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1.
Five thiosalicylic acid (TSA) complexes were prepared. The 1H NMR of these complexes were recorded and analysed. It was found that molybdenum, arsenic, selenium, silver and tellurium metals coordinates through the sulfur atom. The 1H NMR chemical shift of ring protons of As, Se and Te shift to low field upon complexation, while it shifts to high field when TSA complex with Ag and Mo  相似文献   

2.
The electron paramagnetic resonance (EPR) spectra of the trigonal prismatic complexes Tc(abt)3, Tc(bdt)3, Re(abt)3 and Re(bdt)3 (abt, O-aminobenzenethiol; bdt, benzene-1,2-dithiol) in dilute frozen solution are interpreted in terms of an axially symmetric spin Hamiltonian, with g values close to two, principal hyperfine couplings of |A Tc| ~ 5–12 × 10−4 cm−1, nuclear quadrupole couplings of |P Tc| ~ 0.3–0.35 × 10−4 cm−1 and the unusual values 5 × 10−4 cm−1 ~ |A zz Re| < |P Re| ~ |A xx Re| ~ |A yy Re| ~ 25 × 10−4 cm−1. Similar magnitudes of the parameters have been obtained by simulation of the previously published spectra of Re(pda)3, Re(tdt)3 and Re(pdt)3 (pda, O-phenylenediamine; tdt, toluene-3,4-dithiol; pdt, cis-1,2-diphenylethene-1,2-dithiol) by other authors. The unexpectedly large value of P relative to A is a common feature of all the Re tris-dithiolato and related trigonal prismatic complexes studied by EPR and is attributed to the high degree of delocalization of the unpaired electron onto the ligands and the distortion of the electron charge cloud. These factors are less evident in the complexes Tc(abt)3 and Tc(bdt)3. Intermolecular dipolar interactions, narrowed by weak exchange, are responsible for some of the spectral features observed in the solid state and concentrated (≫1 mM) frozen solutions, although there is no evidence for specific solute–solute interactions.  相似文献   

3.
New 99Tc and Re-complexes in colloidal state were prepared by the direct reduction of TcO4- and ReO4- with NaBH4 in presence of a new synthezied ligand: 2,2‘(ethan diylidene dinitrilo) diphenol. The two complexes were precipitated in colloidal forms and characterized by spectroscopy and HPL chromatography. The complexes are H2O soluble.  相似文献   

4.
Through complete neglect of differential overlap (CNDO) calculations of the electronic energy among different possible structures of paracetamol (PA) molecule, it has been concluded that its structure has Cs point group symmetry of the cis‐form in which the methyl group has a restricted free rotation around its bond with the carbon atom of the amide group. The electronic spectra of PA compound were studied in different polar and nonpolar solvents. The temperature effect on the electronic spectra confirms the presence of one conformer only. The hydrogen bonding and the orientation energies of the polar solvents were determined from the studies of mixed solvents. Complexes of PA with metal ions M(II) (Cu++, Zn++, or Fe++) of ratio 2:1, respectively, were prepared, and their structure has been confirmed by elemental analysis, atomic absorption spectra, IR spectra, and 1H‐NMR spectra. It has been concluded that the structure of the complexes has C2h point group symmetry in which two PA molecules are chelated to any one of the metal ions Cu++, Zn++, and Fe++.  相似文献   

5.
《光谱学快报》2013,46(1-2):51-70
New imine–oxime ligands H3L1–H3L3 have been obtained from reactions of the Schiff base ligands H2B1–H2B3 with monochloroglyoxime. Mononuclear copper(II), cobalt(II), nickel(II), vanadyl(IV) and zinc(II) complexes of the imine–oxime ligands H3L1–H3L3 have been prepared and characterized by elemental analyses, infrared and electronic spectra, magnetic moment and molar conductance data. The molar conductance data show that the complexes are non‐electrolytes. When the imine–oxime ligands react with the metal salts in a 2:1 ratio, they behave as dibasic bidentate ligands towards one metal ion. The nickel(II) and zinc(II) complexes are diamagnetic. The 1H(13C)‐nmr spectra of all ligands and nickel(II) and zinc(II) complexes of the ligands H3L1–H3L3 have been recorded. Mass spectra of the imine–oxime ligands and their nickel(II) and zinc(II) complexes were recorded. Some of the ligands and metal complexes have antibacterial activity.  相似文献   

