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 共查询到19条相似文献,搜索用时 109 毫秒
1.
测定了VOSO4与天冬氨酸(asp)和邻菲罗啉(phen)及联吡啶(bipy)三元体系在不同酸度(pH=1-14)的乙二醇-水(1:1)溶液中低温ESR波谱,发现不同pH下生成不同组成和结构的络合物,利用Johnson加合规则并配合IR推测了它们的可能结构,利用电子光谱数据,计算了络合物晶体场参数。  相似文献   

2.
研究了双-(3-二苯基膦丙基)苯基膦铑氯化物Rh(ttP)Cl在不同溶剂中的31PNMR谱。结果表明,该络合物在二氯甲烷或氯仿中的化学位移和耦合常数发生很大改变,而在乙腈、DMF、DMSO等溶剂中则无变化,推测二氯甲烷和氯仿作为Lewis酸和Rh(ttp)Cl反应,生或新络合物,建议在研究金属络合物x-射线衍射结构和NMR数据相关性时应避免使用二氯甲烷和氯仿。  相似文献   

3.
本文通过对[Fe 3O(Ala) 6(H 2O) 3](ClO 4) 7和[Fe 3O(Gly) 6(H 2O) 3](NO 3) 7·3H 2O的ESR谱的解析及变温磁化率的研究,得出它们的ESR谱具有各向同性的特点;朗德因子分别为2.019和1.997;两种配合物中铁离子间有反铁磁相互作用.  相似文献   

4.
《光谱实验室》2002,19(2):153-156
本文通过对[Fe 3O(Ala) 6(H 2O) 3](ClO 4) 7和[Fe 3O(Gly) 6(H 2O) 3](NO 3) 7·3H 2O的ESR谱的解析及变温磁化率的研究,得出它们的ESR谱具有各向同性的特点;朗德因子分别为2.019和1.997;两种配合物中铁离子间有反铁磁相互作用.  相似文献   

5.
本文通过对 [Fe3 O(Ala) 6(H2 O) 3 ](Cl O4) 7和 [Fe3 O(Gly) 6(H2 O) 3 ](NO3 ) 7· 3H2 O的 ESR谱的解析及变温磁化率的研究 ,得出它们的 ESR谱具有各向同性的特点 ;朗德因子分别为 2 .0 19和 1.997;两种配合物中铁离子间有反铁磁相互作用  相似文献   

6.
李勇  郭金梁 《波谱学杂志》1995,12(6):621-626
制备了两种不同基质的掺杂3dZ2基态铜(Ⅱ)苯并15冠5配合物(Cu(Ⅱ)B15C5)的粉末样品,ESR测定结果表明,以B15C5为基质时,Cu(Ⅱ)B15C5的轴向配体是H2O;而以Mg(Ⅱ)B15C5为基质时的轴向配体则是CIO4-.不同的轴向配体对ESR谱的线型有着较大的影响。利用Bleaney公式,计算了键参数,并对成键特性进行了讨论和比较。  相似文献   

7.
Cu^2+—柞蚕丝蛋白络合物的ESR研究   总被引:3,自引:0,他引:3  
纪涛  刘振勤 《波谱学杂志》1989,6(3):277-281
本文用ESR、UV和IR研究了Cu~(2 )-柞蚕丝蛋白络合物,确定了铜的价态及其配位体,给出了化学结构模型,用实验参数计算了配位键参量和配位场能.  相似文献   

8.
本文解析了同位素标记的~(63)Cu-~(14)N-HAP,~(65)Cu-~(14)N-HAP,~(63)Cu-~(15)N-HAP。~(65)Cu-~(15)N-HAP,和Cu-~(15)N-HAP,等五种配合物在四氢呋喃中,在77K温度下测得的分辨较好的ESR波谱。从图上不仅得到了~(63)Cu和~(63)Cu的超精细分裂,而且还得出分辨较好的~(14)N和~(15)N的超超精细分裂。比较合理地确定了g_x,g_y,g_z;A_x~(65),A_y~(65),A_z~(65)和A_x~(63),A_y~(63),A_z~(63)以及A_∥~(15),A_⊥~(15)和A_∥~(14),A_⊥~(14)等张量参数。利用测得的波谱参数计算了键参数,并讨论了配合物的电子结构及成键特性,得到了较满意的结果。  相似文献   

9.
本文研究 Cu( Ⅱ )、含硒氨基酸 (硒代胱氨酸和硒代蛋氨酸 )及其络合物紫外光谱性质 ,探讨了酸度对络合物的影响以及 Cu( Ⅱ )与含硒氨基酸络合物的组成比均为 1∶ 2。  相似文献   

10.
陈炳焕  万谦 《波谱学杂志》1989,6(3):382-385
本文介绍了TE_(011)模式园柱形ESR样品腔的设计方法和作者的一个设计实例.  相似文献   

11.
本文用电子顺磁共振法对某些酸性磷(膦)酸酯VO(Ⅱ)配合物在四氢呋中的氧化过程进行了动力学研究,研究了温度、浓度和配合物性质对反应速度及反应可逆性的影响,并计算得到动力学参数-氧化反应级数,反应速度常数和反应的表观活化能。  相似文献   

