Investigations on the optical absorption bands and the EPR parameters of rhombic cu2+ center in bis(L-asparaginato)zinc(II) crystal

Abstract

In this work, we theoretically study electronic paramagnetic resonance (EPR) parameters (g-factors and A-constants) of the rhombic Cu2 + center in Bis(L-asparaginato)zinc(II) crystal by using the high-order perturbation formulae for these parameters of d9 ion in rhombic octahedral environment from the cluster approach. In these formulae, the contribution to EPR parameters from the ligand orbital and spin–orbit coupling (SO) interactions for the studied Cu2+ center are considered in view of strong covalency. The energy splittings related to the optical absorption spectra are calculated by the superposition model and the local structure of the studied center. On the basis of the studies, the local structure of the center is slightly different from that of the host site due to the Jahn–Teller effect. The calculated results (EPR parameters and optical absorption band positions) are in better agreement with the experimental values than those of previous works.