Anion self-diffusion was studied by using an isotope exchange technique. These observations were supplemented by ionic conductivity measurements. The results (figure 6) indicated that the dominant defects were Schottky vacancies, with a formation energy of 1.65eV and an anion mobility energy of 0.31eV.

W.S.Rushbrook, L.W.Barr: Journal de Physique - Colloques, 1973, 9, 173-7