A mathematical model, which was based upon Frenkel's theory of charged-defect segregation at interfaces, was used to calculate the equilibrium grain-boundary depletion layer-widths and conductivity profiles in acceptor-doped ceramics. The calculations modelled the effect of O-vacancy equilibration, during annealing at moderate temperatures (1000K), upon the development of the interfacial charge which affected grain-boundary electrical properties at lower temperatures. Good agreement was found between the model predictions and published experimental results.

Equilibrium Point Defect and Electronic Carrier Distributions Near Interfaces in Acceptor-Doped Strontium Titanate. P.C.McIntyre: Journal of the American Ceramic Society, 2000, 83[5], 1129-36