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Diffractive Imaging of Conical Intersections Amplified by Resonant Infrared Fields
Daniel Keefer1, Jérémy R Rouxel2, Flavia Aleotti3
1Departments of Chemistry and Physics & Astronomy, University of California, Irvine, California 92697-2025, United States.
Journal of the American Chemical Society
|August 17, 2021
Summary
Researchers used infrared light to amplify weak signals from conical intersections during photochemical reactions. This technique enhances the detection of these crucial transition states in reactions like azobenzene photoisomerization.
Area of Science:
- Photochemistry
- Chemical Physics
- Spectroscopy
Background:
- Conical intersections are critical in photochemical reactions, mediating rapid electronic state changes.
- Directly observing conical intersections spectroscopically is challenging due to weak signals often masked by other contributions.
Purpose of the Study:
- To develop a method for enhancing the spectroscopic detection of conical intersections.
- To investigate the influence of resonant infrared fields on conical intersection dynamics.
Main Methods:
- Utilizing time-resolved X-ray diffraction to probe molecular dynamics.
- Applying a resonant infrared field during the conical intersection passage in azobenzene photoisomerization.
Main Results:
- The resonant infrared field significantly enhanced coherence signatures associated with conical intersection passage.
- The applied field did not alter the overall product yield of the photoisomerization reaction.
Conclusions:
- Resonant infrared fields can be used to amplify transition-state signals from conical intersections.
- This approach offers a promising route to overcome detection limits for conical intersections in photochemical processes.
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