Time-resolved vibronic spectra with nuclear-electronic orbital time-dependent configuration interaction
Scott M Garner1, Shiv Upadhyay2, Xiaosong Li2
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
The Journal of Chemical Physics
|January 29, 2025
Summary
This study introduces a new ab initio method for simulating photochemical dynamics and vibronic spectra. The nuclear-electronic orbital time-dependent configuration interaction (NEO-TDCI) approach enables accurate quantum simulations of energy transfer and spectroscopic experiments.
Area of Science:
- Quantum chemistry
- Spectroscopy
- Photochemistry
Background:
- Time-resolved spectroscopy is crucial for understanding photochemistry.
- Simulating complex quantum dynamics requires advanced computational methods.
Purpose of the Study:
- To develop a novel ab initio method for simulating vibronic spectra and photochemical dynamics.
- To enable accurate predictions of time-resolved spectroscopic experiments.
Main Methods:
- Utilizing the nuclear-electronic orbital time-dependent configuration interaction (NEO-TDCI) approach.
- Treating electrons and specified nuclei quantum mechanically.
- Calculating time-resolved vibrational and electronic absorption spectra from arbitrary initial conditions.
Main Results:
- Demonstrated the calculation of vibrationally hot spectra by including quantized nuclei.
- Captured ground-state absorption, stimulated emission, and excited-state absorption between vibronic states.
- Successfully simulated time-resolved spectra from vibrational or electronic Rabi oscillations.
Conclusions:
- The developed methodology provides a foundation for fully ab initio simulations of multidimensional spectroscopic experiments.
- This approach enhances the accuracy of theoretical predictions in photochemistry and spectroscopy.
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