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Published on: December 4, 2017
Chemical reaction dynamics beyond the Born-Oppenheimer approximation
1Department of Chemistry and The James Franck Institute, The University of Chicago, Chicago, Illinois 60637, USA. ljb4@midway.uchicago.edu
Annual Review of Physical Chemistry
|March 12, 2004
Summary
Chemists can predict chemical reaction pathways by examining how the Born-Oppenheimer approximation breaks down. This breakdown influences molecular dissociation dynamics and branching between reaction pathways.
Area of Science:
- Chemical Dynamics
- Quantum Chemistry
- Spectroscopy
Background:
- Predicting chemical reaction branching typically relies on single adiabatic potential energy surfaces.
- The Born-Oppenheimer approximation assumes electronic wavefunctions evolve rapidly compared to nuclear motion.
Purpose of the Study:
- Investigate how the breakdown of the Born-Oppenheimer approximation affects molecular dissociation pathways.
- Explore the influence of nonadiabatic behavior on branching between energetically allowed reaction pathways.
Main Methods:
- Experimental studies reviewed focus on nonadiabatic dynamics.
- Analysis of intramolecular distance and orbital orientation effects on nonadiabaticity.
- Investigating the role of nuclear dynamics in mediating nonadiabatic coupling.
Main Results:
- Identified chemical reaction classes exhibiting significant nonadiabatic behavior.
- Demonstrated the impact of electronic orbital interactions on reaction pathway branching.
- Showcased how nuclear motion influences effective nonadiabatic coupling.
Conclusions:
- Nonadiabatic effects, driven by the breakdown of the Born-Oppenheimer approximation, significantly alter chemical reaction dynamics.
- Understanding these nonadiabatic dynamics is crucial for accurately predicting molecular dissociation pathways and reaction branching.
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