Ionic conductivity of fluorite type crystals CaF2, SrF2, BaF2, and SrCl2 at high temperatures

Nanotechnology studies of layered fluoride superionic conductors

“…8. The order of σ at 1,200K coincides with the experiment of Voronin and Volkov [13]. In the other temperatures, the difference with experiments are within single figures.…”

XAFS analyses of molten metal fluorides

“…SrF 2 is of symmetric fluorite crystal structure at low temperature, and undergoes superionic phase below its melting point (1740 K) [18]. XAFS spectra of pure SrF 2 [19] and mixtures with LiF, NaF, and KF (x SrF2 = 20 mol%) at various temperatures have been collected using Sr-K edge.…”

States of the Schottky defect in uranium dioxide and other fluorite type crystals: Molecular dynamics study

“…The specificity of the fluorite-type structure is a very high stability (a low mobility) of the cation sublattice in comparison with the anion sublattice. At high temperatures the anion sublattice exists in a superionic state and the mobility of anions are close to the mobility of ions in melts [1,2]. The diffusion of cations in the crystal lattice of the specified type occurs by the vacancy mechanism via Schottky vacancies [3][4][5].…”

“…In a commonly used approximation of Lidiard and Matzke (see for example [4]) in the model of point defects it is postulated that cation and anion vacancies in a Schottky defect are isolated and do not form any complexes. However, it is known that the point defect model is not able to describe, for example, superionic transition, which was studied well experimentally [1,2] and by the molecular dynamics (MD) method for systems with the fluorite structure. This model is also poorly applicable in general to systems with a high defect concentration and with the strong interaction between defects.…”