6.
铈与植酸的配合物合成及表征   总被引:1,自引:0,他引:1  
刘泓  杨海峰  曹锋雷 《光谱实验室》2004,21(6):1180-1182
在水溶液中合成了铈 ( 、 )与植酸的固态配合物 ,通过 Raman光谱和荧光光谱方法对其进行了组成分析和性质研究  相似文献   

7.
The synthesis of a new type of complexes of Y, Nd and Er with mono-(2-ethylhexyl) phosphoric acid is reported. The elemental composition, IR-spectral data and thermogravimetric analysis prove the presence of both mono-and bivalent ions of the acid as ligands as well as of NO3-ions. The IR-spectrum is interpreted in comparison with those of other lanthanoid complexes of the same acid.  相似文献   

8.
用已合成且确证其结构的吡啶卟啉季铵盐,合成了它们的金属配合物,通过IR,UV表征了它们的结构.探讨了它们的合成、分离条件及纯化方法.  相似文献   

9.
由氟哌酸根与过渡金属Co(Ⅱ),Ni(Ⅱ),Cu(Ⅱ),Zn(Ⅱ)的氯化物合成了四个未见报道的固态配合物,并用元素分析、红外光谱,热分析表征了它们的组成和性质。  相似文献   

10.
The interaction between Na+, K+, Mg2+ and Ca2+ ions and benzo crown ethers B15C5, DB18C6, DB21C7, DB24C8 and DB30C10 in ethanol solution has been studied spectrophotometrically at 25°C. The formation constants for 1:1 complexes were determined by computer fitting of the resulting UV-absorbance-mole ratio data. In the case of all crown ethers used, K+ ion was found to form the most stable complexes. The observed selectivities of different benzo crowns for the cations used are discussed in terms of the cavity-cation size ratio, number of the donating oxygens participating in the cation binding, conformations of the free and complexed ligands and ionic solvation.  相似文献   

11.
合成了稀土Eu与谷氨酸(Glu)、邻菲罗啉(Phen)形成的三元固体配合物,对其进行了摩尔电导、红外光谱、元素分析的测试,确定其化学组成[Eu(Glu)3phen]Cl3·2H2O,用IR、循环伏安等研究了此配合物的有关性质。  相似文献   

12.
在乙醇溶液中以邻菲咯啉(phen)、2,2’-联吡啶(bipy)和对氨基马尿酸(PAH,HL)为配体与铽离子(Tb(Ⅲ))合成了二元和三元稀土配合物。通过元素分析、差热-热重分析、紫外光谱、红外光谱分析,确定了配合物的组成为TbL3(1)、TbL3·phen·H2O(2)和TbL3·bipy·H2O(3),并讨论了配合物1~3的谱学性质和荧光性能。推测出羧基中的氧原子以桥式双齿的形式与稀土离子配位。由红外光谱和热分析测试确定的配合物1及配合物2中的水分子未参与配位。研究表明,铽配合物在489,583和621 nm处出现发射峰,它们分别归属于5D4→7F6,5D4→7F5,5D4→7F4和5D4→7F3的跃迁。其中544 nm处5D4→7F5跃迁的强度最强,配体的共平面性和共轭性越大,配合物的荧光性能越高,三元配合物TbL3·phen·H2O和TbL3·bipy·H2O的荧光强度优于二元配合物TbL3的荧光强度。  相似文献   

13.
Due to the gradual increase in genetic related disease worldwide, the synthesis, characterization and physicochemical investigation of medicinal compounds such as thiobarbiturates and their derivatives is a highly desired area of research. Keeping their importance as medicinal compounds in mind, herein we report the synthesis and physicochemical characterization of five selected thiobarbiturate samples namely (MKA20 MKA21, MKA22, MKA23, MKA24) by using various physicochemical techniques. All the selected thiobarbiturates and their derivatives were synthesized by the reaction of diethyl thiobarbituric acid with different aromatic aldehydes. The synthesized thiobarbiturates and their derivatives were analyzed by various electroanalytical techniques, which gave us valuable information about the nature of thiobarbiturates and their derivatives. Further, the preliminary interaction of these thiobarbiturate with Deoxyribonucleic acid in aqueous solution was also investigated by using Ultraviolet-Visible spectrometry. On the basis of various results obtained, it can be said that most of their properties and extent of interaction with Deoxyribonucleic acid are varying with changing the alkyl groups on one hand and the functional groups on the other hand.  相似文献   

