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Time-resolved X-ray and XUV based spectroscopic methods for nonadiabatic processes in photochemistry
Thomas Schnappinger1, Deependra Jadoun1, Mahesh Gudem1
1Department of Physics, Stockholm University, Albanova University Centre, SE-106 91 Stockholm, Sweden. markus.kowalewski@fysik.su.se.
Chemical Communications (Cambridge, England)
|November 1, 2022
Summary
Conical intersections (CIs) are crucial in molecular photochemistry, enabling ultra-fast reactions. Novel extreme ultraviolet and X-ray spectroscopy techniques offer a way to experimentally observe these challenging nonadiabatic dynamics near CIs.
Area of Science:
- Physical Chemistry
- Quantum Chemistry
- Spectroscopy
Background:
- Conical intersections (CIs) are critical in molecular photochemistry, governing ultra-fast radiationless decay pathways.
- Nonadiabatic phenomena near CIs involve complex electron-nuclear dynamics, challenging experimental observation.
- The breakdown of the Born-Oppenheimer approximation at CIs necessitates advanced theoretical and experimental approaches.
Purpose of the Study:
- To provide a theoretical perspective on novel spectroscopic techniques for observing conical intersections.
- To highlight methods capable of resolving ultra-fast dynamics near CIs.
- To discuss the application of extreme ultraviolet and X-ray spectroscopy in studying nonadiabatic processes.
Main Methods:
- Theoretical analysis of nonadiabatic dynamics.
- Exploration of ultra-short laser pulse spectroscopy.
- Focus on extreme ultraviolet (XUV) and X-ray spectroscopic techniques.
Main Results:
- Novel spectroscopic methods, particularly in the XUV and X-ray regions, show promise for observing CI signatures.
- High spectral and temporal resolution of these techniques are key to resolving ultrafast dynamics.
- These methods offer a pathway to experimentally probe the breakdown of the Born-Oppenheimer approximation.
Conclusions:
- Advanced spectroscopic techniques provide unprecedented opportunities to study conical intersections experimentally.
- Understanding nonadiabatic dynamics near CIs is essential for controlling photochemical reactions.
- Future research should focus on implementing and refining these spectroscopic tools for detailed CI investigations.
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