Dissociation pathways of oxygen on copper (110) surface: a first principles study

We have carried out first principles calculations to examine the adsorption and dissociation of oxygen on the Cu (1 1 0) surface. At low coverage, our results indicate two absorption species: a peroxo- and a superoxo-like spe cies which have direct implications to the dissociation process. In agreeme nt with experimental studies, the most favourable absorption site for O-2 i s found to be the 4-fold hollow site. The dissociation barrier at this site is only 150 meV, which is consistent with experimental findings. Static ca lculations also reveal other possible dissociation pathways with significan tly different energy barriers. First principles MD simulations are used to probe the dynamics of the dissociation process. We find only selected pathw ays are likely to be utilised because of interaction with the surface. (C) 2000 Elsevier Science B.V. All rights reserved.