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DOE OSTI · 2419296

Pump-probe spectroscopy of chiral vibrational dynamics

Tikhonov, Denis S.·Blech, Alexander·Leibscher, Monika·Greenman, Loren·Schnell, Melanie·Koch, Christiane P.
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Abstract

A planar molecule may become chiral upon excitation of an out-of-plane vibration, changing its handedness during half a vibrational period. When exciting such a vibration in an ensemble of randomly oriented molecules with an infrared laser, half of the molecules will undergo the vibration phase-shifted by π compared to the other half, and no net chiral signal is observed. This symmetry can be broken by exciting the vibrational motion with a Raman transition in the presence of a static electric field. Subsequent ionization of the vibrating molecules by an extreme ultraviolet pulse probes the time-dependent net handedness via the photoelectron circular dichroism. Our proposal for pump-probe spectroscopy of molecular chirality, based on quantum-chemical theory and discussed for the example of the carbonyl chlorofluoride molecule, is feasible with current experimental technology.

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Tikhonov, Denis S., Blech, Alexander, Leibscher, Monika, Greenman, Loren, Schnell, Melanie, Koch, Christiane P.. 2022-12-07. Pump-probe spectroscopy of chiral vibrational dynamics. https://doi.org/10.1126/sciadv.ade0311

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