Electronic Spectra of Salicylamide in Polycrystalline Form and Solid Environment

The fluorescence emission of crystalline salicylamide (λ$\text{}_{max}$ = 426 nm, Stokes shift 6500 cm$\text{}^{-1}$) is attributed to the proton-transferred species. We suppose that the peak at 359 nm in the substructure of fluorescence excitation spectrum at 77 K is in fact the position of the 0-0 transition. The luminescence and excitation spectra of protolytic forms (anion, neutral molecule and cation) of salicylamide in solid solutions were also examined, as well as the equilibria and photoprocesses in the excited state.