First-principles studies on the adsorption of molecular oxygen on Ba(110) surface

The adsorption of O2 on Ba(110) surface is studied with first-principles calculations based on density functional theory. Our calculations predict that O2 may prefer to dissociative adsorption on Ba(110) surface without obvious barrier. Also our results do not support the model of charge transfer from the surface to the molecule as a bond breaking mechanism. Instead, the increasing hybridization between O2 orbitals and the d states of Ba(110) surface may play an important role in the dissociation adsorption.