First principles study of photoelectron spectra of Cun- clusters.

We have determined equilibrium geometries and electronic properties of neutral and anionic Cu-n (n = 2,9) clusters by means of first principles calculations in which s and d electrons are treated on equal footing. We find that the calculated electronic density of states is inadequate to interpret photoelectron spectra of Cu-n(-) clusters. We obtain good agreement between calculated excitation energies and experimental spectra when we include final states effects.