First-principles calculations of Xe-adsorbed Pd(111) and Cu(111) surfaces with an empirical correction of van der Waals interactions

The adsorptions of Xe atoms on the Pd(111) and Cu(111) surfaces are investigated by first-principles calculations. The van der Waals interactions are considered in the optimization of the geometric structure. The equilibrium distance from the Xe atom to the topmost surface layer and the rumpling of the substrate are closer to the experimental data than by conventional calculations without including van der Waals interactions. The existence of the induced states, which are partially filled by electron back donation, is predicted by the calculated local density of states. The mechanism of the sublevel splitting of the 5p(3/2) states is discussed. The differential electron densities are used to analyze the electron redistribution by the adsorption of Xe atoms. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3660425]