TY - JOUR
T1 - Universal magnetic properties of sp3-type defects in covalently functionalized graphene
AU - Santos, Elton J. G.
AU - Ayuela, Andrés
AU - Sánchez-Portal, Daniel
PY - 2012/4/1
Y1 - 2012/4/1
N2 - Using density-functional calculations, we study the effect of
sp3-type defects created by different covalent
functionalizations on the electronic and magnetic properties of
graphene. We find that the induced magnetic properties are universal, in
the sense that they are largely independent of the particular adsorbates
considered. When a weakly polar single covalent bond is established with
the layer, a local spin moment of 1.0 μB always appears in
graphene. This effect is similar to that of H adsorption, which
saturates one pz orbital in the carbon layer. The magnetic
couplings between the adsorbates show a strong dependence on the
graphene sublattice of chemisorption. Molecules adsorbed at the same
sublattice couple ferromagnetically, with an exchange interaction that
decays very slowly with distance, while no magnetism is found for
adsorbates at opposite sublattices. Similar magnetic properties are
obtained if several pz orbitals are saturated simultaneously
by the adsorption of a large molecule. These results might open new
routes to engineering the magnetic properties of graphene derivatives by
chemical means.
AB - Using density-functional calculations, we study the effect of
sp3-type defects created by different covalent
functionalizations on the electronic and magnetic properties of
graphene. We find that the induced magnetic properties are universal, in
the sense that they are largely independent of the particular adsorbates
considered. When a weakly polar single covalent bond is established with
the layer, a local spin moment of 1.0 μB always appears in
graphene. This effect is similar to that of H adsorption, which
saturates one pz orbital in the carbon layer. The magnetic
couplings between the adsorbates show a strong dependence on the
graphene sublattice of chemisorption. Molecules adsorbed at the same
sublattice couple ferromagnetically, with an exchange interaction that
decays very slowly with distance, while no magnetism is found for
adsorbates at opposite sublattices. Similar magnetic properties are
obtained if several pz orbitals are saturated simultaneously
by the adsorption of a large molecule. These results might open new
routes to engineering the magnetic properties of graphene derivatives by
chemical means.
U2 - 10.1088/1367-2630/14/4/043022
DO - 10.1088/1367-2630/14/4/043022
M3 - Article
SN - 1367-2630
VL - 14
SP - 43022
JO - New Journal of Physics
JF - New Journal of Physics
IS - 4
ER -