The role of Image States in the Charge Exchange between Atom and Metal Surface

Abstract

The paper deals with the role of image states on charge exchange during scattering of Li atom in its ground and excited states (2s,3s,4s) from Cu(111) surface, where we calculate the positive ionization probability of atomic level of the alkali atoms by using the ( ) interaction levels method, in which the Hamiltonian operator is written by Dirac-notations formula and taking into account both life times for atomic levels and image levels. The positive ionization probability of atomic level and final probability are drawn as function to scattering time and the inverse velocity. We note that the effect of image states appear as an oscillations at high velocities in curve. The amplitude of these oscillations differs for different alkali electronic states, which is increase as the energy of the atomic level increasing.