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991.
由2,2,′,2"-三氨基三乙胺(tren)与N-氧化吡啶醛经席夫碱型缩合,然后还原C=N双键形成的产物为配体(L1),合成了一系列新三角架式过渡金属配合物:[ML12+[M=Mn(Ⅱ)、Ni(Ⅱ)和Zn(Ⅱ)]。利用元素分析、红外光谱、电子光谱和室温磁化率对配合物的结构和性质进行了研究。  相似文献   
992.
三氯化一缬氨酸六水合稀土固体配合物的合成及红外光谱   总被引:6,自引:0,他引:6  
在水溶液中合成了Ln(Val)·Cl_3·6H_2O(Ln=La,Nd,Sm,Gd,Er).利用元素分析和容量滴定法确定了其组成。测定了配合物的红外光谱,对其主要红外吸收带进行了归属。红外光谱结果表明,缬氨酸以内盐的形式存在于配合物中,并通过羟基与稀土离子配位,6个水分子亦参与了配泣,推测La和Nd配合物具有一维无限长锭结构,而Sm、Gd和Er配合物为双核配合物.  相似文献   
993.
A new 1,3,4-oxadiazole-contanining rhenium(I) complex,with the formula [Re(CO)_3(Bphen)(PTOP)],(Bphen=bathophe- nardine,PTOP=4-(5-p-tolyl-1,3,4-oxadiazd-2-yl)pyridine),is synthesized and characterized by elemental analysis,IR,~1H NMR, UV-vis and luminescence spectroscopy.The double-layer electroluminescence devices based on the Re(I) complex have been fabricated by spin-coating technique.The turn-on voltage,maximum efficiency,and brightness for green emission obtained from the devices are 9V,2.1cd/A and 165cd/m~2,respectively.  相似文献   
994.
双金属氰化物配合物的制备、表征及催化性能   总被引:7,自引:0,他引:7  
 制备了基于钴氰化锌的双金属氰化物配合物(DMC)催化剂,并\r\n用元素分析、X射线衍射和红外光谱等手段进行了表征,考察了催化剂\r\n的结构与组成对其催化活性的影响以及该催化体系催化环氧烷烃开环聚\r\n合的特点.结果表明,含ZnCl2和叔丁醇的非晶态DMC催化剂具有最高的\r\n催化活性.该催化体系使聚合物的分子量可控,不饱和度很低(<14μ\r\neq/g),逐步聚合所得到的聚合物的分子量分布较窄(Mn/Mw<1.4\r\n8).13CNMR分析结果表明,甲基氧丙环均聚物的链结构具有无规立构\r\n的特点,且链节分布几乎都为头-尾方式.IR分析结果表明,甲基氧丙\r\n环-环氧乙烷共聚物的链结构是无规分布的.  相似文献   
995.
The stoichiometry of thermal decomposition and enthalpy and structural changes were studied for the compounds formed by penetration of [Ni(4-Etpy)4(NCS)2] (I) into Ca-montmorillonite (II) or Cr-, Zr- and Al-pillared analogues (III, IV and V, respectively). The mass fractions of complex I in II, III, IV or V are different. It was found for all studied compounds that the release of L (L=4-Etpy) is a three-step process (-2L, -1L, -1L), and differences occurred in enthalpy changes (δH in kJ per mole of I) corresponding to the individual processes. These differences and the changes in diffraction and spectral properties of the species formed after intercalation are assumed to have their roots in different intramolecular guest-host interactions in the studied compounds. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
996.
The equilibrium constants and molar absorptivities for the fast formation of a 1:3 complex between cadmium(II) (Cd(II)) and dithizonate anion, in the presence of cationic and non-ionic surfactants, allowed a simple and fast spectrophotometric determination of total cadmium. Indeed, the molar absorptivities of the Cd(II)-dithizone (Dz) complex formed in the presence of the neutral Triton X-100 and cationic cetyltrimethylammonium bromide (CTAB) surfactants are almost twice the value observed in the standard method and the maxima of absorption are shifted by about 40 nm when compared with the standard method. Clearly, the use of neutral and cationic surfactants promotes a higher value of the molar absorptivities of the complex, resulting in an increase in the sensitivity of the method. Application of the method to the desorption of Cd(II) ions from clays is illustrated.  相似文献   
997.
Peaks in collision cross sections are often interpreted as resonances. The complex dilation method, as well as other methods relying on analytic continuation of the scattering formalism, can be used to clarify whether these structures are true resonances in the sense that they are poles of the S‐matrix and the associated Green function. The performance of the Mittag–Leffler expansion and T‐matrix Green function expansion methods are formally and computationally compared. The two methods are applied to two model potentials. Eigenenergies, s‐wave residues, and cross sections are computed with both methods. The resonance contributions to the cross sections are further analyzed by removing the residue contributions from the Mittag–Leffler and Green function expansion sums, respectively. It is suggested that the contribution of a resonance to a cross section should be defined through its S‐matrix residue. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007  相似文献   
998.
The dipole moment and polarizability changes have been determined from electroabsorption (EA) spectroscopy of solid films of fac tris(2-(phenyl)pyridinato,N,C2′)iridium (III) [Ir(ppy)3]. The maximum changes in the dipole moment |Δμ|S=(5.0±0.5) D/f (f is the local field correction factor: 1.3–1.7) accompany ground state to the lowest singlet, and |Δμ|T=(1.7±0.5) D/f ground state to the lowest triplet metal-to-ligand charge transfer (MLCT) excited states formation, while the average polarizability change Å3/f2 follows from the fitting procedure throughout the visible absorption spectrum range. The experimental values of |Δμ| as well as energy positions of the MLCT states correlate with the literature results of time-dependent density functional theory.  相似文献   
999.
The molecular structure of trichloronitromethane has been studied in the gas phase using electron diffraction data. The molecules are found to undergo low barrier rotation about the CN bond with a planar CNO2 moiety in agreement with HF/MP2/B3LYP/6-311G(d,p) calculations. The experimental data are consistent with a dynamic model using a potential function for the torsion of V = (V6/2)(1 − cos 6τ). The major geometrical parameters (rg and ) for the eclipsed form, obtained from least squares analysis of the data are as follows: r(NO3) = r(NO4) = 1.213(2) Å, r(CN) = 1.592(6) Å, r(CCl)av = 1.749(1) Å, Cl5CN/Cl6CN = 109. 6°/106.3°(2), O3NC/O4NC = 117. 6°/114.1°(4), τCl5C1N2O3 = 0.0°, and V6 = 0.20(25) kcal/mol.  相似文献   
1000.
A new flexible ligand, 1,5-bis(8-oxaquinoline)-3-methylpentane (C5MeOQ), was synthesized and used in the preparation of the new dinuclear copper(II) complex 1: [Cu2(μ-OMe)2(μ-C5MeOQ)(NO3)2]. Single crystal X-ray analysis revealed that complex 1 contains dinuclear Cu(II) units with bridging methoxo groups. The ligand, C5MeOQ, takes on a bent conformation in order to connect to and complete the square planar coordination environment of both copper centers; and one of the two Cu(II) centers adopts a distorted square planar configuration as a result of the ligand conformation. The magnetic properties of complex 1 were investigated by variable-temperature magnetic susceptibility measurements in the 100–300 K range. Interestingly, the susceptibility data for complex 1 reveals that the compound is diamagnetic, suggesting the presence of very strong antiferromagnetic coupling interactions between the adjacent Cu(II) centers.  相似文献   
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