Dynamics of adsorprion/desorption of Ne-Cu(111): stiking

The sticking coefficient s of Ne on Cu at substrate temperatures T(s) between 5 and 30 K is computed, within the framework of the same theoretical model as already used for thermal desorption. At very low T(s), s is worked out taking advantage of the proportionality between sticking and desorption rates when desorption is an infrequent event. In this regime, s increases with T(s). At higher T(s) where desorption is not an infrequent event, master equations must be used, and there is no longer proportionality between sticking and desorption rates. In this regime, s decreases with increasing T(s). Calculations for two different potentials fitted to the bound states show that sticking is a much more sensitive probe of the form of the gas-solid potential than thermal desorption fluxes.