Thermal conductivity of UO2 and PuO2 from first-principles

Based on our previously calculated phonon spectra from first-principles, in the present work, we have applied the Slack relation to obtain the thermal conductivity of UO2, PuO2, (Th, Pu) O2, and (U, Pu) O2 in temperature range of 300-1500 K. Also, the mode Grüneisen parameters of PuO2 and UO2 were presented to analyze the anharmonic properties. Rapid decrease of the thermal conductivity for UO2 at low-temperature zone was observed. As for PuO2, its larger phonon group velocity results in better thermal transfer ability than ThO2, UO2, and AmO2 at high-temperature zone.