4f spectral function of cerium in Ce/Fe(100) and Ce/Pd(100) interfaces

Resonant photoemission experiments at the 4d threshold have been carried out in ultra-thin films of cerium deposited on monocrystalline Fe and Pd. In the Ce/Fe system, we have unambiguously demonstrated the reduced Ce configuration admixture in the surface layer by evaporating one monolayer of an appropriate element to suppress the surface contribution. In the Ce/Pd system, the spectra clearly show an exceptional configuration mixture suggesting an intermediate valence regime but they cannot be described in the single impurity Anderson model