Introducing the Inner Structure of the Magnetic Atom in the Interaction Between a Transition Metal Atom Impurity and a Metal Surface

This paper presents a review of the work performed by the authors to incorporate the inner structure of a d-shell magnetic atom in the description of the many-body interaction between a transition metal atom impurity and a metal host. Two main assumptions are made in this approach: (i) the magnetic atom has an orbital singlet with a total electronic spin S (as corresponds to a case for which the angular moment is quenched); (ii) the first Hund’s rule determines the inner electronic structure of the magnetic atom. Using these two assumptions and the rotational symmetry of the electronic spin, an ionic Hamiltonian is introduced and, in a further step, the effective exchange metal atom coupling and the impurity Kondo temperature are analyzed.