Structural stability and fission product behaviour in U3Si

The crystalline and amorphous structures of U3Si have been investigated using density functional theory techniques for the first time. The effects of disorder and the impact of fission products has been separated to understand the swelling characteristics of U3Si in both crystalline and amorphous U3Si. Initially, the stability of the three experimentally observed polymorphs of U3Si were explored. Subsequently, we modelled the amorphous U3Si system and conclude that initial increase in volume observed experimentally at low temperature corresponds well with the volume change that occurs with the observed amorphisation of the material. The solubility of Xe and Zr into both the crystalline and amorphous systems was subsequently investigated.