Let us now turn to the dynamics of the systems. Starting from the photo-excitation with a certain excitation energy, the relaxation processes of the systems were described by a series of independent dynamic trajectories in the NA-AIMD simulations. For each polymer, the excitation energy is set to be higher than 3.5 eV, representing a hot exciton excitation in a high-lying excited state, as marked in Fig. , acting as a precursor for polaron-pair states. These trajectories are analyzed by computing the CAE via Eq. ( ) for each trajectory at each 1 fs time step in the respective excited state and then averaging over all trajectories for each polymer. The dynamical evolution of the average CAE is shown in Fig. Analyzing experimental observations with detailed theoretical calculations and theoretical modeling is of great importance for a better understanding of photophysical properties and mechanisms on a microscopic level. Based on our results the experimental findings of Tautz et al. can be substantiated, confirming the CAE as driving force and good quantifier for the exciton recombination rate. The discussion is further extended by the effect that the electrical dipole moment has on charge separation and polaron-pair generation as proposed by Carsten et al. Experimentally it was found that the polymer PCPDT-BDT features a high initial polaron-pair yield followed by a high recombination rate (low lifetime). More- over, PCPDT-BT I was found to have a lower generation of polaron-pairs and also a lower recombination rate (higher lifetime), the latter being favorable for subsequent charge separation. The polymer with the π-spacer lowered both quantities even further and featured long-lived polaron-pair states.