Fig. 3. (a) Non-radiative decay rate constant of 2vs. solvent H-bonding ability. (b and c) Solvatochromism of 1 and 2. Absorption (b) and emission (c) maximum wavelengths vs. the solvent polarity function.25 (d) Solvatochromism of absorption of 1 and 2 in protic solvents. The points represent individual measurements, and the associated errors of the slopes represent the 95% confidence interval of the fits (see ESI†). TFE = trifluoroethanol; HFP = hexafluoroisopropanol.
