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Real-time propagation of adaptive sampling selected configuration interaction wave functions
Avijit Shee1, Zhen Huang2, Martin Head-Gordon1
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
The Journal of Chemical Physics
|March 24, 2025
Summary
A new time-dependent adaptive sampling configuration interaction (TD-ASCI) method accurately simulates strongly correlated molecular dynamics. This method efficiently computes absorption spectra, offering a stable and reliable approach for complex systems.
Area of Science:
- Quantum chemistry
- Computational physics
- Molecular dynamics
Background:
- Strongly correlated systems present significant challenges in accurately describing their quantum dynamics.
- Existing methods often struggle with stability and computational cost for long-time propagation.
Purpose of the Study:
- To introduce a novel time propagation method, time-dependent adaptive sampling configuration interaction (TD-ASCI), for simulating strongly correlated systems.
- To assess the accuracy of TD-ASCI by comparing computed absorption spectra with established methods.
Main Methods:
- Development and application of the time-dependent adaptive sampling configuration interaction (TD-ASCI) method.
- Utilizing the short iterative Lanczos method for unitary and stable time integration.
- Employing an efficient Fourier transform scheme based on the ESPRIT algorithm for spectral analysis.
Main Results:
- TD-ASCI successfully evaluated time-domain correlation functions for molecular systems.
- Computed dipole-allowed absorption spectra showed good agreement with reference methods.
- The ESPRIT-based Fourier transform reduced computation time for spectral analysis.
Conclusions:
- The TD-ASCI method provides an accurate and efficient approach for studying the dynamics of strongly correlated molecular systems.
- This method offers a stable and norm-conserving scheme for long-time propagation.
- TD-ASCI is a promising tool for calculating spectroscopic properties of complex quantum systems.
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