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Published on: July 19, 2019
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Photoisomerization-coupled electron transfer
Jakub K Sowa1, Emily A Weiss1, Tamar Seideman1
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA.
The Journal of Chemical Physics
|July 28, 2020
Summary
Researchers explored a new ultrafast electron transfer triggered by photochromic molecular photoisomerization. This study reveals that electron transfer and photoisomerization are linked, offering new ways to control molecular switches.
Area of Science:
- Molecular Science
- Photochemistry
- Theoretical Chemistry
Background:
- Photochromic molecular structures are key for molecular switches and sensors.
- Their role as light-switchable electron donor/acceptor units is promising.
- A novel process of simultaneous photoisomerization and electron transfer is proposed.
Purpose of the Study:
- To investigate ultrafast electron transfer triggered by simultaneous photoisomerization.
- To develop a theoretical model for this coupled process.
- To apply the model to a dihydropyrene-type photochromic molecular donor.
Main Methods:
- Theoretical modeling of the phenomenon.
- Density functional theory (DFT) calculations.
- Analysis of wavepacket dynamics and photoisomerization yield.
Main Results:
- Electron transfer and photoisomerization are generally inseparable processes.
- The two phenomena must be treated in a unified manner.
- Demonstrated the interplay between photoisomerization and electron transfer in a model system.
Conclusions:
- Photoisomerization-coupled electron transfer is a significant phenomenon in photochromic systems.
- Experimental control over the efficiency of this coupled process is feasible.
- Opens new avenues for designing advanced molecular devices.
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