X-ray-photoemission-spectroscopy study of the electronic structure of Am metal and AmHx (for x congruent 2)

In order to test the proposal that the anomalous valence-level photemission spectrum of Am results from a divalent (5f7) surface layer, we have performed variable-takeoff-angle experiments on the metal. 4f spectra obtained at 10 degree and 85 degree off normal showed no significant difference in the intensity of the 5f7 (i.e., f-screened) satellite, which is not consistent with an electronically altered surface. Core and valence spectra of a hydrided sample were also obtained for comparison. Pronounced differences in the 5f-derived multiplet manifold were evident, and suggest that alternate screening channels are responsible for the additional features in the metal spectrum. Differences in the metal and hydride 4f peak shapes and satellite intensities are discussed