Photoelectron circular dichroism upon multiphoton ionization of a chiral alcohol

TL;DR

This study reports the first measurements of photoelectron circular dichroism in chiral alcohols using multiphoton ionization, demonstrating a reliable, compact spectrometer setup that advances analytical chiral spectroscopy.

Contribution

First PECD measurements on chiral alcohols using multiphoton ionization with a new compact spectrometer setup.

Findings

PECD values around 2% were observed.

Experimental uncertainties below 0.3% were achieved.

Velocity-map imaging enabled discrimination of spectral features.

Abstract

We present the first photoelectron circular dichroism (PECD) measurements of chiral alcohols, and in particular 1-Phenylethanol, using multiphoton ionization at 400 nm. Observed PECD values were rather small at $\sim2$%, but could be reliably extracted using both hemispherical integration and Abel inversion approaches. Experimental uncertainties of $<0.3$% (2$\sigma$) were achieved with a collection time of around 2 hours. All experiments were conducted in a new compact spectrometer, featuring a continuous flow supersonic expansion and velocity-map imaging detection. The latter is crucial to extract reliable PECD values, as it allows discrimination of different features in the photoelectron spectrum, which exhibit different and opposing PECD signals. The use of a tabletop multiphoton universal ionization scheme is an important step towards a viable analytical chiral spectrometer based on PECD.