Estimation of conductivity parameters in Sr 1 − xTh xF 2 + 2 x solid solution with fluorite-type structure

Abstract

Concentration of nn-dipoles, nnn-dipoles and charge carriers as well as parameters related to their reorientation and mobility have been estimated from an analysis of a.c. conductivity data of polycrystalline samples of the Sr 1 − x Th x F 2 + 2 x solid solution. The molar fraction of charge carriers has been evaluated as a function of composition. Results obtained confirm, in agreement with the clustering process model, that the (F i) m ions responsible for long range motions in Sr 1 − x Th x F 2 + 2 x are interstitial fluoride ions of F‴ type.