Spectral, thermal and electrical properties of some new azo complexes

Cobalt(ll), nickel(II) and copper(II) acetates react with thymine compound (H2L) to form complexes having the general formula [MH2L(OAC)2(H2O)2]nH2O. However, the interaction of iron(III) chloride with thymine in acetic acid-water medium yields a new complex of the type [FeH2L(OAC)2H2O]OAC.H2O. All the thymine complexes have been characterized by elemental analyses, spectral and magnetic studies where thymine acts as a neutral ligand and the acetate ion behaves as a strong nucleophile during complexation. 6-aryl and thiazolylazo thymine compounds and their metal complexes were synthesized and characterized where the ligands act as a bidentate dibasic. The azo group is not involved in the structure. Thermal decomposition studies of the azo complexes were explained to give more information on the structure of the investigated materials. The effect of some transition metal cations such as Co11, Ni11 and CuII on the electrical behaviour of 6-(2-thiazolylazo)thymine compound is studied. The data obtained obeyed the relation sigma = sigma degrees exp ( - E/2kT) over the temperature range 30-150 degrees C. The observed conductivities of the different complexes follow the order Co < Ni < Cu. It is clear that this trend is depending on the decreasing of the ionic radii and the increasing stability of metal complexes. The calculated mobility of charge carriers is ranged from 10(-5) to 10(-9)cm2/V s suggesting that the conduction of the studied complexes takes place by hopping mechanism.