Theoretical and numerical studies of chemisorption on a line with precursor layer diffusion

Models for surface adsorption with mobile precursor states have been studied since the work of Kisliuk to describe gas deposition on a metal surface. As the adsorbate coverage increases, these systems can develop nontrivial correlations that are induced by the diffusion mediated deposition mechanism. Our purpose in this paper is to investigate a model with precursors that is simple enough to be mathematically solved, at least approximately, without completely neglecting the positional correlations between the chemisorbed sites. We consider a model for random deposition of monomers on a line with extrinsic precursor states. In a numeric simulation, we study various quantities describing the evolution of the island structure. We write down the exact kinetic equations for this process and solve these equations within a simple, self-consistent theory that incorporates pair correlations. The results for the correlations, island density number, average island size, and probabilities of island nucleation, growth, and coagulation show good agreement with the simulation data.