where ∆ 𝑝𝑜𝑡 𝐸(𝑈) represents the influence of the applied potential on the adsorption energy measured vs. the potential of zero charge (PZC). Such potential dependent adsorption energy is usually calculated under the influence of implicit solvation, which also provides a convenient mechanism to approximately account for the associated influence of the neutralizing double layer as the metal electrode is charged. As a validation test, the adsorption of a single water molecule on an Au (111) surface was calculated using Eq. 4 at a variety of applied potentials; one water molecule is described at the DFT level, while remaining water molecules are treated classically, and the potential dependent solute adsorption energy, ∆ 𝑝𝑜𝑡 𝐸(𝑈), is calculated through implicit solvation. Under such circumstances, the adsorption free energy of a water molecule at the interface should be approximately zero at all potentials, as the adsorbing water molecule roughly displaces as nominally identical water adsorbed at the surface. As shown in Fig. , this is in fact roughly observed near the PZC. However, modest deviations from zero do appear at potentials substantially below the PZC, which can be at least partially attributed to the fact that the estimation of the number of displaced water molecules is based on the interaction between neutral metal atoms and water molecules. We note in passing that the water adsorption can change qualitatively in the case of highly charged interfaces, which provides another potential explanation for the deviations away from PZC. We also examined the adsorption of pyridine on a Au (111) with varying potential; a similar system was previously examined by Steinmann et al., who found that the adsorption geometry of pyridine changes as a function of the electrode potential due to the interaction of dipole moments of the adsorbate with the electric field at the interface by using the implicit solvation. However, we find that this potential dependence, at least in the case of large organic molecules, is partly compensated by the corresponding potential dependence of competitive water adsorption. Our results for the pyridine binding energy near the PZC (-32.0 kJ/mol, at ~0.5 V vs SHE) is in good agreement with the experimental results (-37 kJ/mol), whereas the corresponding value in implicit solvent exhibits large, qualitative, error (-74 kJ/mol). Furthermore, the change in adsorption energy between its PZC and a -0.2 V shift is +0.84 kJ/mol based on our model, versus +1.18 kJ/mol as estimated from the experimental data. However, again, care must be taken when the potential of interest deviates considerably from the PZC. Overall, we find that the adsorption energies and geometries at metal/water interfaces can differ substantially from those at metal/gas interfaces, primarily due to the influence of competitive water adsorption. Furthermore, current implicit solvation models qualitatively fail to reproduce the solvation contributions at the metal/water interface, and thus frequently the preferred solute adsorption geometries, due to their fundamental neglect of this effect. Nonetheless, we showed that a simple, phenomenological model, incorporating the influence of competitive water adsorption, can effectively correct this omission and yield semi-quantitative values for adsorption free energies and geometries when applied to standard implicit solvation calculations at metal/water interfaces. The model can also be extended to electrified interfaces, to account for the additional influence of applied potential. We are optimistic that this model will have important impacts in practical computational electro-catalysis calculations, when large scale AIMD calculations are