ChemInform Abstract: Photochemical Primary Processes of Xanthene Dyes. Part 10. The Influence of Ionic Micelles on the Fluorescence Quenching of Xanthene Dyes with Diazonium Ions.

ChemInform Abstract

With a view to obtaining informations about the dye-sensitized photolysis of diazonium salts the steady-state and the time-resolved fluorescence quenching of the title dyes (I) and (II) by the diazonium salts (III) is investigated. The fluorescence of (II) is more efficiently quenched than that of (I) due to the opposite charge of (II) and (III). The quenching of (I) is more effective in the presence of anionic micelles because (I) and (III) are solubilized in the Stern region of the micelles. In the presence of cationic micelles the fluorescence of (II) is only quenched by (IIIb) which is solubilized in the micelles like a tenside ion. The distribution of (III) between the water phase and the micelles is determined and the importance of the singlet state for the dye-sensitized photolysis of (III) is discussed.