Chiral photoelectron spectroscopy using unpolarized light

Abstract

This Letter studies the symmetry properties of general vector correlations resulting from one-photon excitation of chiral molecules. We show that the parity-odd second rank tensor is nonzero for molecules in all chiral point groups Cn, Dn, T, O, and I. This chirality-sensitive tensor is nonzero even for chiral isotopomers excited by linearly polarized or even unpolarized light. We develop an irreducible tensor theory based on Curie's limiting groups. As an example of vector correlations, recoil-frame photoelectron angular distributions (RFPADs) are calculated for methyloxirane and CHFCl35Cl37. The difference in the RFPAD between a chiral molecule and its mirror image reaches ±35% of the maximum value for the RFPAD for unpolarized light and ±55% of the value for linearly polarized light. Chiral sensitivity in vector correlation is a quite general phenomenon arising from one-photon excitation by unpolarized and linearly polarized light, and we expect it to be of great importance in time-resolved spectroscopy of ultrafast chemical reactions. Published by the American Physical Society 2024