  Radiation defects generated in various nuclear materials such as Mo and CeO2,
used as a surrogate material for UO2, formed by sub-MeV Xe and Kr ion
implantations were studied via TRIM and MD codes. Calculated results were
compared with defect distributions in CeO2 crystals obtained from experiments
by implantation of these ions at the doses of 1\times10^17 ions/cm2 at several
temperatures. A combination of in situ TEM (Transmission Electron Microscopy)
and ex situ TEM experiments on Mo were used to study the evolution of defect
clusters during implantation of Xe and Kr ions at energies of 150-700 keV,
depending on the experimental conditions. The simulation and irradiation were
performed on thin film single crystal materials. The formation of defects,
dislocations, and solid-state precipitates were studied by simulation and
compared to experiment. Void and bubble formation rates are estimated based on
a new mesoscale approach that combines experiment with the kinetic models
validated by atomistic and Ab-initio simulations. Various sets of quantitative
experimental results were obtained to characterize the dose and temperature
effects of irradiation. These experimental results include size distributions
of dislocation loops, voids and gas bubble structures created by irradiation.
