Overall, the emission of prbimRu is quenched by 97 % when comparing to the dinuclear system prbimRuPt. The respective extent of quenching in the structurally related complexes tbbpyRu and fbpyRu is 95 % and 28 %, respec-tively. In line with the results of Sakai et al. we would therefore anticipate a very different photocatalytic behavior for all three complexes, with prbimRuPt showing the highest photocatalytic potential. Nonetheless, we found that prbimRuPt is inactive with respect to photocatalytic proton reduction (see section Photocatalytic hydrogen evolution). We associate this with the photoinduced dynamics of prbim-RuPt (see section B). In contrast to tbbpyRu and fbpyRu, the peripheral ligands are not involved in the photoinduced processes, which solely occur on the tpphz bridge.