Electronic and magnetic properties of free and supported transition metal clusters

The spin-polarized relativistic version of the multiple scattering or the Korringa-Kohn-Rostoker method for electronic structure calculations has been used to study the electronic and magnetic properties of free and supported transition metal clusters. Corresponding results are presented for the spin- and spin-orbit-induced orbital magnetic moments in free Fe and FePt clusters. For both systems a pronounced enhancement is found for the spin as well as for the orbital moments compared with the corresponding bulk value which diminishes in an oscillatory fashion with increasing cluster size. Corresponding investigations on small Co clusters deposited on a Pt (111) surface also revealed a strong dependence of the magnetic properties on the cluster size and shape. A comparison of our theoretical results with available experimental data led to rather satisfying agreement.