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Updated: May 15, 2025
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Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light
Published on: September 12, 2014
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Photochemical Au(I)-Au(I) Bond Formation: A Battle between Intersystem Crossing and Internal Conversion.
Diandong Tang1, Can Liao1, Maxwell Taub1
1Department of Chemistry, University of Washington, Seattle, Washington 98195, United States.
The Journal of Physical Chemistry Letters
|April 8, 2025
Summary
Photoinduced bond formation in gold complexes is driven by intersystem crossing and internal conversion. This study reveals the key mechanisms behind ultrafast gold-gold bonding dynamics in solution.
Area of Science:
- Photochemistry
- Inorganic Chemistry
- Computational Chemistry
Background:
- Experimental evidence shows photoinduced Au-Au bond formation in Au(CN)2-.
- The photochemical driving force for this reaction is not well understood.
Purpose of the Study:
- Investigate the ultrafast Au-Au bonding process in the [Au(CN)2]22- dimer.
- Analyze reaction pathways and state transitions in photochemical dynamics.
Main Methods:
- Nonadiabatic dynamics simulations.
- Incorporate intersystem crossing and internal conversion pathways.
- Analyze transitions among singlet and triplet excited states.
Main Results:
- Intersystem crossing is the primary driver in early ultrafast dynamics.
- Internal conversion among triplet states is crucial after stabilization in higher triplet states.
- Computational results elucidate the mechanistic perspective.
Conclusions:
- Mechanistic insight into ultrafast photochemical reactions.
- Understanding the role of spin-orbit coupling and nonadiabatic coupling in modulating reactions.
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