Freiburg 2024 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

MO: Fachverband Molekülphysik

MO 23: Poster: Chirality

MO 23.8: Poster

Thursday, March 14, 2024, 17:00–19:00, Tent C

Towards Comparing the PECD Effect in Closed-Shell and Open-Shell Chiral Molecules — •Viktoria K. Brandt, André Fielicke, Gerard Meijer, and Mallory Green — Department of Molecular Physics, Fritz Haber Institute of the MPG, Berlin

Photoelectron Circular Dichroism (PECD) is a chiral optical effect that manifests in the angle-dependent photoemission of an electron upon irradiation of a chiral molecule by circularly polarized light. A PECD effect in anions was observed for the first time in 2021, showing that forces other than long-range coulombic interactions can yield a measurable PECD effect. To further explore the effect of short-range forces, as well as the universal electron dynamics that govern PECD, 1-phenylethanol was investigated as a closed-shell deprotonated anion, a dehydrogenated, neutral radical and a closed-shell neutral. A photoelectron spectrum of the anion showed the presence of only two deprotonated tautomers. However, the landscape of radical isomers, formed by reaction with fluorine atoms, is calculated to be complicated and includes a large number of achiral species, making a comparison to the closed-shell species difficult. In the energy region that overlaps with predicted spectra of chiral isomers, photoionization of the radical enantiomers shows a reversal of a small PECD effect. However, statistics of this effect are low and confirmation of this effect is still inconclusive. At this point, only the closed-shell neutral has a confirmed PECD measured at around 5%. Further work will focus on obtaining a PECD of the closed-shell anion and identifying new molecular targets with less complicated isomeric landscapes.

Keywords: Photoelectron Circular Dichroism (PECD); Anion Photoelectron Spectroscopy; Radical Photoelectron Spectroscopy; Anion Photoelectron Circular Dichroism (PECD); Radical Photoelectron Circular Dichroism (PECD)