Scattering effects and damping of electrons in Pt(111) and Cu(111)

In this work an analysis of experimental and theoretical data associated with the scattering and attenuation of electrons in the Pt(1 1 1) and Cu(1 1 1) crystalline samples is presented. The information about the crystalline structure of the first few atomic layers was obtained by the directional elastic peak electron spectroscopy (DEPES) at the primary electron beam energies E-p from 1.5 keV to 2.0 keV. The comparison of the experimental and theoretical DEPES distributions indicates a qualitative agreement between experiment and theory. The relative signal values associated with the intensity maxima were found to be different. The latter effect suggest that the electron attenuation in the crystalline samples can have an anisotropic character. A qualitative analysis of the characteristic pattern around the [ 1 1 1] direction concerning the calculation of the scattering factors was performed. The collective scattering of electrons by atoms located around the threefold symmetry axis resulting in the so called ring focusing effect is discussed. (C) 2011 Elsevier B. V. All rights reserved.