Figure reports percentage of CT character for these three states, as quantified using the RAS-SF CT method, as a function of solvent polarity. We consider the values ε 0 = 1 (corresponding to vacuum boundary conditions), ε 0 = 3 (characteristic of typical thin films such as poly(methyl methacrylate), PMMA), and ε 0 = 37.5 (representing acetonitrile). For model 1 of the dimer, the CT character varies only slightly as a function of these very significant changes in ε 0 , but for model 2 we observe significant changes in CT character in polar versus nonpolar environments. In particular, the S 1 state of model 2 exceeds 50% CT character in acetonitrile as compared to 30% CT character in the gas phase.