Electron–electron scattering and thermal conductivity of ϵ -iron at Earth's core conditions

The electronic state and transport properties of hot dense iron are of the utmost importance for the understanding of Earth's interior. Combining state-of-the-art density functional and dynamical mean field theories we study the impact of electron correlations on the electrical and thermal resistivity of hexagonal close-packed ϵ -Fe at Earth's core conditions and show that the electron–electron scattering in ϵ -Fe exhibit a nearly perfect Fermi-liquid (FL) behavior. Accordingly, the quadratic dependence of the scattering rate, typical of FLs, leads to a modification of the Wiedemann–Franz law and suppresses the thermal conductivity with respect to the electrical one. The consequence is a significant increase of the electron–electron thermal resistivity, which is found to be of comparable magnitude to the electron–phonon one. (paper)