Abstract
Atomistic computer simulation techniques are applied to the study of defect structure and ion transport in the matlockite-structured phosphor materials PbFCl and LaOBr. The activation energies for a variety of anion vacancy migration mechanisms are calculated and show good agreement with experimental data. The results support the models in which the low-temperature ionic conductivity is attributed to an interplanar chlorine vacancy mechanism. The energetics and ion displacements of self-trapped hole species (Vk centre and O−) in LaOBr are also considered.