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Updated: Aug 14, 2026
12:11
Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Chemical Interpretation of Time-Dependent Coupled-Cluster Theory
Aparna Krishnan1, Håkon Emil Kristiansen2, Benjamin G Peyton3
1Department of Chemistry, Virginia Tech, Blacksburg, Virginia24061, United States.
The Journal of Physical Chemistry. A
|August 13, 2026
Summary
We developed a method to interpret complex laser-induced electron dynamics simulated by time-dependent coupled-cluster theory. This approach assigns spectral features to specific orbital transitions, aiding chemical understanding.
Area of Science:
- Quantum Chemistry
- Theoretical Chemistry
- Computational Spectroscopy
Background:
- Time-dependent coupled-cluster (TDCC) theory accurately simulates laser-matter interactions.
- TDCC lacks straightforward chemical interpretation of excited states.
- Conventional methods offer simpler spectral assignments.
Purpose of the Study:
- To develop a method for interpreting TDCC simulations of electron dynamics.
- To assign spectral features to orbital transitions.
- To bridge the gap between TDCC accuracy and chemical interpretability.
Main Methods:
- Expanding TDCC functions in a Slater-determinant basis.
- Generalizing configuration weights for population tracking.
- Decomposing dipole moments and autocorrelation functions.
Main Results:
- Developed time-dependent configuration weights for spectral assignment.
- Successfully assigned valence and core-level excitations in small molecules (HF, H2O, NH3, CH4).
- Validated assignments against equation-of-motion coupled-cluster theory.
Conclusions:
- The proposed method provides straightforward spectral assignments for TDCC simulations.
- Enables detailed analysis of laser-induced dynamics and spectra.
- Applicable to various systems, including atoms and molecules, and different spectroscopies.
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