使得其金属配合物的结构丰富多彩。该文介绍了15种该类配体及其相应的金属配合物的结构与性质和自组装策略,对其在超分子自组装中的结构调控作用作了概述。  相似文献   

10.
咪唑二羧酸类有机配体由于具有多个配位点以及多种配位模式,在构筑配位聚合物方面得到了广泛的研究与应用.由该类配体构筑的配合物种类繁多,结构新颖,迄今已合成了上百种.本文详细概括了咪唑二羧酸类配体的特点、配位模式、配体种类以及相应的配合物,并从烷基取代和芳香基取代两方面综述了这些配合物的发展及其研究现状,同时简述了这类配体构筑的配合物在光学、气体吸附、磁性、催化以及介电方面的性能,最后对这类配体的发展前景进行了展望.  相似文献   

11.
磁场对Schiff碱配合物模拟甲烷单加氧酶催化性能的影响   总被引:1,自引:0,他引:1  
生命体中存在许多双金属酶 ,其结构和作用机制目前尚不清楚 ,为了模拟甲烷单加氧酶的催化作用 ,我们将催化活性较高的金属卟啉、稳定性较高的 Schiff碱及双核结构结合起来 ,设计合成了一系列“类卟啉型”Schiff碱双核配合物 ,并将这些双核配合物模拟酶催化亚碘酰苯 (Ph IO)单加氧化环己烷反应 ,发现其催化活性及抗氧化稳定性类似于四芳基金属卟啉 [1~ 3 ] ;还发现在模拟酶催化环己烷氧化反应中双核配合物中的两个金属离子间存在协同作用 [4 ] .外加磁场对一般热化学反应影响较小 [5~ 7] ,而在催化反应中的磁场效应更明显 [5,8] .为了较…  相似文献   

12.
Copper(II) acetate mediated coupling reactions between 2,6-bis(azidomethyl)pyridine or 2-picolylazide and two terminal alkynes afford 1,2,3-triazolyl-containing ligands L(1)-L(6). These ligands contain various nitrogen-based Lewis basic sites including two different pyridyls, two nitrogen atoms on a 1,2,3-triazolyl ring, and the azido group. A rich structural diversity, which includes mononuclear and dinuclear complexes as well as one-dimensional polymers, was observed in the copper(II) complexes of L(1)-L(6). The preference of copper(II) to two common bidentate 1,2,3-triazolyl-containing coordination sites was investigated using isothermal titration calorimetry and, using zinc(II) as a surrogate, in (1)H NMR titration experiments. The magnetic interactions between the copper(II) centers in three dinuclear complexes were analyzed via temperature-dependent magnetic susceptibility measurements and high-frequency electron paramagnetic resonance spectroscopy. The observed magnetic superexchange is strongly dependent on the orientation of magnetic orbitals of the copper(II) ions and can be completely turned off if these orbitals are arranged orthogonal to each other. This work demonstrates the versatility of 1,2,3-triazolyl-containing polyaza ligands in forming metal coordination complexes of a rich structural diversity and interesting magnetic properties.  相似文献   

13.
胡宗超  卫海燕  王凡  赵琦华  陈志达 《化学学报》2004,62(20):1973-1980,F005
用密度泛函理论结合对称性破损方法(DFF-BS)研究了混合桥联三核镍配合物的磁交换耦合作用.这类化合物是由三唑和异硫氰酸根桥联形成的混合桥配合物.计算表明,在标题化合物中,三唑桥传递反铁磁耦合作用,而异硫氰酸根桥传递铁磁耦合作用;并且,随着异硫氰酸根取代三唑桥的数目增加,配合物的铁磁作用增强,在一定意义上说明了混合桥磁耦合作用的加合性.Mulliken自旋布居分析表明,无论是三唑桥还是异硫氰酸根桥,它们的磁交换作用机理都是磁中心的自旋离域.分子磁轨道分析显示,对于三唑桥,在局域磁轨道之间存在着强的轨道作用,导致了反铁磁耦合;对于异硫氰酸根桥,局域磁轨道之间弱的相互作用,表现了铁磁耦合作用.对标题化合物的研究说明了DFF-BS方法可用于三核体系磁交换作用的研究.  相似文献   

14.
4-Ethylthiosemicarbazide and its NH(1) derivatives have been prepared and confirmed by elemental analysis and 1H?NMR spectra to produce diverse complexes with Co(II), Ni(II) and Cu(II) ions. The obtained complexes have been investigated based on elemental and thermal analyses, spectral (UV/VIS, ESR, mass) studies and magnetic measurements. The IR data reveal the presence of variable modes of chelation for the investigated ligands. The electronic spectra of the complexes as well as their magnetic moments provide information about geometries. The ESR spectra give evidence for the proposed structure and the bonding for some Cu(II) complexes. Thermal decomposition of some complexes ended with metal or metal oxide as a final product.  相似文献   

15.
    
