Orbital-Specific Modeling of CO Chemisorption

Abstract

We demonstrate that variations in 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. Our density functional theory data set, spanning three metals, two surface terminations, and five strain states, is fit to a single model based on tight binding. A crucial aspect of the model 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 accurate prediction of chemisorption trends.