Adsorption and thermal desorption on stepped surfaces

A lattice gas model for the adsorption and thermal desorption on stepped surfaces is formulated with different adsorption sites on the terraces, the lower base and the upper edge of the steps and including various lateral interactions. We employ transfer matrix techniques to get the equilibrium properties, correlation functions and temperature-programmed desorption spectra. A systematic study is presented on the effect of varying terrace widths for atomic, molecular and dissociative adsorption with attractive and/or repulsive lateral interactions. We also present preliminary fits to experimental data on Xe, CO and hydrogen desorption from stepped Pt(111) surfaces. (C) 1998 Elsevier Science B.V.