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Visible-light excitation of a family of bimetallic ruthenium polypyridines with the formula [Ru II (tpy)(bpy)(-CN)Ru II (py) 4 L] n+ (RuRuL n+ ), where L=Cl - , NCS - , DMAP and ACN, was used to prepare photoinduced mixed-valence (PI-MV) MLCT states as models of the photosynthetic reaction center. Ultrafast transient absorption spectroscopy allowed to monitor photoinduced IVCT bands between 6000 and 11000 cm -1 . Mulliken spin densities resulting from DFT and (TD)DFT computations revealed the modulation of the charge density distribution depending on the ligand substitution pattern. Results are consistent with PI-MV systems ranging from non-degenerate Class II to degenerate Class III or II/III, with electronic couplings between 1000 and 3500 cm -1 . These findings guide the control electron localization-delocalization in charge-transfer/charge-separated excited states, like those involved in the photosynthetic reaction center., (© 2024 The Author(s). Chemistry - A European Journal published by Wiley-VCH GmbH.)