Based on the convergence tests discussed above and those in the Computational Details section, we calculated RPA total energies and GW electronic structures for semimetallic and metallic surfaces relevant to catalysis. We calculated the adsorption energies of H and CO adsorbed to (2×2) Pt( ), H and CO adsorbed to the Pt-group metal free (4×6) FeN 4 active site embedded in graphene, and H adsorbed to (3×3) 1T-MoS 2 . The PBE-relaxed structures of these systems are shown in Figure . We find that RPA can introduce significant shifts to the adsorption in certain cases, but that this is highly system dependent. Table I summarizes these results and shows that the adsorption energy of CO is more affected by RPA than the adsorption energy of H. CO can be destabilized by 0.5 eV from RPA. Notably, we obtain good agreement with literature for the change in CO adsorption energy on Pt(111) due to RPA. RPA correctly predicts the experimentally-observed CO adsorption site ordering, with the atop site being lower in energy than the fcc site, when PBE does not. Finally, our Pt(111) RPA surface energy is predicted to be 1.00 eV/(111 unit area), showing that RPA correctly predicts both the adsorption energy and surface energy. Conversely, we find that H on Pt(111) and FeN 4 @G is destabilized by 0.09 and 0.14 eV, respectively, while it is stabilized by 0.5 eV on 1T-MoS 2 . Again, the GW projected density of states shows a significant shift of the bonding H orbital to energies further below the Fermi level.