While the dielectric screening response is thus dominated by water reorientation in all methods, we find a FF response ∂∆ϕ w-interface ∂σ = 1 C w-interface that is close to three times as large as compared to the DFT reponse (cf. the different slopes in Fig. ). However, when overall capacitances in vicinity of the PZC are estimated via eq. 3, using C w-interface from Fig. w-interface ∼ -2.4 µF/cm 2 vs C DFT w-interface ∼ -6.8 µF/cm 2 ) and prototypical C bias values from Fig. .