Theoretical study of the structure of propene adsorbed on Pt(1 1 1)

The interaction of propene on Pt(1 1 1) has been studied using both slab and cluster models and density functional theory methods. The two most stable chemisorbed structures predicted by the slab calculations are equivalent geometries having both the C1–C2 bond parallel to the surface with the centre of this bond above a bridge site. Hence, propene adsorbs on Pt(1 1 1) in a di-σ coordination with the CC double bond parallel to the surface on a short bridge site, in good agreement with the structure suggested from experiment. Results from cluster model calculations carried out for the most stable structure of adsorbed propene are in good agreement with the slab calculations. The binding energy of propene on Pt(1 1 1) is predicted to lie in the ∼0.4–0.5 eV range, in very good agreement with the experimental value.