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Updated: Feb 18, 2026

Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
Probing Instantaneous Single-Molecule Chirality in the Planar Ground State of Formic Acid
D Tsitsonis1, M Kircher1, N M Novikovskiy2
1Goethe-Universität Frankfurt, Institut für Kernphysik, Max-von-Laue-Straße 1, 60438 Frankfurt am Main, Germany.
Abstract:
We experimentally demonstrate that individual molecules of formic acid are chiral even when they are in the vibronic ground state, which has a planar equilibrium structure. We ionize the C 1s shell of the molecule and record the photoelectron in coincidence with positively charged fragments. This provides two consecutive measurements of the structure of one molecule, the first by photoelectron diffraction imaging and the second by Coulomb explosion imaging. We find that both measurements show the same handedness of the specific molecule. The phenomenon of being achiral on average but chiral at the level of individual molecules is general to prochiral molecules and is a consequence of the three-dimensional zero-point delocalization of the nuclei in the vibrational ground state.
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