Localization and bandwidth of the 3d-orbitals in magnetic Ni and Co clusters

Photoelectron spectra of negatively charged Ni-n(-), Cu-n(-), and Co-n(-) c lusters are presented. The spectra of the Ni-n(-) clusters contain informat ion about the degree of localization of the 3d valence orbitals, which is s trongly related to the magnetic properties. In the clusters with less than 7 atoms, the 3d orbitals seem to be almost totally localized. For Co-13(-) we find indications of a narrowing of the 3d-derived valence "bandwidth" co rresponding to a presumed high symmetry and a high degree of degeneracy of the 3d electronic states.