FIRST-PRINCIPLES CALCULATIONS OF MOLECULAR DISSOCIATION AT SURFACES

First-principles calculations, using a slab geometry and based on dens ity functional theory, are having an increasing impact on our understa nding of molecule-surface interactions. Calculations of molecular diss ociation at metallic surfaces are briefly reviewed, and results are pr esented for the adsorption and dissociation of O-2 on Ag(110). It is s hown that the calculated properties of the chemisorbed molecule agree well with experiment, but further from the surface there appears to be a significant over-binding, leading to inconsistencies with experimen t.