Thermal Conductivity of Periclase (MgO) from First Principles

We combine first-principles calculations of forces with the direct nonequilibrium molecular dynamics method to determine the lattice thermal conductivity k of periclase (MgO) up to conditions representative of the Earth's core-mantle boundary (136 GPa, 4100 K). We predict the logarithmic density derivative a=(∂lnk/∂lnρ)T=4.6±1.2 and that k=20±5 Wm^-1 K^-1 at the core-mantle boundary, while also finding good agreement with extant experimental data at much lower pressures.