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Published on: August 18, 2017
Communications: When diffraction rules the stereodynamics of rotationally inelastic collisions
Mikhail Lemeshko1, Pablo G Jambrina, Marcelo P de Miranda
1Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, Berlin D-14195, Germany. mikhail.lemeshko@gmail.com
The Journal of Chemical Physics
|May 6, 2010
Summary
Stereodynamics in atom-molecule collisions are governed by wave diffraction. This study confirms a universal pattern for diffraction-driven stereodynamics across various systems like Helium-Nitric Oxide (He-NO).
Area of Science:
- Physical Chemistry
- Chemical Physics
- Atomic and Molecular Collisions
Background:
- Recent work explored vector correlations in Argon-Nitric Oxide (Ar-NO) collisions.
- Understanding stereodynamics in atom-molecule collisions is crucial for reaction control.
Purpose of the Study:
- To compare model results with close-coupling calculations for Helium-Nitric Oxide (He-NO) collisions.
- To investigate the role of diffraction in determining collision stereodynamics.
- To identify a universal pattern for diffraction-driven stereodynamics.
Main Methods:
- Comparison of theoretical model results with exact close-coupling calculations.
- Analysis of polarization moments for various collision channels and energies.
- Examination of stereodynamics for He-NO, He-O(2), He-OH, and He-CaH systems.
Main Results:
- Striking agreement between the model and exact polarization moments for He-NO collisions.
- Confirmation that stereodynamics are governed by matter wave diffraction from a repulsive core.
- Identification of a single, distinctive pattern in model polarization moments across different systems.
Conclusions:
- Diffraction of matter waves is the primary mechanism governing stereodynamics in rotationally inelastic atom-molecule collisions at thermal energies.
- The identified pattern serves as a universal 'fingerprint' for diffraction-driven stereodynamics.
- This finding has implications for predicting and controlling stereochemical outcomes in chemical reactions.
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