EPR parameters and local lattice structure study of V 2+ ions in CdCl 2 and CsMgCl 3 crystals

Abstract

The local lattice structure and EPR parameters ( D, g ‖, g ⊥ ) have been studied systematically on the basis of the complete energy matrix for a d 3 configuration ion in a trigonal ligand field. By simulating the calculated optical and EPR spectra data to the experimental results, the local distortion parameters (Δ R, Δ θ) are determined for V 2+ ions in CdCl 2 and CsMgCl 3 crystals, respectively. The results show that the local lattice structure of CdCl 2:V 2+ system exhibits a compression distortion (Δ R=−0.0868 Å) while that of CsMgCl 3:V 2+ system exists an elongation distortion (Δ R=0.0165 Å). The different distortion may be ascribed to the fact that the radius of V 2+ ion is smaller than that of Cd 2+ ion or larger than that of Mg 2+ ion. Moreover, the relationships between EPR parameter D and local structure parameters ( R, θ) as well as the orbital reduction factor k and g ‐factors (g ‖, g ⊥ ) are discussed.