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81.
Crystal Structures of the Terpyridine Complexes [Cd(terpy)Cl2], [Cu(terpy)(CN)Cl], and [Cu(terpy)][Cu(CN)3] · H2O By reaction of cadmium chloride with 2,2′ : 6′,2″-terpyridine (“terpy”) in water/acetone crystals of [Cd(terpy)Cl2] ( 1) were formed. The compound crystallizes monoclinic, space group P21/c, a = 1111.70(10), b = 823.10(7), c = 1643.00(14) pm, β = 93.913(1)°, Z = 4. Starting from mixtures of different molar ratios of copper(II) chloride, terpyridine, and KCN in water/methanole, two complexes of different composition were obtained. At the molar ratio of 1 : 1 : 2 a copper(II) coordination compound with both halide and pseudohalide ligands, [Cu(terpy)(CN)Cl] ( 2 ), was formed which also crystallizes monoclinic, P21/c, a = 1065.6(3), b = 824.6(2), c = 1644.5(7) pm, β = 98.214(3)°, Z = 4. At a molar ratio of 1 : 1 : 10 a partial reduction of copper(II) occured with formation of a mixed valency compound [Cu(terpy)][Cu(CN)3] · H2O ( 3 ) which crystallizes in the hexagonal space group P6522, with a = b = 800.29(1), c = 4771.05(7) pm, Z = 6. Compounds 1 and 2 are structurally similar, the coordination of the metal atoms is square pyramidal. Networks are formed by hydrogen bridges. In 3 the copper(II) ions show a distorted square planar coordination by the three N atoms of the terpy ligand and one N atom of a bridging CN– group, the copper(I) atoms, however, show trigonal planar coordination by three CN– ligands to which the water molecules are bonded by hydrogen bridges. Thus helical chains are formed which stretch in the direction of the screw axes. The EPR spectrum of 3 was measured. 相似文献
82.
Matrix-Investigations on Monomeric Copper(I) Chloride and its Complexes with N2 and PN Ligands. IR Spectroscopic Results and ab-initio Calculation In solid argon the reaction of monomeric CuCl with N2 yields ClCuN2. On the basis of two absorptions in the ir-spectrum and their corresponding isotopic shifts (14/15N) and with the help of a normal coordinate analysis, linearity of the molecule has been deduced. These results are confirmed by large scale ab-initio Calculations (CPF, MP2). Reaction of monomeric CuCl with molecular PN under matrix condition is shown to give rise to new absorptions in the IR spectrum which arev assigned to a linear molecule ClCuNP. 相似文献
83.
84.
Metal sandwich complexes of the classical type M(CnHn)2 and related structural analogs are characterized by a sandwich-like coordination of one central atom by its ligands. This structural principle has been extended in recent years now that di- and tri-nuclear sandwich-type complexes have become accessible. The best-known representatives are the triple-decker sandwich complexes. A survey of this topical field is presented in this report, which also underlines the utility of kinetic and mechanistic studies for the development of new synthetic pathways in organometallic chemistry. 相似文献
85.
酞菁铜固态薄膜的红外光谱 总被引:2,自引:0,他引:2
利用红外透射光谱,偏振透射光谱、掠角反射光谱研究了三-2,4-二特戊基苯氧基8-喹啉氧基酞菁铜LB膜和蒸镀膜的结构。确认在LB膜中,(1)取代基的碳链是以六方晶系或假六方晶系方式堆积的;(2)用偏振红外可以区别苯环上的两个CH2的伸缩振动带。在蒸镀膜中分子基本呈现无序状态。 相似文献
86.
A. El-Toukhy A. F. M. Hefny L. El Sayed M. F. Iskander 《Monatshefte für Chemie / Chemical Monthly》1982,113(2):171-180
The reaction of bis(N-salicylidene)dicarboxylic acid dihydrazides (H4
Lig) with cobalt(II) salts was investigated. Chelates of the types Co(H3
Lig)X ·nH2O, Co2(H2
Lig)X
2, Co3(H3
Lig)2
X
4, Co(H2
Lig) ·nH2O and Co(H3
Lig)2 ·nH2O (X=Cl, Br, I or SCN) were isolated and characterized by their infrared and electronic spectra as well as their magnetic properties.
Koordinationsverbindungen von Hydrazinderivaten mit Übergangsmetallen, 23. Mitt.: Kobalt(II)-Chelate von Bis(N-salicyliden)dicarbonsäuredihydraziden
Zusammenfassung Die Reaktion von Bis(N-salicyliden)dicarbonsäuredihydraziden (H4 Lig) mit Kobalt(II)-Salzen ergab Chelate vom Typ Co(H3 Lig)X ·nH2O, Co2(H2 Lig)X 2, Co3(H3 Lig)2 X 4, Co(H2 Lig) ·nH2O and Co(H3 Lig)2 ·nH2O (X=Cl, Br, I oder SCN). Die Charakterisierung erfolgte mittels IR, Elektronenspektren und magnetischer Eigenschaften.相似文献
87.
Anatoli L. Poznyak Valeri I. Pavlovski 《Angewandte Chemie (International ed. in English)》1988,27(6):789-796
Three types of photochemical reaction of coordination compounds are well-known and have often been discussed: redox reactions, substitutions, and isomerizations. Less well known is a fourth type of reaction, which occurs fairly frequently: reaction of the ligands themselves. It is the purpose of this article to fill the corresponding gap in the photochemical literature and to summarize our current knowledge of such reactions and of their mechanisms and possible applications. 相似文献
88.
Humic acids (HA) are able to interact with a wide range of pollulants and can influence their solubility, transport and bioavailability. In order to study the interaction between polar aromatic hydrocarbons and these macromolecules, an affinity capillary electrophoretic method, the Hummel-Dreyer (HD) method in its modified version, has been used. Two acidic metabolites of phenanthrene: 1-hydroxy-2-naphthoic acid (1-HNA) and 3,4-dihydroxybenzoic acid (3,4-DBA) were studied. The analysis for the binding studies was carried out by injecting a solution of HA in 25 mM ammonium hydrogen carbonate buffer (pH 9) into an uncoated fused-silica capillary, filled with buffer solutions of 1-HNA or 3,4-DBA in varying and increasing amounts. The results obtained indicate that both compounds bind to HA, as had been confirmed by dialysis experiments and literature data. CE proved to be a useful technique for investigating the link between xenobiotics and environmental macromolecules. 相似文献
89.
90.
Rolf W. Berg 《光谱学快报》2013,46(10):715-729
Abstract Vibrational spectra of crystalline powders of [Nien2] [HgI3]2 and [Men2] [HgI4] (where en = ethylene-diamine chelated to M = Ni(II), Pd(II) or Pt(II)) have been measured at room and liquid-nitrogen temperatures. The bands observed in the low frequency region 200–10 cm?1 are interpreted in terms of mainly internal vibrations of the anions and external lattice modes. Raman and far infrared spectra are compared in order to make structural deductions. In comparison with present knowledge of the stereochemistry and vibrational spectroscopy of other iodomercurates, the triiodo-mercurate salt seems to contain nearly planar trigonal anions, while the tetraiodomercurates contain discrete tetrahedra. Probable site symmetries of the anions which may explain the spectra are discussed. 相似文献