Emmy Noether Project: Enantiosensitive Photoelectron Spectroscopy of Chiral Aqueous Solutions

A clear understanding of molecular chirality in aqueous solution is directly relevant for chemical and life sciences. I propose to utilize a novel and powerful technique to explore chirality in aqueous solutions of amino acids: enantiosensitive liquid-jet photoelectron spectroscopy (LJ-PES). Standard LJ-PES enables the direct study of occupied electronic states for volatile solvents and solutions with site- and chemical-state specificity. I will extend this technique by leveraging two recently-identified phenomena that highlight the photoelectron’s capacity to directly access molecular chirality: photoelectron circular dichroism (PECD) and chirality induced spin selectivity (CISS). Briefly, the former effect describes the asymmetry in the angular distribution and the latter in the spin polarization of photoelectrons generated upon photoionization of chiral systems under specific experimental conditions. The use of angle-resolved PES (as required for PECD) to study liquids is uncommon, and its application to aqueous-phase chiral molecules remains at the cutting edge of molecular physics. Spin-resolved PES (the most direct means to characterize CISS) has not yet been applied to liquids in any capacity. However, the joint development of state-of-the-art LJ-PES instrumentation at the Fritz Haber Institute in Berlin (FHI) and the Helmholtz-Zentrum Berlin (HZB) has now brought the application of these techniques to chiral solutions within reach. The goal of this project is to develop and apply enantiosensitive LJ-PES to target key fundamental and technologically relevant aqueous-phase processes including induced chirality in molecular solvation shells, enantiomer-dependent photolysis and reaction kinetics, and chiral intermolecular recognition.