12.
测定了VOSO4-谷氨酸(Glu)-邻菲啉(phen)及VOSO4-谷氨酸-联吡啶(bipy)三元混配配合物在不同酸度下(pH=1~14)的乙二醇/水(1:1)溶液中的低温(173K)ESR谱.发现随pH的变化形成各种结构和组成的配合物,利用Johnson的加合规则、结合配合物的IR光谱推测了各种配合物的可能结构;利用电子光谱数据计算了配合物的晶体场多数;讨论了谷氨酸、π受体配合物的成配规律。  相似文献   

13.
B S Prabhananda 《Pramana》1990,34(6):491-506
The “minimum linewidths” seen in the ESR linewidths against temperature plots, the dependence of line widths on the63Cu nuclear magnetic quantum numbers and the Hubbard relation provide sufficient number of equations to determine the anisotropic ESR parameters in the case of axially symmetric Cu(II) complexes even when unresolved hyperfine structures make contributions to linewidths. After testing the method by reanalysing the literature data on Cu(II) bis-acetylacetonate, it has been used to obtain the anisotropic ESR parameters in the case of bis-salicylaldehydate of Cu(II). Linewidth contributions from unresolved hyperfine structures associated with the1H of coordinating CHCl3 inferred in these studies, were confirmed by comparing the widths in CHCl3 and CDCl3 under ideal conditions. The temperature dependence of this contribution and the estimate of rate constant at room temperature (∼ 1010 s−1) suggest that the coordinating solvent exchange is diffusion controlled.  相似文献   

14.
The interaction of iodine as electron acceptor with nortriptyline and imipramine drugs as electron donors has been investigated spectrophotometrically at various temperatures in chloroform and dichloromethane solutions. The observed time dependence of the charge–transfer band and subsequent formation of in solution were related to the slow transformation of the initially formed iodine: drug outer complex to an inner electron donor–acceptor (EDA) complex, followed by fast reaction of the inner complex with iodine to form a triiodide ion. The pseudo-first-order rate constants and activation parameters for the transformation process were evaluated from the absorbance-time data. Stoichiometrices of the complexes were defined by the Job’s method of the continuos variation and obtaind 2: 1 for iodine: drug complexes. The formation constants and molar absorptivities were evaluated from the absorbance-mole ratio data. Thermodynamic parameters of the complexes have been determined from the temperature dependence of the stability constant by Van’t Hoff equation.  相似文献   

15.
Novel tetranuclear Cu(II) complexes in which four Cu(II) ions are arranged in a square planar fashion by four bis(bipyridyl)pyrimidine ligands were investigated by X and Q band ESR in the temperature range 4.2-300 K. The ESR spectra of this grid-like structure were well simulated as rising from triplet species. Analysis of their intensities allowed the spectra to be assigned to the first excited triplet state, and revealed intramolecular antiferromagnetic coupling of the Cu(II) spins. The isotropic exchange interaction J was determined as ?47 K and reducing to about ?5 K on functionalizing the bridging pyrimidine ring at the 2-position by methyl or phenyl. For comparison an ESR investigation was also carried out on the mononuclear analogue Cu(II)—(terpyridine)2 complexes with substituted terpyridine ligands at the 5′ and 5″ position. Depending on the substitutent, the spectra exhibit a static or dynamic Jahn—Teller effect at room temperature. The temperature dependence of their g-values is examined by a modified Silver—Getz model which includes cooperative Jahn—Teller interactions. There is evidence that both an anisotropic spin exchange contribution to D = 0.0159 cm?1 and a coupled (static) Jahn—Teller effect are responsible for efficient coupling between the four Cu(II) ions in the grid complexes with non-substituted pyrimidine bridges.  相似文献   

16.
迄今未见任何稀土氨基酸络合物的ESR波谱报道,本文在合成Gd3+分别与甘氨酸、β-丙氨酸、谷氨酸、天冬氨酸和天冬酰胺五种氨基酸络合物的基础上,测定了不同温度下,水溶液、粉末及分子筛吸附样品的ESR谱,讨论了络合物中晶体场强,对称性及成键特性。  相似文献   

17.
The electronic and magnetic behaviour of the nonsolvated ferric complexes of: (a) meso-tetratolyl-, (b) meso-tetra-4-hydroxyphenyl-, (c) meso-tetra-4-carboxyphenyl-, and (d) 5-(4-carboxyphenyl)-10,15,20-tritolyl-porphyrins was studied by ESR spectroscopy in the temperature range between 300 and 4 K. The complexes exhibit predominant contribution from the low-spin iron species at high temperature and a drastic shift toward the high-spin iron species at the low-temperature limit. These paramagnetic species are in different proportions at different temperatures, as well as in porphyrins with different substituents. The examined porphyrins obtained as disordered solids contain iron complexes with continuous short-range disorder which is additionally sensitive to change of temperature.  相似文献   

18.
本文用电子顺磁共振法对某些酸性磷(膦)酸酯VO(Ⅱ)配合物在四氢呋中的氧化过程进行了动力学研究,研究了温度、浓度和配合物性质对反应速度及反应可逆性的影响,并计算得到动力学参数-氧化反应级数,反应速度常数和反应的表观活化能。  相似文献   

19.
测定了邻香草醛丙氨酸铜配合物在不同状态(固态或溶液)、不同溶剂(CH3OH,DMF,DMSO)及不同温度(室温和150K)下ESR波谱.室温溶液谱观察到二级效应和弛豫效应,藉自旋哈密顿给于了满意解释,由低温溶液谱波谱参数计算了配合物键参数,讨论了成键特性和配合物稳定性.  相似文献   

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