Electronic and structural properties of fluorinated graphene

Experiments have shown that the electronic structure of graphene can be tailored from that of a semimetal to that of a wide bandgap semiconductor through adsorption of fluorene. This makes fluorinated graphene C$_{x}$F (x$\ge $1) attractive for electronics applications. Here we present first-principle calculations that reveal the dependence of C$_{x}$F electronic structure on the degree of fluorination in the range 1 $\le $ x $\le $ 8. We present a systematic analysis of bandgap opening and p-doping, as well as of adsorption energies, lattice constants, bulk modulus and surface corrugation for single-face and two-face functionalization. We rationalize these with a band-interpolation scheme in terms of localized orbitals that clarify the C-C, C-F and F-F bonding. We discuss the relevance of tunable Young modulus for nanomechanical resonators.