We note that for all our tested oxygen ratios, a geometry optimization with the MACE-MP-0 forcefield also leads to an energy reduction at the DFT level. This reinforces the hypothesis that the Pt 6 O 8 species are most probably an artifact due to the parametrization of the ReaxFF forcefield on specific bulk platinum oxides. In an attempt to explain the saturation regime of oxygen on Pt nanoparticles at high oxygen ratios, we computed the projected density of states (PDOS) of the Pt-5d orbitals (Figure ) and the O-2p orbitals (Figure ) for a range of oxygen ratios.