Dresden 2011 – wissenschaftliches Programm

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MO: Fachverband Molekülphysik

MO 34: Photochemistry

MO 34.7: Vortrag

Freitag, 18. März 2011, 12:00–12:15, TOE 317

Photochemistry of 3-hydroxyflavone and its water clusters inside superfluid helium nanodroplets — •Tobias Premke and Alkwin Slenczka — Institut für Physikalische und Theoretische Chemie, Universität Regensburg, 93053 Regensburg, Germany

3-hydroxyflavone is a prototype system for excited state intramolecular proton transfer (ESIPT), which was identified by a Stokes shift in the emission of 8000 cm-1 [1]. Besides numerous other studies, the bare molecule and its water cluster have been investigated in helium droplets [2] as well as in the gas phase [3]. New data will be presented on the investigation of ESIPT in helium droplets for the deuterated isomer of the bare molecule and of the water complex. The spectra of the deuterated molecule confirm that the transfer of the proton or deuterium is not influenced by a barrier. Neither complexation with H2O nor with D2O could hinder the ESIP/DT. The spectra of the water complex revealed significant amounts of backprotonation of D2O prior to pick up by the droplet. While the spectra provide evidence for only a single configuration of the water complex an experimental indication for a particular complex configuration is still missing.

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