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Updated: Mar 19, 2026
08:51
Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
11.0K
Absolute Configuration from Different Multifragmentation Pathways in Light-Induced Coulomb Explosion Imaging
Martin Pitzer1, Gregor Kastirke1, Maksim Kunitski1
1Institute for Nuclear Physics, Johann-Wolfgang-Goethe-Universität Frankfurt, Max-von-Laue-Straße 1, 60438, Frankfurt, Germany.
Summary
Determining molecular absolute configuration is now more efficient using X-ray photon-induced Coulomb explosion imaging (CEI). This method allows analysis even with incomplete molecular fragmentation, expanding its applicability for chiral molecule stereochemical analysis.
Area of Science:
- * Molecular science and physical chemistry.
- * Chirality and stereochemistry.
- * Advanced imaging techniques.
Background:
- * Determining the absolute configuration of small molecules is crucial in chemistry and biology.
- * Light-induced Coulomb explosion imaging (CEI) has emerged as a direct method for this analysis.
- * Previous CEI methods utilized femtosecond lasers, facing limitations in efficiency and fragmentation completeness.
Purpose of the Study:
- * To demonstrate the application of single X-ray photon ionization in CEI for determining molecular absolute configuration.
- * To enhance the efficiency and speed of the CEI process.
- * To expand the applicability of CEI to molecules with incomplete fragmentation pathways.
Main Methods:
- * Employing single X-ray photons from a synchrotron light source for molecular ionization.
- * Utilizing light-induced Coulomb explosion imaging (CEI) to analyze molecular fragmentation patterns.
- * Investigating incomplete fragmentation pathways of racemic CHBrClF molecules.
Main Results:
- * Achieved enhanced efficiency and faster molecular fragmentation compared to laser-based CEI.
- * Demonstrated that incomplete fragmentation pathways provide access to absolute configuration.
- * Showcased the method's effectiveness on a racemic CHBrClF sample.
Conclusions:
- * Single X-ray photon ionization significantly improves CEI efficiency and speed.
- * CEI can determine absolute configuration even with incomplete molecular fragmentation.
- * This advancement broadens the scope of CEI for routine stereochemical analysis of larger chiral molecules.
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