Molecular dynamics simulations were used to investigate the kinetics and energetics of self-interstitial atom clusters. The formation energies of self-interstitial atom clusters were well represented by a power function with a 0.75 exponent of the cluster size. The cluster diffusivities depended strongly upon their structure. No collective orientational preference of the self-interstitial atom pairs was observed; thus indicating that rotation of several pairs in the cluster was required in order for the cluster to migrate. The activation energy for the rotation was not as high as the cluster migration energy itself.

A Molecular Dynamics Simulation Study of Small Cluster Formation and Migration in Metals. K.Morishita, T.Diaz de la Rubia, E.Alonso, N.Sekimura, N.Yoshida: Journal of Nuclear Materials, 2000, 283-287, 753-7