A first-principles molecular dynamics simulation of high-temperature proton diffusion in crystalline material was performed. This was the first time that dynamic effects had been explicitly included in simulations of this material. It was found that the diffusion proceeded via a jump-like mechanism. Because of dynamic effects, the diffusion path was substantially different to that deduced from static total-energy calculations. The calculated diffusion coefficient, and its temperature dependence, were in good agreement with available experimental data. It was suggested that scattering experiments could distinguish various diffusion paths.

F.Buda, G.L.Chiarotti, R.Car, M.Parrinello: Physical Review Letters, 1989, 63[3], 294-7