For all electronic structure calculations, we use the CAM-B3LYP/6-31G(d) level of theory with empirical dispersion accounted via the D3 version of Grimmes dispersion. Because the TDA usually provides excitation energy and vibronic lineshapes similar to TDDFT and is computationally cheaper than TDDFT 104 , we use the TDA within TDDFT for the excited state properties. Comparisons between TD and TDA are also provided in the Supplementary Material for each dye. The performance of the various density functionals for excited state properties, including fluorescence, has been evaluated previously, with range-separated hybrid functionals found to be superior. Here we focus on the absorption and fluorescence vibronic lineshapes and provide comparisons for FC spectra using CAM-B3LYP 100 , LC-ωHPBE 106-108 , and M06-2x 109 density functionals in both implicit and explicit solvents. These results are detailed in the SM for each dye.