ESM-RISM calculations have been carried out using the Quantum Espresso software (7.2). We used the pseudopotentials from the SSSP efficiency library, that is pslibrary 0.3.1 for O (6 valence electrons: 2s 2 2p 4 ), pslibrary 1.0.0 for H (1 valence electron: 1s 1 ), but deviated from the recommended GBRV 1.4 library for Pt, where instead the SG15 norm-conserving pseudopotential 70 (18 valence electrons: 5s 2 5p 6 6s 2 5d 8 ) was used. For RISM calculations, switching to this pseudopotential, reduced the initial charge sloshing behavior, and lead to a much smoother convergence. The associated energy cutoff was set to 815 eV. The Pt(111) surface is represented by a 3×3 slab and a √ 3 × √ 3 R45 slab both consisting of five layers for 1/9 ML and 1/3 ML coverage calculations respectively.