Magnetism in Single Metalloorganic Complexes Formedby Atom Manipulation.

The magnetic properties of molecularstructures can be tailoredby chemical synthesis or bottom-up assembly at the atomic scale. Weused scanning tunneling microscopy to study charge and spin transferin individual complexes of transition metals with the charge acceptor,tetracyanoethylene (TCNE). The complexes were formed on a thin insulator,Cu2N on Cu(100), by manipulation of individual atoms andmolecules. The Cu2N layer decouples the complexes fromCu electron density, enabling direct imaging of the TCNE molecularorbitals as well as spin-flip inelastic electron tunneling spectroscopy.Results were obtained at low temperature down to 1 K and in magneticfields up to 7 T in order to resolve splitting of spin states in thecomplexes. We also performed spin-polarized density functional theorycalculations to compare with the experimental data. Our results indicatethat charge transfer to TCNE leads to a change in spin magnitude,Kondo resonance, and magnetic anisotropy for the metal atoms. [ABSTRACT FROM AUTHOR]