Identifiability of competitive intermolecular three-state excited-state processes

The conditions necessary for the recovery of the rateconstants from flourescence decay traces due to competitive intermolecular three-state excited-state processes are investigated. The studied system models a situation where an excited-state species can react competitively with both co-reactants X and Y. It is demonstrated theoretically that, if fluorescence decay traces at two concentrations of X and two concentrations of Y are available, all seven rate constants can always be recovered. In contrast to previously studied intermolecular two-state and three-state excited-state processes, it is not required to obtain a fluorescence decay at [X] = [Y] = 0 Mto assign unique numerical values to all rate constants.