title: Embedding transition-metal atoms in graphene: structure, bonding, and magnetism.
abstract: We present a density-functional-theory study of transition-metal atoms (Sc-Zn, Pt, and Au) embedded in single and double vacancies (SV and DV) in a graphene sheet. We show that for most metals, the bonding is strong and the metal-vacancy complexes exhibit interesting magnetic behavior. In particular, an Fe atom on a SV is not magnetic, while the Fe@DV complex has a high magnetic moment. Surprisingly, Au and Cu atoms at SV are magnetic. Both bond strengths and magnetic moments can be understood within a simple local-orbital picture, involving carbon sp(2) hybrids and the metal spd orbitals. We further calculate the barriers for impurity-atom migration, and they agree well with available experimental data. We discuss the experimental realization of such systems in the context of spintronics and nanocatalysis.
authors.affiliation: Laboratory of Physics, Helsinki University of Technology, FI-02015, Finland. akrashen@acclab.helsinki.fi
authors.forename: A V
authors.initials: AV
authors.lastname: Krasheninnikov
authors.forename: P O
authors.initials: PO
authors.lastname: Lehtinen
authors.forename: A S
authors.initials: AS
authors.lastname: Foster
authors.forename: P
authors.initials: P
authors.lastname: Pyykkö
authors.forename: R M
authors.initials: RM
authors.lastname: Nieminen