Charge transfer in atom surface collisions: on the validity of the semi-classical approximation

Abstract The classical limit of the quantum-mechanical theory, describing resonant electron transfer in atom-metal collisions, is studied. It is shown that the charge-transfer process can be described in terms of a classical master equation, if the position of the atomic valence level depends on atom-surface distance z . For the particular case of H − formation on cesiated tungsten (110), the difference between the quantal calculation and the solution of the classical master equation is less than 5%.