Dependence of the electronic and crystal structure of a functionalized graphene on the concentration of chemically adsorbed fluorine

In this paper, we study the change in the fluorine-functionalized graphene layers depending on the fluorine concentration. Ab initio calculations were performed using the density functional theory method in the generalized gradient approximation. It was established that the metallic properties of the graphene layer become semiconducting after functionalization even at low concentrations of chemically adsorbed fluorine $\sim$10 at.%. The band gap increases from 0.11 to 3.09 eV with an increase of the amount of adsorbed fluorine.