Influence of Vibrational Excitation and Nuclear Dynamics in Multiphoton Photoelectron Circular Dichroism of Fenchone

Singh, Dhirendra P.; Thompson, James O. F.; Reid, Katharine L.; Powis, Ivan

Abstract

We report photoelectron circular dichroism of S-(+)-fenchone enantiomers recorded with state-state vibrational level resolution using picosecond laser (2 + 1) resonance enhanced multiphoton ionization via 3s and 3p Rydberg intermediate states. The 3p state decays to the 3s state on a picosecond time scale so that, above the 3p Rydberg excitation threshold, ionization of vibrationally hot 3s states competes with direct 3p-1 ionization. Complex vibronic dynamics of the 3p → 3s internal conversion weaken the Rydberg Δv = 0 propensity rule in both the 3p-1 and 3s-1 ionization channels. Large variations of the forward-backward chiral asymmetry factors are observed between the Δv = 0 and Δv > 0 vibrational transitions, including dramatic swings from up to ±17%. Such changes of sign indicate complete reversal of the preferred direction for photoelectron emission in the laboratory frame, associated with vibrational motion. These asymmetry switches easily exceed the amplitude and frequency of such vibrationally induced flips previously observed in single photon ionization.

Citation

Singh, D. P., Thompson, J. O. F., Reid, K. L., & Powis, I. (2021). Influence of Vibrational Excitation and Nuclear Dynamics in Multiphoton Photoelectron Circular Dichroism of Fenchone. Journal of Physical Chemistry Letters, 12(46), 11438-11443. https://doi.org/10.1021/acs.jpclett.1c03231

• Journal Article Type: Article
• Acceptance Date: Nov 9, 2021
• Online Publication Date: Nov 18, 2021
• Publication Date: Nov 25, 2021
• Deposit Date: Nov 25, 2021
• Publicly Available Date: Nov 19, 2022
• Journal: Journal of Physical Chemistry Letters
• Electronic ISSN: 1948-7185
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 12
• Issue: 46
• Pages: 11438-11443
• DOI: https://doi.org/10.1021/acs.jpclett.1c03231
• Keywords: General Materials Science; Physical and Theoretical Chemistry
• Public URL: https://nottingham-repository.worktribe.com/output/6788395
• Publisher URL: https://pubs.acs.org/doi/10.1021/acs.jpclett.1c03231
• Additional Information: This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of Physical Chemistry Letters. copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acs.jpclett.1c03231.