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Q: Quantenoptik
Q 36: Femtosekunden: Analyse und Spektroskopie (gemeinsam mit MO)
Q 36.3: Vortrag
Donnerstag, 27. März 2003, 11:30–11:45, B302
Insights into trans-cis reaction dynamics by fs time-resolved mid-IR spectroscopy — •Frank Peters, Johannes Herbst, and Rolf Diller — Inst. f. Exp. Physik, FU Berlin, 14195 Berlin
In comparison to transient electronic spectroscopy the method of transient vibrational spectroscopy is more suitable to provide insight into processes associated with protein-based photoreactions, as structural changes of the chromophore, its vibrational relaxation and the dynamics of the protein environment. This was demonstrated in [1], where the ultrafast photoinduced isomerization reaction in the light-driven proton pump bacteriorhodopsin (bR) was investigated by time-resolved infrared absorption spectroscopy. It could be shown, that the all-trans to 13-cis isomerization of the retinal chromophore in bR is already completed within 500 fs.
We have now studied model-compounds and other retinal-proteins in order to disentangle important processes that are superimposed temporally and spectrally. Emphasis is placed on the vibrational dynamics in the excited electronic state and the electronic ground state (S0). On the S0-surface, vibrationally excited states are expected to become populated and thus observable in the transient IR-spectra.
[1] Johannes Herbst, Karsten Heyne, Rolf Diller, Science 297(2002) 822.