# Emitter-site selective photoelectron circular dichroism of trifluoromethyloxirane

## TL;DR

This study investigates the site-specific photoelectron circular dichroism in trifluoromethyloxirane, revealing strong emitter- and site-sensitivity in inner-shell ionization with experimental and theoretical agreement.

## Contribution

It provides the first detailed experimental and theoretical analysis of site-specific PECD in a chiral molecule's inner-shell ionization.

## Key findings

- Observed up to 9% PECD asymmetry for oxygen K-shell ionization.
- Predicted similar asymmetries for fluorine atoms, averaging around 2%.
- Confirmed strong emitter- and site-sensitivity of PECD in the molecule.

## Abstract

The angle-resolved inner-shell photoionization of R-trifluoromethyloxirane, C3H3F3O, is studied experimentally and theoretically. Thereby, we investigate the photoelectron circular dichroism (PECD) for nearly-symmetric O 1s and F 1s electronic orbitals, which are localized on different molecular sites. The respective dichroic $\beta_{1}$ and angular distribution $\beta_{2}$ parameters are measured at the photoelectron kinetic energies from 1 to 16 eV by using variably polarized synchrotron radiation and velocity map imaging spectroscopy. The present experimental results are in good agreement with the outcome of ab initio electronic structure calculations. We report a sizable chiral asymmetry $\beta_{1}$ of up to about 9% for the K-shell photoionization of oxygen atom. For the individual fluorine atoms, the present calculations predict asymmetries of similar size. However, being averaged over all fluorine atoms, it drops down to about 2%, as also observed in the present experiment. Our study demonstrates a strong emitter- and site-sensitivity of PECD in the one-photon inner-shell ionization of this chiral molecule.