Keywords:Lower mantle minerals, Lattice thermal conductivity , Computer simulation , Phonon-phonon interaction , Density-functional theory
Determination of lattice thermal conductivity (κlat) of lower mantle minerals is key to understanding the dynamics of the Earth’s interior. Although it was impractical in the deep Earth pressure (P) and temperature (T) condition for a long time, recent experimental and computational developments have been extending the accessible P and T ranges. We recently succeeded in developing an ab initio technique to calculateκlat at any P and T condition based on the density-functional theory (DFT) combined with anharmonic lattice dynamics theory. The technique was then applied to major end-members of lower mantle minerals, MgSiO3 bridgmanite (Dekura,Tsuchiya,Tsuchiya,2013,PRL) and MgO periclase (Dekura,Tsuchiya,2017,under review). Next we extend our technique to more realistic Fe-bearing minerals in conjunction with the internally consistent LSDA+U technique (Wang,Tsuchiya,Hase,2015,Nature geoscience) to deal with such strongly-correlated systems. In this presentation, we introduce the current situation of our research on κlat .