Orbital-specific analysis of CO chemisorption on transition-metal surfaces

We demonstrate that variations in the molecular chemisorption energy on different metals, different surface terminations, and different strain conditions can be accounted for by orbital-specific changes in the substrate electronic structure. We apply this analysis to a density functional theory data set, spanning three metals, two surface terminations, and five strain states. A crucial aspect of our analysis is decomposition of the d band into contributions from the five d atomic orbitals. This provides a representation of the energy levels of the substrate that are directly relevant to the chemisorption bond, leading to strong correlation with chemisorption trends.