Xe adsorption on metal surfaces: First-principles investigations

In the present paper we report in detail the results of our first-principles investigations of Xe/metal adsorption systems which were briefly presented in an earlier publication. We investigate Xe adsorption on the Mg(0001), Al(111), Ti(0001), Cu(111), Pd(111), and Pt(111) surfaces in the (root 3 x root 3)R30 degrees structure. Our calculations are based on density functional theory within the local-density approximation and generalized gradient approximation of Perdew, Burke, and Ernzerhof functions and employing the all-electron full-potential linearized augmented plane wave method. From analysis of the lateral and perpendicular potential-energy surfaces we find that Xe atoms adsorb in the on-top sites in all cases. We identify a noticeable site dependence of the Pauli repulsion, which largely actuates the adsorption site preference. We anticipate that the identified microscopic nature of the binding between Xe and metal atoms may also be valid for other rare-gas atom/metal systems.