An examination of the estimation method for the specific heat of TRU dioxides: evaluation with PuO2

This work set out to study the estimation method of the specific heat, Cp, for the dioxides of the transuranic elements. Cp was evaluated as a sum of three terms, contributions of phonon vibration, Cph, dilation, Cd, and Schottky specific heat, Cs, Cph and Cd were calculated using the Debye temperature and Grüneisen constant obtained by high-temperature X-ray diffractometry. The method was applied to PuO2. The estimated Cp was in good accordance with the reported one measured using a calorimeter. The error in the estimation was small compared to that which arises from using the conventional method based on Cp(298) and the melting temperature.