ESR and optical study of Cu 2+ doped calcium malonate dihydrate

Abstract

The ESR study of Cu 2+ doped calcium malonate dihydrate has been done at room temperature. Four magnetically in-equivalent sites for Cu 2+ have been observed. The spin-Hamiltonian parameters evaluated with the fitting of spectra to rhombic symmetry crystalline field are for Cu 2+ site (I): g x = 2.0963 ± 0.0002, g y = 2.1316 ± 0.0002, g z = 2.4137 ± 0.0002, A x = (32 ± 2) × 10 −4 cm −1, A y = (34 ± 2) × 10 −4 cm −1, A z = (49 ± 2) × 10 −4 cm −1, for site (II): g x = 2.0668 ± 0.0002, g y = 2.0800 ± 0.0002, g z = 2.3561 ± 0.0002, A x = (34 ± 2) × 10 −4 cm −1, A y = (36 ± 2) × 10 −4 cm −1, A z = (51 ± 2) × 10 −4 cm −1, for site (III): g x = 2.0438 ± 0.0002, g y = 2.0623 ± 0.0002, g z = 2.2821 ± 0.0002, A x = (34 ± 2) × 10 −4 cm −1, A y = (36 ± 2) × 10 −4 cm −1, A z = (53 ± 2) × 10 −4 cm −1, and for site (IV): g x = 2.0063 ± 0.0002, g y = 2.0241 ± 0.0002, g z = 2.2357 ± 0.0002, A x = (35 ± 2) × 10 −4 cm −1, A y = (37 ± 2) × 10 −4 cm −1, A z = (54 ± 2) × 10 −4 cm −1. The ground state wave function of Cu 2+ has also been determined. The g-anisotropy has been estimated and compared with the experimental value. Further with the help of optical study the nature of bonding of metal ion with different ligands in the complex has been discussed.