Photochemistry of 'super'-photoacids. Solvent effects

Super-photoacids, such as 5-cyano-2-naphthol, tend to undergo excited-sate proton transfer within their chromophore, when subjected to a series of time-resolved fluorescence. An empirical analysis involving the Kamlet-Taft approach indicate that majority of the shifting phenomenon in the excitation spectra is made possible through the action of hydrogen bonds, which have been donated from the OH group. The hydrogen bond contained by super-photoacids has also been shown to gather intensity during the excited state.