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Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
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Deconstructing field-induced ketene isomerization through Lagrangian descriptors.
Galen T Craven1, Rigoberto Hernandez1
1Center for Computational Molecular Science and Technology, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, USA. gtcraven@gatech.edu hernandez@gatech.edu.
Physical Chemistry Chemical Physics : PCCP
|January 19, 2016
Summary
Researchers mapped molecular state transitions in ketene isomerization using Lagrangian descriptors. This work validates a new theory for controlling molecular reactions with external electric fields.
Area of Science:
- Physical Chemistry
- Chemical Dynamics
- Computational Chemistry
Background:
- Molecular isomerization reactions are fundamental to chemical transformations.
- Controlling these reactions with external fields is a key goal in chemistry.
- Understanding the dynamics of field-induced reactions requires advanced theoretical tools.
Purpose of the Study:
- To construct time-dependent geometrical separatrices for field-induced ketene isomerization.
- To model the dynamics of ketene isomerization under oscillating electric fields.
- To validate and extend a transition state theory framework using Lagrangian descriptors.
Main Methods:
- Utilizing Lagrangian descriptors to identify time-dependent separatrices.
- Performing classical trajectory studies on a potential energy surface.
- Coupling an approximate dipole moment model to a time-dependent electric field.
Main Results:
- Obtained stable and unstable manifolds of time-varying transition states.
- Partitioned initial phase space into product state basins.
- Demonstrated agreement between basin borders and Lagrangian descriptors, even in chaotic regimes.
Conclusions:
- Validated and extended a transition state theory framework based on Lagrangian descriptors.
- Elaborated on the applicability of this theory to driven molecular systems.
- Predicted conditions for controlling ketene isomerization with external fields.
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