Dynamics of diatomic molecules on metal surfaces: O2/Ag(110) and CO/Ru(0001)

Abstract

This thesis concerns with theoretical modelling from first principles of dynamics of two gas-surface systems (oxygen on silver and carbon monoxide on ruthenium) that are relevant to the heterogeneous catalysis. An accurate potential energy surface is constructed for the interaction of molecular oxygen with the Ag(110) surface based on density functional theory calculations. Using this potential energy surface, the dissociative and molecular adsorption dynamics is studied by performing trajectory calculations. Accuracy of different approximations to exchange-correlation functional in density functional theory for the modelling of the oxygen-silver system is tested. Furthermore, laser induced desorption of oxygen from Ag(110) is studied. Dynamics of carbon monoxide adsorption and scattering on Ru(0001) is also studied by performing trajectory calculations on top of a density functional based potential energy surface. These simulations can explain the results of molecular beam experiments.