The contribution of cluster mobility to low-temperature diffusion in a system of light interstitial impurities was studied by means of computer simulation. It was shown that the magnitude of the contribution was dominated by the parameters of the impurity interaction potential, and the non-monotonic nature of its temperature variation was related to a variation in cluster shape or to freezing-out of one of several mobility mechanisms.

Cluster Mobility in a System of Light Interstitial Impurities. A.A.Berzin, A.L.Morozov, A.S.Sigov: Fizika Tverdogo Tela, 2000, 42[4], 676-8 (Physics of the Solid State, 2000, 42[4], 694-6)