Speakers
Description
Photoelectron Circular Dichroism (PECD) is a method of chiral discrimination, which can aid in our fundamental understanding of electron dynamics and holds promise for future analytical techniques of chiral compounds. In PECD, irradiation of a non-racemic sample by circularly polarized light, resulting in the detachment of an electron, leads to a forward-backward asymmetry of the photoelectron angular distribution. This technique has significant advantages over other optical CD methods, such as absorption circular dichroism, as sensitivity to the molecular chirality can manifest within the electric-dipole approximation, bypassing the need for observation of weak interactions with a molecule’s magnetic moment. Additionally, the use of anions for this technique would allow for mass-selectivity and eliminate the need for X-ray based ionization sources, thus leading to a potentially robust analytical tool for chiral discrimination of multicomponent gas-phase samples. PECD as it pertains to neutral chiral species has flourished over the past two decades, evident by the many theoretical and experimental works now available.1 However, a PECD signal in anions has only been observed within the last year.2
By coupling pre-photodetachment mass selection, tunable detachment, and velocity-map imaging-anion photoelectron spectroscopy, we provide an energy-resolved PECD signal for mass-selected anions. Recently, we have demonstrated this successfully in the study of deprotonated 1-indanol anion, where we observed PECD for many detachment channels, and a maximum PECD asymmetry of 11%. Current aims of the project are focused on improving the resolution for spectroscopic PECD measurements. Such improvements will pave a way to an understanding of the short-range interactions effect on the PECD signal, as well as work towards a robust analytical method for the chiral analysis of dilute, but complex, chemical samples.
- Janssen MH, Powis I. Physical Chemistry Chemical Physics. 2014; 16(3):856-71.
- Krüger P, Weitzel KM. Angewandte Chemie International Edition. 2021; 60(33):17861-5.
| Abstract Number (department-wise) | MP 03 |
|---|---|
| Department | MP (Meijer) |
