It was recalled that Balluffi and others had long ago presented 3 papers on the nature of the defects which were produced by keV Au bombardment of Au. They noted that vacancy clusters were produced with high efficiency, but could find no evidence of interstitial clusters. These authors had interpreted their data on the basis of replacement collision sequences which carried interstitial atoms beyond the cascade core, leaving behind a vacancy-rich depleted zone which subsequently collapsed into a visible dislocation loop. This situation was simulated here by using molecular dynamics methods which reproduced many of the features which had been reported in 1969. However, there was now a new explanation for the creation of vacancy clusters which was based upon the viscous flow of liquid metal through the irradiated surface.

M.Ghaly, R.S.Averback: Journal of the Physics and Chemistry of Solids, 1994, 55[10], 945-53