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Laser-induced dynamics of molecules with strong nuclear quadrupole coupling
Andrey Yachmenev1, Linda V Thesing1, Jochen Küpper1
1Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany.
The Journal of Chemical Physics
|January 3, 2020
Summary
We developed a new computational method to simulate molecular laser dynamics, including nuclear quadrupole coupling. This method reveals that hyperfine effects initially have minor impacts but become detrimental to molecular alignment over time.
Area of Science:
- Quantum chemistry
- Molecular dynamics
- Spectroscopy
Background:
- Accurate computation of molecular dynamics is crucial for understanding laser-molecule interactions.
- Nuclear quadrupole coupling significantly influences molecular energy levels and dynamics.
Purpose of the Study:
- To present a general variational approach for computing laser-induced rovibrational dynamics, incorporating nuclear quadrupole coupling.
- To investigate the impact of nuclear quadrupole coupling on short-pulse laser alignment of CFClBrI.
Main Methods:
- Combined the TROVE (Theoretical Ro-Vibrational Energies) and RichMol variational methods.
- Simulated rovibrational dynamics of CFClBrI under laser-induced alignment, considering hyperfine effects.
Main Results:
- Nuclear quadrupole coupling has a negligible effect on early-time molecular dynamics and alignment.
- At longer timescales, nuclear quadrupole interactions detrimentally affect molecular alignment, with intensity dependence.
- Dephasing of the rotational wavepacket due to hyperfine splitting explains the observed detrimental effects.
Conclusions:
- The developed variational approach accurately captures laser-induced molecular dynamics with hyperfine effects.
- Nuclear quadrupole coupling plays a significant role in long-term molecular alignment dynamics.
- Understanding these effects is critical for controlling molecular behavior with lasers.
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