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Updated: Jul 6, 2026
08:22
Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Interpreting ultrafast molecular fragmentation dynamics with ab initio electronic structure calculations.
Carlos Trallero1, Brett J Pearson, Thomas Weinacht
1Staecie Institute for Molecular Sciences, Ottawa, Ontario K1A 0R6, Canada.
The Journal of Chemical Physics
|April 2, 2008
Summary
Ultrafast laser pulses induce fragmentation in CHBr(2)COCF(3). Dynamic resonances in the molecular cation influence dissociation pathways, as confirmed by advanced electronic structure calculations.
Area of Science:
- Chemical Physics
- Quantum Chemistry
- Molecular Dynamics
Background:
- Understanding molecular fragmentation following laser excitation is crucial for controlling chemical reactions.
- Previous studies observed dissociation dynamics of CHBr(2)COCF(3) after ultrafast laser pulse excitation.
Purpose of the Study:
- To interpret the fragmentation dynamics of CHBr(2)COCF(3) using high-level ab initio electronic structure calculations.
- To elucidate the role of potential energy surfaces and dynamic resonances in the dissociation process.
Main Methods:
- High-level ab initio electronic structure calculations.
- Multireference second order perturbation theory (MR-SPT) methods.
- Calculation of potential energy surfaces for ground and excited cationic states.
Main Results:
- Confirmed the existence of a charge transfer resonance during wave packet evolution on the ground state potential energy surface of the molecular cation.
- Provided a detailed picture of dissociation dynamics, consistent with earlier experimental observations.
- Ionic spectrum comparisons for similar molecules support the influence of dynamic resonances on dissociation.
Conclusions:
- Dynamic resonances within the molecular cation significantly influence fragmentation pathways.
- Ab initio calculations provide valuable insights into complex dissociation dynamics initiated by intense laser fields.
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