To simulate ET processes at the electrode-electrolyte interface, electron density is separately localized on each counterpart. One group of atoms can be considered the electron acceptor while the other group is the electron-donor. These two atomic groups also move at finite temperatures. Such a complete energetic picture of the ET reaction can be studied using the quantum-mechanical constrained density functional theory (CDFT) method in combination with the ab-initio molecular dynamics (AIMD) simulations. Finally, to assess the kinetics of the ET reactions, the Marcus theory 29 can be used. All the parameters of the Marcus model will be computed using the CDFT-AIMD simulations.