Cu 2p X-ray absorption spectroscopy of the metastable Cu/Ag(001) interface

We report a Cu 2p X-ray absorption spectroscopy (XAS) study of Cu pseudomorphic epilayers grown on Ag(001) as a function of the Cu coverage from the sub-monolayer up to similar to 3.6 ML. The thus-probed Cu 3d unoccupied distribution of states local to the Cu sites is found to exhibit a strong similarity in the shape with respect to bcc ultrathin Cu films grown on Fe(001). In addition, the spectra change as the overlayer is progressively increased thereby reflecting the evolution of the structural properties.