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Updated: Jul 23, 2026
10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Field induced ion-pair formation from ICl studied by optical triple resonance
Faraday Discussions
|October 21, 2000
Summary
Researchers explored ion-pair states in ICl molecules using multiphoton excitation. High vibrational levels were detected, showing survival for microseconds, indicating molecular stabilization near dissociation.
Area of Science:
- Chemical Physics
- Molecular Spectroscopy
- Quantum Chemistry
Background:
- Understanding molecular dissociation pathways is crucial for chemical dynamics.
- Ion-pair states represent a key intermediate in dissociative processes.
Purpose of the Study:
- To investigate multiphoton excitation pathways to ion-pair states in ICl.
- To characterize the stability and properties of highly vibrationally excited states near the dissociation limit.
Main Methods:
- Utilized multiphoton excitation to access high vibrational levels in ICl.
- Employed pulsed field ionization (PFI) to detect I+ and Cl- ion fragments.
- Varied time delays in PFI to probe the lifetime of excited states.
Main Results:
- Observed ion-pair states up to 50 cm-1 below the dissociation limit surviving for over 2 microseconds.
- Detected a structured atomic ion production signal, indicating the influence of doorway states.
- Demonstrated efficient coupling between doorway states and the ion-pair manifold, competing with decay processes.
Conclusions:
- Identified a stabilization mechanism for highly vibrationally excited ion-pair states in ICl.
- Highlighted the significant role of doorway states in accessing the ion-pair manifold near dissociation.
- Provided insights into the dynamics of molecular dissociation and energy transfer processes.
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