The ionic conductivity of Li‐halide crystals

Abstract The ionic conductivity of mixed crystals of Li halides and Mg halides has been measured. From these measurements the mobility of Li vacancies and the concentration of vacancies in pure Li halides has been derived, with the two assumptions that the defects in Li halides are Schottky defects and the mobility of halide vacancies is negligibly small. The conductivity can be represented by an equation of the form: x = A exp(‐U/kT)[1 + {1 + (4 A′/a 2 ) exp(‐E/kT)}½] in which x is the specific conductivity, U the height of the potential barrier which must be surmounted by the Li + ions when moving through the crystal, E the energy required for the formation of a pair of vacancies, a the concentration of Mg halide and A′ and A constants. The magnitude of E, U, A and A′ (table I) have been compared with theoretical estimates.