Activation volumes of oxygen self-diffusion in fluorite structured oxides

In this study, fluorite structured oxides are used in numerous applications and as such it is necessary to determine their materials properties over a range of conditions. In the present study we employ molecular dynamics calculations to calculate the elastic and expansivity data, which are then used in a thermodynamic model (the cBΩ model) to calculate the activation volumes of oxygen self-diffusion coefficient in ThO₂, UO₂ and PuO₂ fluorite structured oxides over a wide temperature range. We present relations to calculate the activation volumes of oxygen self-diffusion coefficient in ThO₂, UO₂ and PuO₂ for a wide range of temperature (300–1700 K) and pressure (–7.5 to 7.5 GPa).