The thermodynamic properties of [beta]-UO3 and [gamma]-UO3

Abstract

Heat capacities of carefully characterized samples of [beta]-UO3 and [gamma]-UO3, have been measured from 5 to 350 K using an adiabatic calorimeter, and from 350 to 700 K by enthalpy increment drop calorimetry. Values for the thermodynamic properties at 298.15 K, CXXX(T), SXXX(T), {HXXX(T)-HXXX(0)} and - {GXXX(T)- HXXX(0)}/T, are for [beta]-UO3: 81.34 J K-1 mol-1, 96.32 J K-1 mol-1, 14682 J mol-1, and 47.062 J K-1 mol-1, respectively, and for [gamma]-UO3: 81.67 J K-1 mol-1, 96.11 J K-1 mol-1, 14585 J mol-1, and 47.179 J K-1' mol-1. respectively.