We attribute this observation to the fact that in the case of prbimRuPt, the concentration of tpphz-centered excited states is higher in relation to the prbim-centered excited states, i.e., after light excitation, mainly MLCT tpphz states are populated -as anticipated from steady-state results. In the two structurally related systems fbpyRuPt and tbbpyRuPt, on the other hand, excited states with excess electron den-sity on both, the bridging and the peripheral ligands are formed upon excitation at 400 nm. When comparing RuPt photocatalysts to their mononuclear counterparts, they exhibit stronger bridge centered ESA at around 600 nm (see Figure vs. 4d, and further examples in Figure ). This phenomenon can be explained by additional phz-to-phen transitions in the case of the heterobimetallic complexes: In the RuPt photocatalysts the electron density moves from the phz to the phen units of the tpphz ligand, coordinated to both the Ru and the Pt ion. For the herein reported complexes this is supported by TD-DFT (cf. charge density differences in Figure and), predicting for the main ESA band of prbimRu (f (T17) = 0.163) half of the oscillator strength compared to prbimRuPt (f (T20) = 0.315). Furthermore, the 3 MLCT phz state of prbimRuPt shows additional phz-to-phenPt absorption contributions (cf. T39 in Figure ).