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

The local lattice structure and EPR parameters (D, g(parallel to), g(perpendicular to)) 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 (Delta R, Delta theta) 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 (Delta R= -0.0868 angstrom) while that of CsMgCl3:V2+ system exists an elongation distortion (Delta R= 0.0165 angstrom). 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, theta) as well as the orbital reduction factor k and g-factors (g(parallel to), g(perpendicular to)) are discussed. (C) 2010 Elsevier Ltd. All rights reserved.