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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Asymmetric photolysis with elliptically polarized light
1Department of Chemistry, Stanford University, Stanford, CA 94305, USA.
Summary
This study reveals that elliptically polarized light (REPL and LEPL) can induce asymmetric photolysis, similar to circularly polarized light (RCPL and LCPL), though to a lesser extent. This finding broadens our understanding of light-induced chemical reactions.
Area of Science:
- Photochemistry
- Physical Organic Chemistry
- Astrochemistry
Background:
- Right- (RCPL) and left- (LCPL) circularly polarized light are known to induce asymmetric photolysis of racemic organic substrates, yielding enantiomeric excesses (e.e.s).
- Synchrotron radiation, a cosmic source, contains elliptically polarized components (REPL and LEPL) alongside circularly polarized light.
Purpose of the Study:
- To investigate the potential of right- (REPL) and left- (LEPL) elliptically polarized light in inducing asymmetric photolysis.
- To compare the efficacy of REPL and LEPL with RCPL and LCPL in asymmetric photolysis.
Main Methods:
- Utilized a 212.8 nm laser beam to simulate synchrotron radiation.
- Exposed racemic organic substrates to REPL and LEPL.
- Qualitatively assessed the induced asymmetric photolysis and enantiomeric excesses.
Main Results:
- Elliptically polarized light (REPL and LEPL) was found to induce asymmetric photolysis.
- The effect of REPL and LEPL was qualitatively similar to that of RCPL and LCPL.
- The degree of asymmetric photolysis induced by REPL and LEPL was less pronounced than that induced by RCPL and LCPL.
Conclusions:
- Elliptically polarized light possesses the capability to promote asymmetric photolysis.
- This finding expands the scope of light polarization effects in chiral chemistry.
- The study suggests REPL and LEPL may play a role in cosmic asymmetric synthesis.
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