Self-assembly of point defects into clusters and defect-free regions: a simulation study of higher-valent substituted ferroelectric perovskites

Defect clustering in ferroelectric BaTiO3 modified with higher valent substituents has been simulated using cellular automata with electrostatic energy restriction criteria. Simulations demonstrate a clustering of charged point defects, where defect clusters are randomly distributed with respect to each other. Defect-free regions exist, whose size correlated with that of polar microdomains observed by transmission electron microscopy.