Energetics of the incommensurate phase of krypton on graphite: A computer simulation study.

Abstract

The energetics of the weakly incommensurate phase of a quasi two-dimensional system of 20736 krypton atoms on a graphite surface are investigated. We have chosen a krypton-graphite potential which gives the commensurate phase at the lowest-energy state. The energy increase of the incommensurate phase can be described in terms of an hexagonal domain wall network confirming the phenomenological description byBak et al. [53.9]. The wall energy per unit length £ and the energy associated with each wall intersection A are calculated. Since A is significantly negative our results provide strong evidence that the commensurate-incommensurate transition might be first order.