Abstract
The steady-state and time-resolved fluorescence spectra were measured for protic solutions of 1- and 2-acetyl- or 1- and 2-benzoylanthracenes at various temperatures. It has been demonstrated that the perturbation of protic solvents on the fluorescence spectra is caused by a combination of the orientational dipolar solvent-solute relaxation and the hydrogen bond interaction. Based on the time-dependent spectral shift and the temperature dependence of fluorescence polarization observed for 2-acylanthracene, the relaxation process of the excited solute has been supposed to involve the level inversion of dual fluorescent states, which respond differently to the solvation of the system.