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Rotational alignment effects in NO(X) + Ar inelastic collisions: an experimental study
M Brouard1, H Chadwick, C J Eyles
1The Department of Chemistry, University of Oxford, The Physical and Theoretical Chemistry Laboratory, South Parks Road, Oxford OX1 3QZ, United Kingdom. mark.brouard@chem.ox.ac.uk
The Journal of Chemical Physics
|March 22, 2013
Summary
Collision energy of 66 meV was used to study rotational alignment effects in nitric oxide (NO) and argon (Ar) collisions. The hard shell nature of the interaction potential primarily drives the observed rotational alignment.
Area of Science:
- Chemical Physics
- Molecular Collisions
- Quantum Mechanics
Background:
- Understanding molecular collisions is crucial for chemical reactions and energy transfer.
- Rotational angular momentum alignment influences collision dynamics and outcomes.
- Previous studies lacked detailed, state-resolved experimental data for NO-Ar collisions.
Purpose of the Study:
- To experimentally investigate rotational angular momentum alignment effects in NO(X) colliding with Ar.
- To determine state-resolved differential cross sections for spin-orbit conserving and changing transitions.
- To compare experimental findings with theoretical calculations, particularly exact quantum mechanical scattering.
Main Methods:
- Utilized hexapole electric field for initial state selection of NO(X).
- Employed velocity-map ion imaging for final state detection.
- Measured second-rank renormalized polarization-dependent differential cross sections at 66 meV collision energy.
Main Results:
- Reported fully quantum state-resolved cross sections for selected transitions for the first time.
- Observed good agreement between experimental results and exact quantum mechanical scattering calculations.
- Identified the hard shell nature of the interaction potential as the main cause of rotational alignment.
Conclusions:
- The experimental and theoretical results confirm the significant role of rotational alignment in NO-Ar collisions.
- The hard shell interaction potential model accurately describes the observed alignment effects.
- This study provides valuable benchmark data for theoretical investigations of molecular collisions.
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