The defect chemistry of oxides was analyzed for temperatures at which the O exchange equilibrium reaction was no longer reversible but the internal ionization equilibrium reactions were still reversible. The defect concentrations at such a temperature could be derived numerically as well as analytically. It was pointed out that low-temperature defect chemistry offered a quantitative basis for the manipulation of charge carrier and defect concentrations.

Low Temperature Defect Chemistry of Oxide Electroceramics. K.Sasaki, J.Maier: Key Engineering Materials, 1999, 169-170, 189-92