Coverage dependence of the electronic structure of chlorine adatoms on metal surfaces

The adsorption of Cl on metal surfaces is studied by a first-principles electronic-structure calculation withn the local-density-functional theory as a function of adatom coverage ({Θ}). Hexagonal Cl layers with varying lattice constants are used as adlayers, and the substrate is modeled by the semi-infinite jellium. The work-function change, saturation {Θ} for the adsorption, and the role of metal substrates for these electronic properties are studied through analyses of the calculated charge density, total energy, bond-order, and adatom density of states.