SUPERPOSITION MODEL ANALYSIS OF ZERO-FIELD SPITTING OF CR3+ ION LITAO3 CRYSTAL

The empirical superposition model (SPM) has been applied to investigat e the substitution of Cr3+ in a LiTaO3 crystal, assuming that the Cr3 ions occupy one of three possible sites: Li+, Ta5+ or structural vaca ncy (SV) sites. The axial zero-field splitting (ZFS) parameter of a Cr 3+ center at a Li site (D-Li), a Ta site (D-Ta), and a SV site (D-SV) was calculated using the SPM. The calculated value of the ZFS D for Cr 3+ at a Li site agrees well with the experimental D value. This allows us to conclude that the Cr3+ replaces the Li+ ion in LiTaO3.