On kinetic energy distribution of oxygen ion desorbed from CO-adsorbed Ni(110) by time-of-flight type electron-stimulated desorption

Abstract

Kinetic energy distributions of oxygen ions desorbed from CO-chemisorbed Ni(110) surface at 120 K were measured by the time-of-flight technique with various primary electron energies. It is found that the kinetic energy distribution consists of three components. Their desorption mechanisms are ascribed to direct excitation of valence electrons, shake-off excitation including O 1s holes and excitation of C 1s electrons. It is remarkable that the kinetic energy of oxygen ions desorbed by the excitation of C 1s electrons is higher than that by direct excitation of valence electrons.