3d-shell contribution to the energy loss of protons at Cu(111) surfaces

M.S. GRAVIELLE; M. ALDUCIN; J.I. JUARISTI; V.M. SILKIN

Alemania

Conferencia; XXV International Conference on Photonic, Electronic and Atomic Collisions (ICPEAC); 2007

International Conference on Photonic, Electronic and Atomic Collisions (ICPEAC)

Motivated by a recent experimental work [1] we study the contribution of the 3d shell to the energy loss of fast protons scattered off from Cu(111) surfaces. To describe this process we use a multiple collision formalism, in which the interaction of the projectile with 3d electrons is described by means of a sequence of single encounters with atoms belonging to the first atomic layer.     In order to compare the theoretical energy loss with the experimental data, we add the contribution of valence electrons, which is evaluated in linear response theory using a response function that incorporates information on the surface band structure. For completeness, the energy lost by protons is also calculated within a jellium model that includes 3d and valence electrons with equal footing. Fair agreement between theory and experiment is found when the 3d- shell is taken into account in the calculation.