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Updated: Jun 23, 2026
08:51
Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
Neural network based molecular structure retrieval from Coulomb explosion imaging data
A Ghanaatian1, A K Ravi2, J Stallbaumer3
1Department of Computer Science, Kansas State University, Manhattan, Kansas 66506, USA.
The Journal of Chemical Physics
|June 22, 2026
Summary
We developed a new AI method using neural networks to reconstruct molecular structures from Coulomb explosion imaging data. This technique enables precise, event-by-event analysis of molecular dynamics in ultrafast chemistry.
Area of Science:
- Ultrafast molecular physics and chemistry
- Atomic and molecular physics
- Computational chemistry
Background:
- Determining molecular structure and evolution during reactions is crucial in ultrafast science.
- Coulomb explosion imaging (CEI) shows promise for real-time molecular structure analysis.
- Current CEI methods lack direct algorithms for retrieving molecular structure from fragment-ion data.
Purpose of the Study:
- To develop a novel algorithm for direct molecular structure retrieval from CEI data.
- To address the inverse problem of inferring molecular geometry from fragment-ion momenta.
- To enable automated, event-by-event structure determination in CEI experiments.
Main Methods:
- Utilized neural networks to solve the inverse problem in CEI.
- Trained networks to infer initial atomic positions from final fragment-ion momenta.
- Applied the scheme to simulated CEI data of polyhalomethane isomers.
Main Results:
- Successfully retrieved molecular structures from simulated CEI data.
- Achieved an average per-atom position error of approximately 0.1 atomic units.
- Demonstrated accuracy within 5% of typical bond lengths for retrieved structures.
Conclusions:
- The proposed neural network scheme enables automated, direct structure retrieval from CEI data.
- This method allows for single-molecule analysis, crucial for complex reaction dynamics.
- Facilitates the analysis of pump-probe experiments with multiple reaction products.
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