▎ 摘　　要

Computer simulation has been used to study the properties of radiation defects in a graphene sheet Several possible stable configurations of 3D radiation defects in graphene have been simulated Several types of absorbed species were calculated involving a single carbon atom and a dumbbell absorbed at graphene sheet surface and a dumbbell configuration at a vacancy created by radiation knocking out a carbon atom The calculations also included the effect of structural relaxation. The defect caused by the atom being displaced from the structure converted the sheet from metallic to semiconducting (C) 2009 Elsevier B V All rights reserved