Atomistic computer modelling techniques were used to investigate the substitution of dopants in the CaZrO3 perovskite and the incorporation of protons in the Ba2In2O5 brownmillerite. The defect calculations on CaZrO3 predict that small trivalent cations showed Zr-site selectivity with O vacancy compensation, while larger cations showed Ca-site selectivity with Ca vacancy compensation. EXAFS experiments on doped CaZrO3 demonstrated Yb and Nd substitution at Zr and Ca sites, respectively, in agreement with the simulations. Finally, several water incorporation reactions in Ba2In2O5 were examined, including mechanisms involving O interstitial sites.

Defects and Protons in the CaZrO3 Perovskite and Ba2In2O5 Brownmillerite - Computer Modelling and EXAFS Studies. M.S.Islam, R.A.Davies, C.A.J.Fisher, A.V.Chadwick: Solid State Ionics, 2001, 145[1-4], 333-8