  We have studied the trends in CO adsorption on close-packed metal surfaces:
Co, Ni, Cu from the 3d row, Ru, Rh, Pd, Ag from the 4d row and Ir, Pt, Au from
the 5d row using density functional theory. In particular, we were concerned
with the trends in the adsorption energy, the geometry, the vibrational
properties and other parameters derived from the electronic structure of the
substrate. The influence of specific changes in our setup such as choice of the
exchange correlation functional, the choice of pseudopotential and size of the
basis set, substrate relaxation has been carefully evaluated. We found that
while the geometrical and vibrational properties of the adsorbate-substrate
complex are calculated with high accuracy, the adsorption energies calculated
with the gradient-corrected Perdew-Wang exchange-correlation energies are
overestimated. In addition, the calculations tend to favour adsorption sites
with higher coordination, resulting in the prediction of wrong adsorption sites
for the Rh, Pt and Cu surfaces (hollow instead of top). The revised
Perdew-Burke-Erzernhof functional (RPBE) leads to lower (i.e. more realistic)
adsorption energies for transition metals, but to wrong results for noble
metals - for Ag and Au endothermic adsorption is predicted. The site preference
remains the same. We discuss trends in relation to the electronic structure of
the substrate across the Periodic Table, summarizing the state-of-the-art of CO
adsorption on close-packed metal surfaces.
