Potential energy of a single molecules of methanol on graphene at various distances from graphene (open circles, left graph axis). In each calculated point of the curve the atoms of the methanol molecule are allowed to relax according to the forces on the atoms, with the constraint that the center-of-mass position is fixed. The angle that the C-O axis makes with the graphene plane is shown in the curve with solid circles (right graph axis). The insert defines the angle.
