Assessment of Hybrid Density Functionals for the Adsorption of Carbon Monoxide on Platinum Model Clusters

We examined computationally the adsorption of CO on various sites of (111) facets of the model clusters Pt₇₉ and Pt₂₂₅ with the semilocal exchange-correlation functionals PBE, TPSS, and M06L as well as their corresponding hybrid DFT variants PBE0, TPSSh, and M06. The adsorption of CO molecules on Pt(111) is a well-known challenge for the Kohn-Sham DFT approach because one has to treat adequately the electronic structure of the metallic moiety and simultaneously control the self-interaction in the adsorbate. Indeed, in the context of the so-called CO puzzle, hybrid DFT methods do not appear to be beneficial.