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MO: Fachverband Molekülphysik

MO 12: Photochemistry I

MO 12.4: Vortrag

Mittwoch, 10. März 2010, 11:30–11:45, F 142

Increasing the efficiency of the ring-opening reaction of photochromic indolylfulgides by optical pre-excitation — •Thomas Brust, Simone Draxler, Jonas Eicher, Markus Braun, and Wolfgang Zinth — Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München

Fulgides are interesting candidates for applications as molecular memories or switches [1]. Their reaction dynamics are on the same timescale as cooling dynamics, so the reaction starts from a thermal non-equilibrium [2]. Therfore multipulse experiments can give more insight into the properties of these molecules [3].

In this contribution the quantum efficiency of the ring-opening reaction upon pre-excitation is investigated in a multipulse experiment [4] for three indolylfulgides. The quantum efficiency grows by factor of up to 3.4, when the pre-excitation pulse immediately precedes the excitation process. The change in quantum efficiency after pre-excitation is discussed as a function of reaction time, steady-state quantum efficiency and energetic barriers in the excited electronic state. The observed differences can be explained by the molecular properties of the investigated indolylfulgides [5].

[1] S. Malkmus et al., Adv. Funct. Mater. (2007) 17, 3657

[2] T. Brust et al., J. Photochem. Photobiol. A (2009) 207, 209

[3] S. Draxler et al., Phys. Chem. Chem. Phys. (2009) 11, 5019

[4] S. Draxler et al., Opt. Commun. (2009), doi:10.1016/j.optcom.

2009.10.105

[5] T. Brust et al., Chem. Phys. Lett. (2009) 477, 298