A new Mannich base, N-(1-morpholinobenzyl) semicarbazide (MBS), formed by the condensation of morpholine, semicarbazide and benzaldehyde, and its Cu(II), Ni(II), Co(II) and Zn(II) complexes have been synthesized. Their structures have been elucidated on the basis of analytical, magnetic, electrical conductivity and spectral study as well as elemental analyses. The complexes exhibit square-planar geometry. The monomeric and non-electrolytic nature of the complexes is evidenced by their magnetic susceptibility and low conductance data. The electrochemical property of the ligand and its complexes in acetonitrile solution was studied by cyclic voltammetry. The X-band ESR spectra of the Cu(II) complex in DMSO at 300 and 77 K were recorded and their salient features are reported  相似文献   

16.
Magnetothermal properties of high-spin chloro(2,3,7,8,12,13,17,18-octaethylporphyrinato)manganese(III), chloro(5,10,15,20-tetraphenylporphyrinato) manganese(III), bromo(5,10,15,20-tetraphenylporphyrinato)manganese(III), and (acetato)(5,10,15,20-tetraphenylporphyrinato)manganese(III) complexes as 6% water suspensions were determined by the microcalorimetric method at 298 K in a magnetic field of 0–1.0 T. It was established that when the magnetic field was applied, the temperature of the systems increases, leading to positive values of the magnetocaloric effect: the higher the magnetic field induction, the higher the values. It is shown that the dependences of the heat capacity of the complexes’ solid particles on the magnetic field induction are of an extreme nature with a heat capacity in the area above 0.6 T less than that in the zero field. The regularities of the dynamics of the numerical values of the change in enthalpy and magnetic entropy of the manganese complexes when a growing magnetic field was applied and the regularities of the influence of the acidoligand in pentacoordinated complexes on their magnetothermal properties were considered.  相似文献   

17.
含双噻唑高分子及其螯合物的制备和磁性能研究进展   总被引:2,自引:0,他引:2  
设计和合成有机及高分子磁性材料是当前国内外十分关注的课题,本课题组在先前研究的基础上,以电子理论和磁性理论为指导,从分子设计出发,合成出含双噻唑新型芳杂环聚合物及其过渡金属离子或稀土离子螯合物,测定了它们的磁性能,研究高分子结构、螯合物组成与磁性能的关系,探索产生磁性的机理.发现本研究体系的高分子螯合物具有顺磁居里温度(Tp)高,剩余磁场(Mr)少,矫顽力(Hc)低,是一类很好的软磁性材料,呈现出有一定特色的磁性能.本文综述了含双噻唑高分子过渡金属螯合物、稀土金属螯合物、纳米碳管接枝高分子及其螯合物的制备和磁性能研究,以及典型螯合物的非常规磁性现象的发现和机理探索研究.  相似文献   

18.
New cobalt(II) complexes of the formula [Co(AA)2]X2 (where AA = O-n-propyl-1-amidinourea and O-iso-propylamidinourea, X = Cl or Br) have been synthesized and characterized by elemental analysis, magnetic susceptibility measurements and electronic spectra. The complexes are all violet in colour and posses magnetic moments in the range 4.4–4.5 BM. Electronic spectral and magnetic data identify the complexes as tetrahedral ones. Tetrahedral complexes can only be prepared with O-alkyl-1-amidinoureas containing higher alkyl groups. The electronic spectral data indicate the strong field character of these ligands.  相似文献   

19.
The magnetic and spectral properties of oxovanadium(IV) complexes of bidentate monobasic NO donor Schiff bases derived from 5-chlorosalicylaldehyde, 5-bromosalicyl-aldehyde and aniline are reported. In contrast to an earlier report that the complexes are involved in antiferromagnetic exchange, magnetic, ESR and molecular weight data indicate that the complexes are magnetically dilute. The complexes are monomers. The ESR spectra of the complexes in chloroform solutions show 8-line spectra characteristic of oxovanadium(IV) complexes which are not involved in magnetic exchange. The complexes exhibit magnetic moments in the range 1.73–1.75 B.M. at ~ 295 K and obey the Curie-Weiss law with θ = 0 to + 2 K indicating the absence of magnetic ordering in the temperature range 83–296 K.The electronic and infrared spectral data of the complexes are also reported. In contrast to an earlier suggestion of dimeric structure, a monomeric structure with square-pyramidal geometry is suggested for the complexes.  相似文献   

20.
The influence of nonionogenic, anionic and cationic surfactants on the magnetic relaxation and luminescence properties of gadolinium(III), terbium(III), and dysprosium(III) complexes with p-sulfonatothiacalix[4]arene (TCAS) was studied. It was shown that the presence of both neutral and anionic surfactant does not influence the magnetic relaxation properties of GdTCAS as well as on the luminescence intensity of the TbTCAS and DyTCAS complexes. The presence of cationic surfactant at the concentration less than critical micellar concentration led to the formation of associates with stoichiometric composition with the Tb (Dy, Gd) TCAS complexes. These associates are characterized by more intensive luminescence, as compared to the initial TbTCAS and DyTCAS complexes. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 555–560, March, 2008.  相似文献   

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