For both Cz-BDT and Cz-AQ, the ωPBEh functional gives a vertical excitation energy for the lowest bright state at a value in close proximity to the experimental value (indicated as dotted orange line in Figures and). Here, experience suggests that due to vibronic effects, the vertical excitation should be about 0.1 eV above the experimental maximum, therefore indicating excellent agreement of the computed values. Furthermore, ωPBEh succeeds in describing the state characters of the low-energy states involved when compared to the higher-level ri-ADC(2) method and is expected to capture the overall photophysics well. Therefore, we will proceed by using the ωPBEh functional in the further course of the study.