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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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Unveiling Coherent Control of Halomethane Dissociation Induced by a Single Strong Ultraviolet Pulse
Wen-Quan Jing1,2, Zhao-Peng Sun3, Song-Feng Zhao1
1College of Physics and Electronic Engineering, Northwest Normal University, Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, Lanzhou 730070, China.
The Journal of Physical Chemistry Letters
|December 8, 2023
Summary
We theoretically explored controlling halomethane photodissociation using femtosecond laser pulses. Manipulating laser pulse spectral phase suppresses resonance Raman scattering, enabling precise control over molecular dissociation pathways.
Area of Science:
- Chemical Physics
- Quantum Control
- Molecular Dynamics
Background:
- Photodissociation reactions are fundamental in chemistry.
- Controlling molecular reactions with light is a key goal in femtochemistry.
- Halomethanes serve as model systems for studying photodissociation dynamics.
Purpose of the Study:
- To theoretically investigate the coherent control of CH2BrCl photodissociation.
- To examine the influence of laser pulse spectral phase on dissociation pathways.
- To explore the suppression of resonance Raman scattering via quantum interference.
Main Methods:
- Theoretical investigation of photodissociation dynamics.
- Simulation of CH2BrCl photodissociation using femtosecond laser pulses with controlled spectral phase.
- Calculation of excited state population distributions and resonance Raman scattering phenomena.
Main Results:
- Sensitivity of total dissociation probability and radical product yields (Br+CH2Cl, Cl+CH2Br) to chirp rates was revealed.
- Resonance Raman scattering (RRS) was observed in the strong-field regime.
- Chirped pulses were shown to suppress RRS through quantum destructive interference.
Conclusions:
- Coherent control of photodissociation in halomethanes is achievable by manipulating laser pulse spectral phase.
- Quantum destructive interference offers a mechanism to control RRS and influence dissociation outcomes.
- Findings highlight the potential for advanced control in polyatomic molecule photodissociation, advancing femtochemistry.
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