Magnetic properties of single 3d transition metals adsorbed on graphene and benzene: A density functional theory study

We have demonstrated magnetic properties of single 3d transition metal (TM) atom (from Sc to Ni) adsorbed on the surface of graphene and benzene in the framework of relativistic density functional theory. Binding energies, spin and orbital magnetic moments, and magnetic anisotropy energies (MAE) of the TM-graphene and TM-benzene structures were determined. Our calculations show that magnetic moments of most 3d TM atoms added to the surface of graphene and benzene are partially quenched when compared to their free atomic state. We found very robust orbital moments for Co adatom on graphene and benzene and Cr adatom on benzene compared to the almost quenched orbital moments for the other 3d TM adatoms. It is also found that Co-graphene and Co-benzene show very large magnetic anisotropy energies, with easy axis perpendicular to the graphene plane and aligned to the C6 rotation axis of the benzene molecule, whereas the other 3d TM adatoms behave like a soft magnet.