PHOTOEMISSION-STUDY OF THE ELECTRONIC-STRUCTURE OF SIZE-SELECTED TRANSITION-METAL CLUSTERS DEPOSITED ON AG(110)

We report on a photoemission study (XPS, UPS) of the evolution of the electronic Structure with cluster size of Ni(n), Pd(n), Pt(n)(n=1-15) mass-selected clusters deposited in submonolayer quantities on a Ag(110) single crystal surface. The monodispersed clusters display individual discrete electronic structure features of the Ni3d, Pd4d and Pt5d emission. With increasing cluster size the increasing splitting between the bonding-like and antibonding-like d-states reflects the molecular interaction. The shift of the center of gravity of the d-state spectrum towards the Fermi energy and its concomittant broadening indicate the trend to transition-metal formation.