Modelling of Intrinsic Defects in CaYAl3O7.

CaYAl3O7 presents a challenge for computer modelling techniques because of its site-occupancy disorder related to the Ca/Y shared site. Supercells were built to reproduce experimental results which have the best agreement and lowest lattice energy. The potential parameters were obtained by empirical fitting, and reproduced the structure to within 1.09%. Results obtained by supercell and the Mott-Littleton methods were compared. Both methods predict oxygen Frenkel defects are likely to be formed. [ABSTRACT FROM AUTHOR]