Two-dimensional vibrational-electronic spectra with semiclassical mechanics.
Kritanjan Polley1, Roger F Loring1
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, USA.
The Journal of Chemical Physics
|July 9, 2021
Summary
This study extends the optimized mean trajectory (OMT) approximation to compute two-dimensional vibrational-electronic (2DVE) spectra. The semiclassical OMT method accurately approximates quantum dynamics for complex molecular systems.
Area of Science:
- Chemical Physics
- Spectroscopy
- Quantum Dynamics
Background:
- Two-dimensional vibrational-electronic (2DVE) spectroscopy provides insights into molecular excited states.
- Understanding the influence of initial vibrational states on vibronic spectra is crucial.
Purpose of the Study:
- To extend the optimized mean trajectory (OMT) approximation to calculate 2DVE spectra.
- To assess the accuracy of the OMT method for systems with coupled electronic and vibrational dynamics.
Main Methods:
- The optimized mean trajectory (OMT) approximation, a semiclassical method, was employed.
- Classical trajectories were subjected to semiclassical quantization conditions.
- The OMT method was applied to systems with excitonic and vibronic coupling.
Main Results:
- The OMT approximation was successfully extended to compute 2DVE spectra.
- The method demonstrated good agreement with exact quantum dynamics.
- The OMT method accurately models systems with complex chromophore-environment interactions.
Conclusions:
- The OMT approximation is a viable and accurate semiclassical method for calculating 2DVE spectra.
- This approach offers a computationally efficient way to study complex vibronic dynamics.
- The OMT method provides a powerful tool for analyzing molecular excited-state processes.
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