To gain insights about the process timescale and efficiency, and to get a notion about possible impact of nonadiabatic effects on the EDPT process, we investigated the PrdPyr-MeOH photo-relaxation by means of on-the-fly nonadiabatic molecular dynamics simulations. The initial excitation in all three systems targeted the bright S 2 state, with the excitation energy window set to 4.40±0.50 eV, as marked in Figure . In Figure , one can see the mean electronic states' population evolution in time. While all systems start with the pure S 2 state population, a much more efficient relaxation can be observed for PPMet-6 and PPMet-4, than for PPMet-1: firstly, to S 1 (on an ultrafast timescale) and, later, to S 0 . If a monoexponential S 0 population growth is assumed, the characteristic times at which the 50% S 0 population is achieved are 74 fs and 89 fs, respectively for PPMet-4 and PPMet-6. It should be noted that, given the applied E occ -E 0 ≤ 0.20 eV stopping condition, these estimated values represent the lower bound for the process timescale. At the same time, the predicted final S 0 state populations, i.e., populations in the limit of t → ∞, are 77%, 65% and 24% for PPMet-4, PPMet-6 and PPMet-1. The obtained results, on the one hand, give clear manifestation of the much higher reactivity of the reaction center consisting of two neighboring N atoms, than of a single N atom in the pyrazine ring. On the other hand, the final S 0 populations, predicted from the monoexponential fits, suggest that other relaxation mechanisms may play a role on larger timescales. In this respect, radiative or inter-system-crossing induced processes could be considered, which are, however, beyond the scope of the present study. For more details on the performed fitting procedure, including the fitted functions' plots (Fig. ), please refer to the ESI.