CRYSTALLINE ENVIRONMENT OF FE3+ IONS IN HIGHLY MG-DOPED LINBO3 CRYSTAL

The substitutions of Fe3+(I) and Fe3+(II) for both Li+ and Nb5+ ions in LiNbO3 crystal have been studied using the superposition model. From the studies, it is found that a displacement of the impurity ion along the c-axis is required to reach a good fit between the calculated andobsrrved zero-field splittings b(2) degrees. By analyzing the displacement direction from the impurity displacement scheme suggested in this paper, we can conclude that Fe3+(I) replaces Li+ ion and Fe3+(II) replaces Nb5+ ion.