In the surface oxidation potential region, no charge restraints need to be imposed on the system and the simulation cells are charge neutral. To establish the electrode potential, the experimentally observed and thermodynamically stable compositions of oxygenated adsorbates are installed on the platinum surface. Therefore, the respective number of ions (both K + and F -) to match the free surface charge density σ M are added to the system, see table . Also, the adsorbates on the Pt(111) surface and the H 2 O molecules in the liquid carry charge: If OH * is present on the surface, it is partially charged with -0.16±0.03 e along with atomic oxygen O * carrying a partial negative charge of -0.3 e. Those are compensated by a negligible mean charge on the H 2 O molecules in the water environment of around 0.005 e.