Ground‐State Photoelectron Circular Dichroism of Methyl p‐Tolyl Sulfoxide by Single‐Photon Ionisation from a Table‐Top Source. Issue 24 (19th September 2022)

• Record Type: Journal Article
• Authors: Waters, Max D. J.; Ladda, Nicolas; Senftleben, Arne; Svoboda, Vít; Belozertsev, Mikhail; Baumert, Thomas; Wörner, Hans Jakob
• Is Part Of: Chemphyschem. Volume 23:Issue 24(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-09-19
• Subjects: chirality -- high harmonic generation -- photoelectron circular dichroism -- methyl para-tolyl sulfoxide -- velocity map imaging; Chemistry, Physical and theoretical -- Periodicals; 541.05
• DOI: 10.1002/cphc.202200575
• Languages: English
• ISSNs: 1439-4235

Abstract

Abstract: Single‐photon ionisation of enantiopure methyl p ‐tolyl sulfoxide by circularly polarised light at 133 nm shows remarkably strong photoelectron circular dichroism (PECD), which has been measured in a velocity‐map‐imaging spectrometer. Both enantiomers were measured, each showing a PECD of a similar magnitude (ca. 25 %). These experiments were carried out with a tabletop high‐harmonic source with a photon energy of 9.3 eV, capable of ionising the electronic ground state of most organic and inorganic molecules. Ab‐initio scattering calculations provide a theoretical value of the expected chiral asymmetry parameter, and agree very well with the measured values once orbital mixing via configuration interaction in the cation is taken into account. This study demonstrates a simple photoionisation scheme that can be readily applied to study the time‐resolved PECD of photochemical reactions and suggests a pronounced sensitivity of PECD to electronic configuration interaction in the cation. Abstract : Using circularly‐polarised vacuum ultraviolet light generated from a high‐harmonic source, the remarkably large ground state photoelectron circular dichroism (PECD) of methyl p‐tolyl sulfoxide of 25 % is shown. The observation matches quantitatively with a theory that accounts for configuration interaction. Thus, PECD is sensitive to the electron configuration in a way that traditional photoelectron spectroscopy is not.