Coulomb Explosion Imaging of Complex Molecules Using Highly Charged Ions.

Area of Science:

• Atomic and Molecular Physics
• Chemical Physics
• Materials Science

Background:

• Coulomb explosion imaging requires rapid multi-electron removal and complete molecular fragmentation.
• Achieving high charge states on target atoms is crucial for accurate structural analysis.

Purpose of the Study:

• To demonstrate the efficacy of highly charged ion beams for Coulomb explosion imaging.
• To distinguish between isomers of C4H4N2 (pyridazine, pyrimidine, pyrazine) using this technique.

Main Methods:

• Utilizing a 112.5 keV/u C5+ highly charged ion beam.
• Inducing Coulomb explosion in pyridazine, pyrimidine, and pyrazine molecules.
• Detecting ionic fragments (H+, C2+, C+, N+) in quadruple coincidence.

Main Results:

• Successfully imaged the structures of pyridazine, pyrimidine, and pyrazine.
• Unambiguously distinguished the three isomers based on fragment angular correlation spectra.
• Visualized molecular structures with high accuracy, confirmed by quantitative agreement with a point-charge model.

Conclusions:

• Highly charged ion beams are powerful tools for Coulomb explosion imaging.
• This approach allows for precise structural determination of complex molecules.
• The fast collision dynamics minimize molecular configuration distortion during imaging.