  {\alpha}-particle irradiated single-crystal isostructural oxide lattices
(CmO2, AmO2, CeO2, UO2, NpO2, PuO2, ThO2) were modeled by molecular dynamics
simulation method. Lattice parameter changes with IFP cation defects displayed
exponential increases. These data were compatible with the available lattice
parameter changes with {\alpha}-particle dose experiments. Pre- and post- peaks
emerged around principal peaks of irradiated oxide cation-cation radial
distribution functions, which indicate obstruction and distortion type defects,
respectively. Dependence of lattice dilatations on the number of obstruction
type cation defects was examined. In a previous study, obstruction type uranium
defects were found to be directly responsible for the UO2 lattice swelling and
there was a linear relationship between them. It was also determined that this
linear equation has two different slopes at low and high defect concentrations.
In this paper, it was found that these phenomena were not specific to UO2 and
applicable to all fluorite-structured actinide and lanthanide dioxides studied
here. These findings provide clues about the existence of more general law.
