The above results demonstrate that in the presence of outer-sphere species, the system and bath electrochemical potentials are no longer equal because the system electrode potential( μM e = E DF T f ) has contributions from the redox couple. As an outer-sphere redox couple is not directly coupled to the electron bath via external connections, such species should not contribute to the electrode potential and variations in electrode potential should only result 1 From exp(-∆G/k B T ) = exp(-∆η/k B T ) and Butler-Volmer equation with symmetry factor 0.5 from inner potential differences, ∆ϕ M through the general definition of Eq. ( ). Therefore, the CIP approach is consistent with the general electrode potential definition whereas electrode potentials inferred from E DF T f do not reflect the electrode material alone but rather the entire simulation system. As ϕ M is not affected by the solution phase redox species and because ∆ϕ M = ∆ϕ bath holds under equilibrium, CIP is expected to correctly mimic the impact of μbath and μM e has led to a misconception that electrode potentials cannot be continuously controlled in GCE-DFT semiconductor simulations, which true only when the system electrochemical potential does not reflect the potential of a single electrode but that of the entire simulation cell. In fact, ground-state DFT is formally an equilibrium theory, which does not support two different Fermi levels within the same simulation cell and introducing bias between electrodes requires utilization of more advanced techniques such as non-equilibrium Green's function methods. . Recent studies have, however,