50-fs photoinduced intramolecular charge separation in triphenylmethane lactones

Bizjak, T.; Karpiuk, J.; Lochbrunner, Stefan und Riedle, Eberhard (Dezember 2004): 50-fs photoinduced intramolecular charge separation in triphenylmethane lactones. In: Journal of Physical Chemistry A, Bd. 108, Nr. 49: S. 10763-10769

Abstract

Upon excitation of their structural subunits, phenolphthalein and malachite green lactone undergo ultrafast intramolecular charge separation with formation of a long-lived charge-transfer state (intramolecular ``radical ion pair''). The kinetics of the primary charge separation in these molecules in aprotic solvents has been studied using femtosecond pump-probe spectroscopy. The phenol radical cation is formed by electron transfer within 50 fs after excitation of phenolphthalein to the S-1 state. In malachite green lactone the products of charge separation are observed 150 fs after excitation to the S-2 state. The results demonstrate that electron transfer in these molecules occurs faster than the time scale of inertial solvation dynamics. An intramolecular vibrational mode to promote charge separation is indicated.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 1089-5639
• Sprache: Englisch