Local Density of States Analysis Using Bader Decomposition for N2 and CO2 Adsorbed on Pt(110)-(1 × 2) Electrodes

Local density of states and electric charge in regions defined for individual atoms and molecules using grid based Bader analysis is presented for N(2) and CO(2) adsorbed on a platinum electrode in the presence of an applied electric field. When the density of states is projected onto Bader regions, the partial density of states for the various subregions correctly sums up to the total density of states for the whole system, unlike the commonly used projection onto spheres which results in missing contributions from some regions while others are over counted, depending on the radius chosen. The electrode is represented by a slab with a missing row reconstructed Pt(110)-(1 × 2) surface to model an edge between micro-facets on the surface of a nano-particle catalyst. For both N(2) and CO(2), a certain electric field window leads to adsorption. The binding of N(2) to the electrode is mainly due to polarization of the molecule but for CO(2) hybridization occurs between the molecular states and the states of the Pt electrode.