The projected density of states were plotted for the different sites, showcasing that each site may contribute to experiment within the uncertainty of the observed σ-and π-levels (Figure ). The atomic site contributes the most intense peaks to the 5σ-(containing hybridization from Pt, O, and C s-, p-, d-orbitals) and 1π-levels (primarily Pt d-orbitals and C, O p-orbitals) of experimental photoemission data, whereas the 4σ-level may represent contributions from all three sites. While the atomic site shifts the 4σ band away from EF, the bridging and hollow sites shift the 4σ band closer to it. Therefore, at higher coverages, the mixing of the bands may shift closer to experimental σ-and π-levels below EF. For the unoccupied LUMO 2π* state, the 2-photon study of Anazawa, et. al. 14 place it at EF + 4.5 eV at <0.17 ML coverage, with a second peak at 4.2 eV rising in prominence as bridging sites become occupied with coverage increasing to θ = ½. QSGW predicts that all three sites can contribute to the 2π* peak at 4.5 eV, so this state cannot be used to discriminate structure. In the PBE + U study by Patra, et. al, the atomic site's most prominent peak was near EF + 3 eV, with a small peak near EF + 4 eV. On the other hand, they found prominent peaks close to EF + 4 eV for the fcc hollow and hcp hollow sites, similar to QSGW results.