ELECTROCHEMICAL STUDY OF CIS-DICYANOBISETHYLENEDIAMINE-CHROMIUM(III) ION AND ITS ADDUCTS WITH HG(II) AND AG(I)

Electrochemical properties of [Cr(CN2)(en)2]+ are described. Reactions of this complex with Hg(II) and Ag(I) were studied. Their stoichiomet ry (1 : 1) was determined using potentiometric and amperometric titrat ions. Differential pulse voltammetry (DPV) was applied to identify the ir products - dinuclear adducts. It was concluded on the basis of DPV experiments that linkage isomerization of bridding cyano ligand occurs in the process of adducts formation. The decomposition (aquation) of these adducts was followed and the influence of H+ and Hg2+ concentrat ion on its rate was measured and discussed. The paper also deals with a spontaneous isomerization of unstable CN linkage isomers Cr(NC)2 and Cr(NC)(CN) to the stable isomer Cr(CN)2.