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Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
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A coupled cluster framework for electrons and phonons
Alec F White1, Yang Gao2, Austin J Minnich2
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
The Journal of Chemical Physics
|December 15, 2020
Summary
We developed a new coupled cluster theory to model electron-phonon interactions in materials. This approach accurately describes electronic and vibrational properties, advancing computational materials science.
Area of Science:
- Computational Physics
- Quantum Chemistry
- Materials Science
Background:
- Electron-phonon interactions are crucial for understanding material properties.
- Accurate theoretical methods are needed to model these coupled systems.
Purpose of the Study:
- To develop and apply a coupled cluster framework for electron-phonon systems.
- To benchmark coupled cluster approximations for accuracy.
- To implement ab initio calculations for solids.
Main Methods:
- Equation-of-motion coupled cluster theory.
- Hubbard-Holstein model for benchmarking.
- Implementation using crystalline Gaussian type orbitals in PySCF.
Main Results:
- The coupled cluster framework accurately describes neutral and charged excitations.
- Coupled cluster approximations perform well for weak to moderate electron-phonon coupling.
- Preliminary results for finite-size models of diamond with linear coupling are presented.
Conclusions:
- The developed coupled cluster theory is a powerful tool for studying electron-phonon interactions.
- The method shows promise for ab initio calculations on solids.
- Implementation within PySCF facilitates further research.
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