For verifying our structure-potential-relation the structural model of the electrified Pt(111) interface by Huang et al. serves as benchmark. Within their model, the authors include parameter-based submodels for an oxide layer, the water layer and the diffuse layer. They are consequently able to deconvolute the total charge density into contributions arising from Pt oxidation (σ ox ) or hydrogen adsorption and the free surface charge density σ M . σ M itself is associated to the dipole moment of the oxide layer, the water dipole in the interfacial electric field and the pure double-layer charging. In our simulations, the deconvolution is not required as the interface is treated self-consistently. We calculate σ M as the charge den- We have presented two approaches to include the effects of an electrode potential into ReaxFF simulations: First, the double layer potential region (up to 0.5 V) is installed over the potential-defining free charge densities on the adsorbate-free Pt(111) surface. Second, in the surface oxidation potential region (0.65-1.0 V) the stable coverages of oxygenated intermediates on the Pt(111) surface define the free surface charge density and correlate to a specific electrode potential.