ABSTRACT
This chapter presents the theory for adsorbates that remain in quasi-equilibrium throughout the desorption process, in which case a few macroscopic variables, namely the partial coverages, and their rate equations are needed. It introduces the lattice gas model and discusses results ranging from non-interacting adsorbates to systems with multiple interactions, treated essentially exactly with the transfer matrix method. The chapter provides examples of the accuracy possible in the modeling of experimental data using this theory for such diverse systems as multilayers of alkali metals on metals, competitive desorption of tellurium from tungsten, and dissociative adsorption of hydrogen on rhodium. It describes the mesoscopic level by outlining recent advances in the theory of the kinetic lattice gas model, such as precursor-mediated adsorption and desorption and the kinetics of adsorption and desorption in the presence of surface reconstruction. The transfer matrix method emerged as an alternative and powerful technique for the study of cooperative phenomena of adsorbates resulting from interactions.
