Modeling of Li diffusivity in Li2O by molecular dynamics simulation

In order to understand the Li diffusion behavior in lithium-containing oxides under fusion-reactor conditions, classical molecular dynamics simulation was conducted for Li2O. Fast Li diffusion, namely superionics, was clearly observed at temperatures higher than about half the melting point. In systems containing Li defects such as Li vacancies and Schottky-type defects, Li diffusion was promoted by these defects. It was indicated that both dynamic Frenkel defects, which are thought to induce superionics, and Li radiation defects created as a consequence of Li burn-up play important roles in Li diffusion under fusion-reactor conditions. The role of radiation defects is more significant in a system of higher Li burn-up and lower temperature.