Zvaná přednáška – Eric Vauthey

Photoinduced electron transfer in symmetric molecular systems occurs along one of several equivalent pathways and leads to a breaking of the symmetry. A well-known example is the reaction center of several photosynthetic organisms where charge separation is only taking place along one of the two identical branches.

Two types of photoinduced symmetry-breaking charge-transfer process in more simple systems will be presented. The first concerns charge separation between two identical molecules, and the second charge transfer in molecules containing two or more identical donor-acceptor branches.

I will show how symmetry breaking can be visualised in real time using ultrafast spectroscopy and discuss the main factors governing these processes.

1. Vauthey, E., Photoinduced Symmetry-Breaking Charge Separation. ChemPhysChem 2012, 13, 2001–2011.
2. Aster, A.; Licari, G.; Zinna, F.; Brun, E.; Kumpulainen, T.; Tajkhorshid, E.; Lacour, J.; Vauthey, E., Tuning Symmetry Breaking Charge Separation in Perylene Bichromophores by Conformational Control. Chem. Sci. 2019, 10, 10629–10639.
3. Dereka, B.; Rosspeintner, A.; Li, Z.; Liska, R.; Vauthey, E., Direct Visualization of Excited-State Symmetry Breaking Using Ultrafast Time-Resolved Infrared Spectroscopy. J. Am. Chem. Soc. 2016, 138, 4643–4649.