Our latest paper exploring properties and oxygen transport in the superionic region of (Thx,Pu1−x)O2 is now available:
- C.O.T.Galvin, M.W.D. Cooper, M.J.D. Rushton and R.W.Grimes, “Thermophysical properties and oxygen transport in (Thx,Pu1−x)O2”, Scientific Reports 6 (2016) 36024. doi:10.1038/srep36024 Open Access PDF
Using Molecular Dynamics, this paper investigates the thermophysical properties and oxygen transport in (Thx,Pu1−x)O2 (0<x<1) between 300–3500K. In particular, the superionic transition is investigated and viewed via the thermal dependence of lattice parameter, linear thermal expansion coefficient, enthalpy and specific heat at constant pressure. Oxygen diffusivity and activation enthalpy are also investigated.
Below the superionic temperature an increase of oxygen diffusivity for certain compositions of (Thx,Pu1−x)O2 compared to the pure end members is predicted. Oxygen defect formation enthalpies are also examined, as they underpin the superionic transition temperature and the increase in oxygen diffusivity. The increase in oxygen diffusivity for (Thx,Pu1−x)O2 is explained in terms of lower oxygen defect formation enthalpies for (Thx,Pu1−x)O2 than PuO2 and ThO2, while links are drawn between the superionic transition temperature and oxygen Frenkel disorder.