News and events
24 February 2021
Seminar - Photoinduced Symmetry-Breaking Charge Transfer
Presented By Prof. Eric Vauthey (University of Geneva, Switzerland)
- Online (MS Teams)
No registration required.
About this event
A significant number of multichromophoric systems and multipolar conjugated molecules undergo photoinduced charge transfer along one among several energetically equivalent pathways, resulting in a breaking of their symmetry. Understanding and harnessing these processes is crucial for developments and applications in various areas including solar energy conversion and molecular electronics. Several of our efforts towards such a comprehension of the origins and dynamics of these symmetry-breaking phenomena will be presented.
Photoinduced charge separation between two identical sub-units will be illustrated by studies on perylene-based bichromophoric molecules. They reveal the importance of the environment for the direction of the charge separation and of the coupling of the sub-units for the extent of asymmetry in charge distribution.
Excited-state symmetry breaking in quadrupolar and octupolar D-(pi-A)2,3 or A-(pi D)2,3 molecules leads to a dipolar character of their electronic excited state. We will show how this process can be directly visualised using time-resolved spectroscopy. The influence of various parameters, such as solute-solvent interactions and structural disorder, on the symmetry breaking will be discussed.[5,6] Finally, the relevance of this process to the photochemistry of multipolar molecules will be addressed.
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