▎ 摘 要
Stable configurations, electronic structures, and magnetic behaviors for N, O, and F absorptions on graphene have been investigated by first-principles calculations. It is found that F atom is located just above the C atom, while both O and N atoms are located above the carbon-carbon bond. Strong interactions between absorbers and C atoms exist. N adatom has an unsaturated electron and its electrons are polarized, inducing 0.84 mu(B) magnetic moment per N atom for graphene, while both F and O adatoms do not have polarized electrons, which results in no net magnetic moment. Possible mechanisms were discussed for different magnetic behaviors of graphene absorbed with N, O, and F atoms. We find that the p-type doping of graphene by N atom can result in strongly spin-polarized impurity states, which may lead to a possible pathway to high temperature magnetic order in graphene. (C) 2008 American Institute of Physics.