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Dynamic stark control of photochemical processes.
Benjamin J Sussman1, Dave Townsend, Misha Yu Ivanov
1Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada.
Science (New York, N.Y.)
|October 14, 2006
Summary
Researchers control photochemical reactions using the dynamic Stark effect with precisely timed infrared laser pulses. This method modifies reaction pathways without electronic transitions, showing broad applicability for polarizable molecules.
Area of Science:
- Photochemistry
- Chemical Physics
- Laser Spectroscopy
Background:
- Photochemical reactions are crucial in chemistry and biology.
- Controlling reaction outcomes is a key challenge.
- Existing methods often lack precision or broad applicability.
Purpose of the Study:
- To present a novel method for controlling photochemical reaction outcomes.
- To demonstrate the dynamic Stark control (DSC) of chemical reactions.
- To explore the broad applicability of DSC in molecular reactions.
Main Methods:
- Utilizing the dynamic Stark effect induced by a strong, nonresonant infrared laser field.
- Applying precisely timed infrared laser pulses to modify potential energy barriers.
- Experimentally demonstrating DSC in the nonadiabatic photochemical dissociation of IBr.
Main Results:
- Substantial modification of reaction channel probabilities in IBr dissociation was achieved.
- The DSC process was shown to be nonperturbative and insensitive to laser frequency.
- The method demonstrated reversible modification of potential energy barriers without electronic transitions.
Conclusions:
- Dynamic Stark control offers a precise and versatile method for directing photochemical reactions.
- The DSC technique has broad applicability to all polarizable molecules.
- This approach opens new avenues for controlling chemical transformations at the molecular level.
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