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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Photochemistry with Plane-Polarized Light: Controlling Photochemical Reactivity via Spatially Selective Excitation
Maksim V Anokhin1, Evgueni E Nesterov1
1Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115, United States.
The Journal of Physical Chemistry Letters
|September 24, 2020
Summary
Researchers developed a new method to control photochemical reactions using polarized light and liquid crystals. This technique allows for precise spatial excitation of electronic transitions, enhancing reaction selectivity.
Area of Science:
- Photochemistry
- Physical Chemistry
- Materials Science
Background:
- Photochemical reactions are challenging to control due to high-energy excited states.
- Precise control over photochemical processes is crucial for selective synthesis and mechanistic studies.
Purpose of the Study:
- To introduce a novel method for controlling photochemical reactions through spatially selective excitation.
- To demonstrate the efficacy of this method using cyclopropenone photodecarbonylation.
Main Methods:
- Utilizing plane-polarized light irradiation on a photoreactive compound aligned in a nematic liquid-crystalline (LC) medium.
- Spatially selective excitation of specific electronic transitions by controlling the angle between light polarization and LC director.
Main Results:
- Demonstrated control over cyclopropenone photodecarbonylation by adjusting the polarization angle.
- Identified two specific, partially forbidden electronic transitions as key to the observed photochemical reaction.
Conclusions:
- The developed method offers a simple and general approach to control photochemical reactions.
- This technique can enhance selectivity in photochemical transformations and aid in studying fundamental photochemical processes.
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