“…For slow dielectric relaxation, the longitudinal relaxation time of the solvent, L, must be included as the solvent relaxation now happens on the same time scale as the reaction. This observation was first made by Kramers [75], who spoke of a solvent dynamic effect or solvent friction, and the theory was later expanded by authors like Zusman [76,77], Jortner and Rips [61,78,79], Marcus and Sumi [63] as well as several others.…”