Enantiosensitive Photoelectron Spectroscopy of Chiral Aqueous Solutions

Emmy Noether Research Group

Life as we know it is crucially dependent on water, and biochemistry occurs nearly exclusively in aqueous environments, either under bulk solvation conditions or at aqueous interfaces. Beyond simply acting as the ubiquitous medium within which important biochemical reactions occur, water also plays a critical active role in determining the functionality of biomolecules such as amino acids, proteins, and DNA via structure stabilization and mediation of intra- and intermolecular interactions. These building blocks of life are predominantly chiral, meaning that they have a defined handedness and are non-superposble with their mirror images. Although generally chemically and physically indistinguishable, the mirror-image enantiomers of chiral molecules interact differently with other chiral entities. As a result, the activity of these enantiomers can differ dramatically under biological (chiral) conditions. Intermolecular interactions between chiral solutes and neighboring water molecules may also induce chirality in the solute’s hydration shell, with profound implications for enantiomer-dependent chemistry in solution. A clearer understanding of molecular chirality in aqueous solution is thus directly relevant for chemical and life sciences.

Our group’s goal is to develop and utilize a novel and powerful technique to study chirality in aqueous solutions of amino acids: enantiosensitive liquid-jet photoelectron spectroscopy (LJ-PES). Standard LJ-PES enables the direct electronic-structure characterization of molecules in solution with site- and chemical-state specificity. Our group will extend this technique by leveraging 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 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.

Open Positions

Our group is just getting started, and we are looking for motivated new members! Please feel free to reach out if you are interested in a bachelor’s/master’s project, a PhD, or a postdoctoral position.