First-principles study of Ar adsorptions on the (111) surfaces of Pd, Pt, Cu, and Rh

In the present paper we give a detailed report on the results of our first-principles investigations of Ar adsorptions at the four high symmetry sites on M (111) (M = Pd, Pt, Cu, and Rh) surfaces. Our studies indicate that the most stable adsorption sites of Ar on Pd (111) and Pt (111) surfaces are found to be the fcc-hollow sites. However, for Ar adsorptions on Cu (111) and Rh (111) surfaces, the most favorable site is the on-top site. The density of states (DOS) is analyzed for Ar adsorption on M (111) surfaces, and it is concluded that the adsorption behavior is dominated by the interaction between 3s, 3p orbits of Ar atoms and the d orbit of the base metal atoms.