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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
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Strong field quantum control of bimolecular reactions
Jyotirmoy Ray1, Tamar Seideman1
1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA.
The Journal of Chemical Physics
|September 15, 2025
Summary
We developed a quantum control strategy for complex bimolecular reactions using laser fields. This method enhances reaction rates by manipulating molecular interactions and potential energy surfaces, offering new control possibilities.
Area of Science:
- Quantum Chemistry
- Chemical Physics
- Reaction Dynamics
Background:
- Bimolecular reactions present significant quantum control challenges due to complex dynamics and thermal averaging.
- Controlling polyatomic bimolecular reactions is difficult because of coupled electronic states, potential wells, and multiple transition states.
Purpose of the Study:
- To present a novel quantum control strategy for polyatomic bimolecular reactions using laser fields.
- To investigate the enhancement and control of reaction rates in complex chemical systems.
Main Methods:
- Utilizing moderately intense, long-pulse laser fields to interact with the molecular polarizability tensor.
- Generating spatially nonuniform Stark shifts on potential energy surfaces to influence reaction pathways.
- Employing quantum mechanical theory and ab initio calculations for potential energy and polarizability tensor analysis.
Main Results:
- Demonstrated that complexities in polyatomic bimolecular reactions can be leveraged for enhancement and control.
- Showcased how potential wells and the polarizability tensor's spatial structure lead to significant, controllable reaction rate enhancement.
- Validated the approach using the CH(X2Π)+N2(XΣg+1)→HCN(XΣ+1)+N(S4) reaction as a model.
Conclusions:
- The proposed quantum control strategy effectively addresses challenges in bimolecular reactions.
- Laser-induced manipulation of Stark shifts offers a pathway to control and enhance reaction rates.
- The findings are generalizable to various polyatomic bimolecular reactions with complex dynamics.
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