The resulting energies of CT and LE excitations are depicted in Fig. . In general, the effects of polarizable embedding on the LE energies are small, as has been observed before, e.g., for embedded push-pull polymers 15 or small-molecule donor molecules. Therefore, we only show the GW -BSE/MM results for the respective LEs, indicated by the blue (rubrene at 2.01 eV) and orange (C 60 at 1.97 eV) vertical lines as there is no noticeable disorder. For the CT excitations, the GW -BSE calculations in vacuum already reveal significant energetic disorder, originating from the different rubrene-C 60 conformations and the long-range electrostatic interaction between electron and hole. Individual CT excitation energies are marked by the short green vertical lines in Fig. , where we also show a density-of-states obtained by broadening with a Gaussian function of width 0.1 eV. After polarizable embedding in GW -BSE/MM the CT energies (solid green lines) are shifted to lower energies, with energetic stabilization of up to 1 eV. Note that in vacuum, the CT excitation energies result generally higher than both LEs, which would make a conversion process of a LE on rubrene to a CT state energetically unlikely. After embedding, we find that the energetic stabilization brings several high-energy CTs close to the LEs, and some notably very much lower at 1.65 eV (CT 1 )and 1.42 eV (CT 0 ), respectively. The latter compares favorably with the experimentally measured CT energy of 1.46 eV reported in Ref. However, given the disorder in the CT excitation energies, it is unclear if the measurement truly probes simply the lowest-energy CT state, or one that is preferably dynamically populated during the timescale of the conversion process and the experiment.