Theoretical study of the electronic properties of fluorographene.

First-principles calculations were performed for fluorine-decorated graphene (fluorographene). Three different hexagonal clusters were used-circular (C(24)H(12)), triangular (C(23)H(10)) and rectangular (C(24)H(12))-and the fluorine atoms were randomly distributed in the mesh. Graphene is structurally stable in the three geometries, but fluorographene stability is only attained for the circular and triangular clusters. Gaps of the circular graphene and the corresponding fluorographene are 2.94 and 1.13 eV, respectively; in the triangular case, the values are zero and 0.47 eV. Both the circular and triangular structures show a transition from ionic to covalent character.