COMPUTER MODELLING OF DEFECTS AND DOPANTS IN MIXED METAL FLUORIDES

This paper describes a computer modelling study of rare earth doping in the mixed metal fluorides LiCaAlF6 , LiSrAlF6 and LiYF4 . All these materials have potential technological applications, providing the motivation to improve understanding of their defect chemistry; in particular the energetics of doping and the sites occupied by dopant ions. Computer modelling is used to calculate the effect of rare earth dopant concentration on the structure of LiYF4 , and to predict the sites occupied by rare earth dopants and the corresponding form of charge compensation, in LiCaAlF6 and LiSrAlF6 .