Probing superexchange coupling in atomically fabricated d-metal complexes

Magnetic coupling between transition metal atoms that are linked through ligand p-orbitals relies on the virtual exchange of electrons between neighboring sites. The characteristics of the resulting superexchange coupling rely on a complex interplay between electron hopping and Coulomb interaction. In this talk I will review recent experiments on individual superexchange coupled d-metal atoms placed inside a covalent surface network. By using low temperature scanning tunneling microscopy, Fe atoms may be positioned in a Cu$_{2}$N lattice with atomic precision, and their quantum-magnetic properties probed. Our experiments reveal novel insights into the resulting p-orbital mediated magnetic coupling, that are of importance in the fields of molecular magnetism and strongly correlated transition metal oxides.