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Updated: Mar 11, 2026

Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
Identification of absolute geometries of cis and trans molecular isomers by Coulomb Explosion Imaging
Utuq Ablikim1, Cédric Bomme2, Hui Xiong3
1J. R. Macdonald Laboratory, Physics Dept., Kansas State University, Manhattan, KS 66506, USA.
Abstract:
An experimental route to identify and separate geometric isomers by means of coincident Coulomb explosion imaging is presented, allowing isomer-resolved photoionization studies on isomerically mixed samples. We demonstrate the technique on cis/trans 1,2-dibromoethene (C2H2Br2). The momentum correlation between the bromine ions in a three-body fragmentation process induced by bromine 3d inner-shell photoionization is used to identify the cis and trans structures of the isomers. The experimentally determined momentum correlations and the isomer-resolved fragment-ion kinetic energies are matched closely by a classical Coulomb explosion model.
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