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Updated: Jun 29, 2026

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Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Azobenzene photoswitches in bulk materials
Marcus Böckmann1, Nikos L Doltsinis, Dominik Marx
1Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 15, 2008
Summary
A new quantum-classical dynamics method simulates complex photoinduced reactions. It reveals how condensed environments affect azobenzene photoswitching dynamics and timescales.
Area of Science:
- Quantum chemistry
- Condensed-matter physics
- Photochemistry
Background:
- Simulating complex chemical reactions in condensed matter is challenging.
- Understanding photoinduced processes requires accurate dynamic simulations.
Purpose of the Study:
- Develop a nonadiabatic two-scale quantum-classical dynamics method.
- Apply this method to study photoinduced reactions in condensed-matter systems.
Main Methods:
- Developed a nonadiabatic two-scale quantum-classical dynamics approach.
- Applied the method to simulate azobenzene photoswitching in bulk.
Main Results:
- Gained insights into excited-state dynamics of cis-trans azobenzene transformation.
- Revealed the influence of condensed phase environment on reaction mechanisms.
- Determined the impact of the environment on relaxation timescales compared to vacuum.
Conclusions:
- The developed method is suitable for simulating complex photoinduced processes.
- Condensed environments significantly influence photochemical reaction dynamics and timescales.
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Both these photosystems work in concert. An excited electron from PSII is relayed to PSI via an electron transport chain in the thylakoid membrane of the chloroplast, which is comprised of the carrier molecule plastoquinone, the dual-protein cytochrome complex, and plastocyanin. As electrons move between PSII and PSI, they lose energy and must be re-energized...
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