Simulation of the twin interface in graphite

摘要

The {1121} twin interface in graphite is studied using an analytical model for graphite developed earlier. It is shown that the twin interface, composed of a special atomic geometry ('8-4-8' polygons), can be stable and mobile, which confirms the model previously proposed by Platt (Z Kristallogr 1957;109:226). The simulation study indicates that the {1121} twin interface could consist of a special local atomic structure, namely, the 8-4-8 polygons. The boundary composed of such structure has the energy of 0.09 J/m2 and the activation energy of 3 eV for migration (mostly due to the formation of a kink along the boundary line). The result suggests that existence of a. 8-4-8 structure at the twin interface is not improbable compared to the more widely accepted dislocation model.