Dynamics of molecule-surface interactions from first principles

Abstract

This chapter describes the dynamical studies of molecular adsorption and desorption from metal and semiconductor surfaces based on potential energy surfaces that were derived from first-principles electronic structure calculations. In many cases, these dynamical simulations are in quantitative agreement with available experiments. Still it is the advantage of simulations compared to the experiment that the time evolution of wave packets or trajectories can be followed in any moment. This makes determination and analysis of the crucial qualitative mechanisms governing the interaction dynamics possible. Thus, the high-dimensional simulations based on ab initio electronic structure calculations do not only yield a quantitative but sometimes also a novel qualitative understanding of the adsorption and desorption dynamics. The chapter also discusses the fundamental difference between atomic and molecular adsorption. Whether quantum or classical methods are appropriate for the simulation of the adsorption dynamics or not are discussed in the chapter followed by a short introduction to the determination of potential energy surfaces from first principles and their continuous representation by some analytical or numerical interpolation schemes. The dissociative adsorption and associative desorption of hydrogen at metal and semiconductor surfaces and the molecular trapping of oxygen on platinum are discussed in the chapter.