A DFT study of cyclopropane adsorption on Pt(1 1 1) : electronic structure and bonding

Abstract

We have studied the adsorption of cyclopropane (c-C3H6) on Pt(1 1 1) by means of the density functional theory (DFT). We have investigated the preferential adsorption geometry, considering different adsorption sites and bonding configurations for the molecular adsorbate. We have also computed the electronic structure and bonding interactions by means of density of states (DOS), crystal orbital overlap population (OPDOS), and overlap population (OP) analysis. Our results show a small preference for Bridge and Top adsorption sites with the cyclopropane ring parallel to the surface. PtC equilibrium distance is ∼3.5 Å and a weak bond is formed during adsorption. The main bonding interaction comes from the PtH overlap population. Pt 5pz orbitals play an important role in the bonding between c-C3H6 and the surface. We have found that Van der Waals (vdW) corrections to the energies improve the adsorption values without changing the preferential site geometries.