Electron spin resonance and magnetic susceptibility on some copper(II) complexes prepared from phenylazobarbituric and phenylazothiobarbituric acid compounds containing 2,5-dichloro and 2,5-dimethyl groups were discussed. The thio complexes exist in dimer-monomer mixture. The corresponding copper(II) complexes of the oxygen homologous failed to exhibit association. Singlet-triplet separation values equal to -321 and -263 cm-1for the 2,5-dimethyl and 2,5-dichloro complexes, respectively, of the thio series. An empirical measure of the amount of tetrahedral deformation based on the values of g||/A||assigned the square-planar geometry of the dimethyl-oxygen complex while the other complexes are with tetrahedral planar geometries. The effect of temperature on the ESR data was discussed. The diamagnetic properties of the complexes derived from 2,5-dichloro and 2,5-dimethyl thiobarbituric acid suggested the formation of Cu(I) compelxes. © 2004 Elsevier B.V. All rights reserved.
Masoud, M. S., Khalil, E. A., Hafez, A. M., & El-Husseiny, A. F. (2005). Electron spin resonance and magnetic studies on some copper(II) azobarbituric and azothiobarbituric acid complexes. Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy, 61(5), 989–993. https://doi.org/10.1016/j.saa.2004.05.042