A DFT study of hydrogen and carbon monoxide chemisorption onto small gold clusters

DFT calculations have been performed to study the interaction of small gold clusters, Au1–Au13, with H and CO. An odd–even oscillation of the H chemisorption energy was observed, with H adsorption onto odd-numbered clusters being more favourable. This correlates with the smaller HOMO–LUMO gaps for these clusters. For CO chemisorption, the overlap between CO orbitals and cluster frontier orbitals is important. As a result, there is no simple relationship between CO chemisorption energy and the frontier orbital energies of Aun clusters.