Molecular dynamics studies of melting: III. Spontaneous dislocation generation and the dynamics of melting

Abstract

The dislocation theory of melting has been further investigated by means of dynamical computer experiments. An f.c.c. Lennard-Jones solid was taken through the melting transition, and it was found that the process is initiated by thermal generation of tiny dislocation loops of the Shockley type. The dislocation density was found to increase steadily during the transition, producing ultimately a system consisting of dislocation cores preferentially arranged as dipole loops, and predominantly in the screw orientation. A simple geometrical interpretation of Lindemann's rule emerges from the model.