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Published on: July 27, 2018
Strong molecular alignment dependence of H2 electron impact ionization dynamics
Physical Review Letters
|September 26, 2012
Summary
Investigating electron impact ionization of molecular hydrogen reveals distinct alignment effects. This finding aligns with theoretical predictions, explaining cross-section behavior through electron rescattering.
Area of Science:
- Atomic and Molecular Physics
- Quantum Chemistry
- Electron-Matter Interactions
Background:
- Electron impact ionization is fundamental to understanding molecular dynamics.
- Previous studies lacked detailed molecular alignment dependence.
- Recent theoretical models require experimental validation.
Purpose of the Study:
- To investigate the alignment dependence of low-energy electron impact single ionization of molecular hydrogen.
- To benchmark theoretical predictions using experimental data.
- To elucidate the role of electron rescattering in ionization processes.
Main Methods:
- Experimental measurement of (e,2e) cross sections for molecular hydrogen at 54 eV.
- Varying molecular alignment relative to the electron impact direction.
- Comparison with time-dependent close-coupling (TDCC) theoretical calculations.
Main Results:
- Observed distinct alignment dependence of (e,2e) cross sections in the perpendicular plane.
- Experimental results show good agreement with TDCC calculations.
- Cross-section behavior is explained by rescattering of the ejected electron.
Conclusions:
- The study confirms the importance of molecular alignment in electron impact ionization.
- Electron rescattering in the molecular potential effectively focuses the ejected electron along the molecular axis.
- Provides crucial experimental data for refining theoretical models of molecular ionization.
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