Monte Carlo simulation of the adsorbate-assisted adsorption in the case ofCO/ZnO

Recently, a detailed study of the adsorption dynamics of CO on metal oxides , i.e. for the polar ZnO surfaces, has been published [Becker et al., JCP 1 13, 6334 (2000)]. For both polar surfaces, an increase in the adsorption pr obabilities with increasing surface coverage (adsorb ate-assisted adsorptio n) has been observed. A Monte Carlo (MC) version of the so-called modified Kisliuk model is presented, which accounts for the main features observed e xperimentally. The model, which includes two fit parameters, is based on th e differences in the mass mismatch of the gas phase species and the surface s. Therefore, in particular, the polar surfaces of ZnO, which differ by the mass of the atoms in the first surface layer, are perfectly suited for dis cussing the proposed MC algorithm.