EPR parameters and local lattice structure study of V2+ ions in CdCl2 and CsMgCl3 crystals

The local lattice structure and EPR parameters (D, g‖, g⊥) have been studied systematically on the basis of the complete energy matrix for a d3 configuration ion in a trigonal ligand field. By simulating the calculated optical and EPR spectra data to the experimental results, the local distortion parameters (ΔR, Δθ) are determined for V2+ ions in CdCl2 and CsMgCl3 crystals, respectively. The results show that the local lattice structure of CdCl2:V2+ system exhibits a compression distortion (ΔR=−0.0868 Å) while that of CsMgCl3:V2+ system exists an elongation distortion (ΔR=0.0165 Å). The different distortion may be ascribed to the fact that the radius of V2+ ion is smaller than that of Cd2+ ion or larger than that of Mg2+ 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.