Theoretical exploration on the electronic and magnetic properties of (FeCp) n – (n = 1, 2) ligand-functionalized graphene

Using first principles calculations, we systematically studied the electronic and magnetic properties of half sandwich organometallic ligand-functionalized single layer graphene, (FeCp) n @SLGs ( n = 1, 2), with different adsorption sites and coverage concentrations. Our results show that all the (FeCp) n @SLGs are quite stable having high binding energies. Except the nonmagnetic FeCp@G 44 -S 1 , all the complexes are found to be robust ferromagnets. In particular, the magnetic moments of (FeCp) 2 @G 33 -D 1 , (FeCp) 2 @G 33 -D 2 , (FeCp) 2 @G 33 -D 3 and (FeCp) 2 @G 44 -D 1 per unit cell are as large as 2.0 μ B , 1.64 μ B , 2.0 μ B and 1.30 μ B , respectively. Among the studied systems, spin polarized band gaps are opened in the Dirac points of FeCp@G 33 -S, (FeCp) 2 @G 33 -D 1 , (FeCp) 2 @G 44 -S 2 , (FeCp) 2 @G 44 -S 3 , and (FeCp) 2 @G 44 -D 5 , in which (FeCp) 2 @G 33 -D 1 is transformed into an intrinsic semiconductor. Moreover, displacing Fe by Co or Ni element is found to induce an increasement in magnetic moment or induce a transition from metal to half metal.