Photochemistry of salicylate anion in aqueous solution

Photochemistry of the salicylate anion (HSA − ) in aqueous solutions was studied by optical spectroscopy, fluorescence spectroscopy, and nanosecond laser flash photolysis (XeCl laser, 308 nm). Excitation of this species gives rise to the HSA − triplet state, HSA · radical, and hydrated electron. The last two species are presumably formed due to the absorption of the second photon by the excited singlet state of the anion. In a neutral medium, the main decay channel of the HSA − triplet state is triplet-triplet (T-T) annihilation. The HSA · radical decays in recombination, and the hydrated electron reacts mainly with the HSA − anion.