Previous works clarified that the capacitance peak in DFT simulations arises from the specific water response to an applied bias, mainly as a result of dielectric saturation and interfacial, electronic polarization (charge transfer) that is strongly influenced by water chemisorption . These effects can be subsumed into a negative, non-linear capacitive component by interfacial water (C w < 0 in eq. 3) which leads to an observed peak and only if C bias is of sizable magnitude. This seems only fulfilled for the DFT simulations ie. the simulations that treat electronic excess charge distributions on a quantum mechanical, electronic structure level. In the following we confirm this core statement by more detailed, subsequent analyses.