14.
首次合成丁二酸-1,10-菲啰啉稀土配合物,并运用光谱法研究配合物与DNA之间的作用机制,为新型抗癌药物的设计开发提供依据。以1,10-菲啰啉(phen)和丁二酸(SA)为配体构筑了3种稀土(La3+,Nd3+,Eu3+)配合物,采用元素分析、红外和紫外光谱及热重分析对配合物性质进行表征测试,确定其化学组成为(RE)2(SA)(phen)·2H2O(RE=La,Nd,Eu)。同时,通过光谱法探讨了这3种配合物分别与DNA作用的机理以及稀土离子种类对作用强度的影响。配合物与DNA作用时,可观察到较明显的吸收峰红移和较大的减色效应现象,同时,中性红(NR)荧光竞争实验发现配合物都能不同程度地猝灭NR-DNA体系的荧光。这3种配合物对DNA均具有较强的插入作用,作用强度为:La(Ⅲ)Nd(Ⅲ)Eu(Ⅲ)。计算了DNA与配合物的结合比、结合常数及一些热力学参数,得出DNA与Eu配合物、Nd配合物、La配合物的结合比分别为4∶1,2∶1和8∶1,Δr Gm0、Δr Sm0,表明这3种配合物与DNA之间的反应均能够自发进行,且作用是熵驱动的。  相似文献   

15.
Fourier transform infrared spectroscopy (FTIR), combined with ultraviolet-visible spectroscopy (UV-Vis) and transmission electron micrograph (TEM), has been used to observe the interaction between fulvic acid (FA) and hematite. The FTIR data have shown that the interaction mechanism corresponds mainly to the ligand-exchange involving carboxylic functional groups of the FA and hematite surface sites. The general trends included an increase in the content of Fe(III)-humate complexes on hematite surfaces accompanied by a decrease in pH and an increasing in the ionic strength. Both UV-Vis spectroscopy and TEM images have shown that hematite can interplay with FA under acidic conditions. In particular, the TEM images have shown that the presence of FA can significantly alter the characteristics of the hematite surfaces. Photochemical experiments have shown that hematite promotes the phototransformation of lindane (-HCH), whereas the presence of FA adversely affects the phototransformation of the target pollutant. The hematite coated with FA displayed a somewhat better catalyzing capability compared to the hematite only.  相似文献   

16.
在水-乙醇的混合溶剂中,得到了NO-3参与配位的稀土(RE3+)与2, 3-二甲氧基苯甲酸(2, 3-DMOBAH)及1,10-邻菲咯啉(Phen)的多元混配配合物。通过元素分析确定其组成为RE(2, 3-DMOBA)2NO3Phen(RE=La, Nd, Eu, Dy)。并利用红外吸收光谱,紫外吸收光谱,TG-DTA等对配合物进行了表征。  相似文献   

17.
18.
Optics and Spectroscopy - Optical absorption spectra of 1,2-naphthoquinone in nonpolar (n-hexane) and polar (water) solvents are obtained. It is shown that quantum-chemical time-dependent density...  相似文献   

19.
赵利民  邵鑫  孔营 《发光学报》2009,30(6):862-866
通过对5-磺基水杨酸进行化学修饰并引入偶联基团,同Tb3+配位后与正硅酸乙酯水解缩聚来制备以强化学键结合的光功能杂化材料。利用紫外光谱、核磁共振等来表征中间体和材料的结构。荧光数据表明:材料表现出Tb3+的特征光谱,并具有良好的发光性能。  相似文献   

20.
研究了Nd^3+和Er^3+分别与色氨酸,苯丙氨酸,缬氨酸,咪唑和苯并咪唑配体所组成的配合物,在95%乙醇中的f-f超灵敏跃迁吸收光谱。计算超灵敏峰的振子强度P,电子云伸展比β共价参数δ和键合参数。探讨了配合物的共价性。  相似文献   

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