Surface and interface cerium electronic configuration in Ce/Fe (100)
Laboratoire de Physique du Solide, Université H. Poincaré
BP239 54506 Vandoeuvre, France
2 Laboratoire pour l'Utilisation du Rayonnement Electromagnétique Univerisité de Paris-Sud, F-91405 Orsay, France
Accepted: 17 November 1995
The cerium electronic configuration of very thin films deposited on Fe(100) has been studied by core level photoemission. In the low-coverage regime ( monolayer), cerium atoms are in a trivalent state ( configuration). For larger coverages, cerium atoms exhibit a mixed valent state. This behaviour reflects the valence change of covered cerium atoms at the interface and results from the increase in the hybridization strength for these interface atoms. Owing to an original method, we were able to directly decompose our experimental spectra in two contributions corresponding to the covered (“bulk”) and non-covered (surface) atoms.
PACS: 71.28.+d – Narrow-band systems; heavy-fermion solids; intermediate-valence solids / 79.60.Bm – Clean metal, semiconductor, and insulator surfaces / 73.20.At – Surface states, band structure, electron density of states
© EDP Sciences, 1996