Femtosecond Studies of Vibrationally Hot Molecules Produced by Intramolecular Proton-Transfer in the Excited-State

Chudoba, C.; Lutgen, S.; Jentzsch, T.; Riedle, Eberhard ; Woerner, M. und Elsaesser, T. (Juni 1995): Femtosecond Studies of Vibrationally Hot Molecules Produced by Intramolecular Proton-Transfer in the Excited-State. In: Chemical Physics Letters, Bd. 240, Nr. 1-3: S. 35-41

Abstract

The keto-type reaction product of intramolecular proton transfer in the excited state of 2-(2'-hydroxy-5'methylphenyl)benzotriazole is investigated by femtosecond experiments in a wide spectral range. Keto-type molecules produced on a 100 fs time scale show an emission band between 600 and 800 nm that decays with a time constant of 150 fs. The strong spectral overlap of the emission with the absorption spectrum of the keto-type ground state extending from 400 to 700 nm gives evidence of non-equilibrium vibrational excitations of the product molecules. The keto-type species decays by proton back-transfer to the enol ground state with a time constant of 600 fs. Measurements with different excitation wavelengths demonstrate that the rates of this ultrafast reaction cycle are not affected by the initial amount of vibronic excess energy.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 0009-2614
• Sprache: Englisch