Energy parameters of activation processes in the area of phase transformations in a nanocluster of superionic conductor LaF3

Abstract

The results of quantum chemical calculations of the profiles of intracell potential relief at the elementary disordering act in various parts of the lattice of a crystallite LaF₃ of the size 3.5 × 2.0 × 2.2 nm containing 1200 ions have been presented. For dielectric and highly conductive (HC) phases it has been established that the potential barriers, which limit the movement in the anion sublattice, in the central part of the nanocluster are about 1.5−2.0 times higher than the potential barriers on its faces. It has been shown that for this reason, the efficiency of thermally stimulated motion in the anion sublattice on the faces of a crystallite is several orders of magnitude greater than the efficiency of the movement of fluorine ions in its central regions.