It was noted that defect clusters were easily formed in collision cascades in metals and that some of the self-interstitial atoms formed crowdion clusters which diffused via 1-dimensional migration along a close-packed direction. However, defect interactions and thermal fluctuations could cause the direction of the 1-dimensional migration to change so as to result in mixed 1-dimensional and 3-dimensional migration. Kinetic Monte Carlo computer simulations were used to investigate the effects of 1-dimensional, 3-dimensional and mixed migration upon defect-reaction kinetics. Functional relationships were found between the sink strength, the size of the sinks and the average distance between direction changes during mixed migration.

A Kinetic Monte Carlo Study of Mixed 1D/3D Defect Migration. H.L.Heinisch, B.N.Singh, S.I.Golubov: Journal of Computer-Aided Materials Design, 1999, 6[2-3], 277-82