Simple model explaining and predicting coverage-dependent atomic adsorption energies on transition metal surfaces

The adsorption energies of simple atomic adsorbates are coverage dependent. We use density-functional theory to show that the coverage dependence is due to an adsorbate-induced modification of the surface d-band structure. We developed a simple model for predicting the d-band widths of clean and adsorbate-covered metallic surfaces using a tight-binding formalism. The new model can be used in conjunction with the d-band adsorption model to estimate adsorption energies as a function of coverage.