Having described the states at the ab initio ri-ADC(2) level, it is of interest whether an approximate density functional can be used with the aim of both saving computational time, and to find a method that matches closer with experimental absorption wavelengths. For this purpose, the first five singlet and triplet states for Cz-BDT and Cz-AQ are calculated using TDDFT with the PBE, PBE0, ωPBEh, CAM-B3LYP and ωB97X-V functionals. Figures and (ESI) contain the results for Cz-BDT and Cz-AQ respectively, with the state characters assigned as explained in 4 (a). The experimental absorption maximum is shown as a dashed orange line. The exciton size (d exc ) for the excited state [Eq. 6], an alternative measure for charge transfer, is shown in the bottom panel. In Fig. the functionals are arranged according to an effective increase in Hartree-Fock exchange from left to right: PBE (0%), PBE0 (25%), ωPBEh (20-100%, ω=0.1 bohr -1 ), CAM-B3LYP (19-65%, µ=0.33 bohr -1 ) and ωB97X-V (16-100%, ω=0.3 bohr -1 ) where the amount of Hartree-Fock exchange (HFX) and the range-separation parameter (ω/µ) are given in parentheses. Overall, with increasing HFX we find that the state energies, vertical singlet-triplet gaps, and the oscillator strengths of bright states increase.