Consequently, the prbim spectator ligands are a curse and a blessing at the same time in terms of employing prbimRuPt for the photocatalytic reduction of protons: On the one hand, they ensure that the initial electron transfer following light excitation occurs unidirectionally onto the bridge connecting the Ru and Pt center. On the other hand, the In contrast, the long-lived state of fbpyRuPt is localized on the fbpy ligands, which are primarily involved in the photoinduced dynamics. electron-rich nature of the prbim ligands causes a stabilization of MLCT phz and destabilization of MLCT prbim states, which in turn prevents the desired Ru-to-Pt electron transfer.