ANALYSIS OF 2-STATE EXCITED-STATE REACTIONS - FLUORESCENCE DECAY OF 2-NAPHTHOL

The fluorescence decay of 2-naphthol has been investigated as a model system for the general case of two-state excited-state reactions. Decay kinetics are presented as a function of emission wavelength and pH. Depending on the pH, the fluorescence emission of 2-naphthol may arise from one state or from two states reversibly or irreversibly approaching the excited-state equilibrium. Several errors and corrections, common to these types of reactions, must be taken into account and are described. The rate constants for the excited-state reaction have also been determined by several methods. The results are in agreement with the mechanism proposed by Weller based on steady-state fluorescence measurements. Decay measurements for the acetate-facilitated proton transfer of 2-naphthol are also presented. © 1979 American Chemical Society.