PhenPer shows vibrationally resolved emission between 430 and 550 nm (see Fig. ) originating from the S1 → S0 transition on the Per unit (see Fig. ). The features of phenPer are redshifted (by 0.1 eV) compared to Per, due to the π-extension by the phen-unit (see CDDs in Tab. S3). The charge-transfer character of the S1 state in phenPer also reduces the fluorescence quantum yield in phenPer (53%) with respect to Per (98%). Upon coordination of Rh III to phenPer the perylene emission is quenched entirely, hinting to excited-state electron transfer to the metal center. This is consistent with previous findings on Ru II Rh III molecular dyads or polymeric Rh III architectures. Likewise, addition of the sacrificial electron donor triethylamine (TEA) quenches the emission of phenPer (dynamic and static quenching, Stern-Volmer constant of 2.5 -9.7 M -1 , see Fig. ). Hence, phenPer is capable of being photochemically reduced. Photoinduced Dynamics. To characterize the ultrafast photoinduced processes, femtosecond transient absorption (fs-TA) spectra of Rh III phenPer and phenPer in acetonitrile were collected upon excitation at 400 nm (see Fig. , S16 and S17). The TA spectrum of phenPer recorded as benchmark shows excited state absorption at wavelengths longer than 550 nm (λmax = 706 nm) 23 accompanied by ground state bleach (GSB) at 435 nm and stimulated emission (SE) features at 474 and 515 nm (at a delay time of 0.5 ps, see Figure ). This is consistent with the TA spectra of Per-derivatives. Global kinetic analysis of the TA data reveals three characteristic time-constants describing the decay of the signal, i.e. τ1 = 1.7±0.3 ps, τ2 = 68±5 ps and τ3 = 2.9±0.2 ns. The first two time-constants are associated with vibrational cooling 27 and charge delocalization on the phen and Per moiety (see Fig. ). Subsequently, the system relaxes back to the ground state with τ3 = 2.9 ns, which agrees with the emission lifetime of phenPer in acetonitrile (τem = 2.9 ns, see Fig. ). The decrease of the excited state lifetime compared to Per (circa 4 ns 28 ) can be rationalized by the presence of additional deactivation-channels in phenPer (e.g. rotation around the bond between the phen and Per unit).