Figure 1.

A schematic representation of the energetics of electronic transitions in a dye in a polarizable medium (Left) and the corresponding absorption and emission spectra for proflavine dye in a polar medium (Right). The x axis on the left is a generalized classical coordinate describing, e.g., the orientation of surrounding dipoles in the medium. The light absorption (hν_a) and emission (hν_e) transitions are shown at the most probable coordinates that are expected to determine the maxima of the corresponding spectra.