Oxygen-specific photoelectron circular dichroism in gas-phase fenchone

Understanding the light-driven responses of chiral molecular systems at a fundamental level—electronically—via photoelectron circular dichroism (PECD) provides a pathway to unlock the intricate mechanisms governing the functionality of chiral molecules. The specific role of oxygen atoms in chiral compounds remains under-explored, despite their pivotal role in numerous functional systems. We report a joint experimental and theoretical study of the PECD of O 1 s electrons from the randomly oriented chiral molecule fenchone ( C 10 H 16 O ) in the gas phase across a kinetic-energy range from 3 to 15 eV. We observe a substantial forward-backward asymmetry in the electron emission patterns across several eV, which is well reproduced by relaxed-core Hartree-Fock calculations. Our results provide a site-specific perspective on the chiral sensitivity of an oxygen atom directly connected to the stereocenter of a chiral molecule.