Thermal conductivity of crystalline quartz from classical simulations

Abstract

We calculate the thermal conductivity of crystalline $\ensuremath{\alpha}$- and $\ensuremath{\beta}$-quartz in the high-temperature range ($500\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ to $1100\phantom{\rule{0.3em}{0ex}}\mathrm{K}$) using nonequilibrium molecular dynamics simulations and an empirical interatomic potential. We find that finite-size effects associated with the nonequilibrium dynamics are not negligible, which implies that reliable results for the bulk thermal conductivity of quartz must be obtained by extrapolation to infinite sizes. The calculated thermal conductivity is nearly temperature independent over a wide range of temperature, in agreement with experiment.