Benzene adsorption on PtCo(1 1 1): A DFT study

Adsorption benzene on PtCo(1 1 1) surface at low coverage is investigated using density functional theory calculations. We have investigated the PtCo FCT alloy surface with a uniform distribution and two-benzene orientation on the surface. It was found that the most favorable site is a Cosingle bondCo bridge with an adsorption energy of −0.37 eV. A large buckling for the first Co and Pt atoms on the surface layers and a 17–30° H-tilt angles are found. The bonding analysis indicates that Csingle bondC and Csingle bondH bonding increase while Ptsingle bondPt, Cosingle bondCo and Ptsingle bondCo decrease 13.2, 73 and 33%, respectively, after adsorption benzene. The vibrational frequencies of adsorbed benzene were also calculated.