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Published on: June 8, 2018
Tensor factorizations of local second-order Møller-Plesset theory
Jun Yang1, Yuki Kurashige, Frederick R Manby
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA. jy459@cornell.edu
The Journal of Chemical Physics
|February 2, 2011
Summary
This study introduces novel tensor factorization methods for compact electronic wavefunction representation. These orbital-specific virtual approximations offer improved accuracy and computational efficiency in electronic structure calculations.
Area of Science:
- Computational Chemistry
- Quantum Chemistry
- Theoretical Chemistry
Background:
- Efficient electronic structure methods are crucial for understanding molecular behavior.
- Tensor representations offer a pathway to compact wavefunction descriptions.
- Local correlation theories provide approximations for large systems.
Purpose of the Study:
- To develop a low-complexity tensor representation for doubles amplitudes in local second-order Møller-Plesset perturbation theory.
- To introduce and evaluate orbital-specific virtual approximations.
- To compare the new approximations with existing methods like Pulay-Saebø.
Main Methods:
- General tensor factorization for wavefunction representation.
- Construction of orbital-specific virtual approximations (direct and full).
- Application to local second-order Møller-Plesset perturbation theory.
Main Results:
- The orbital-specific virtual approximations provide a compact representation of doubles amplitudes.
- These approximations show favorable accuracy and computational times compared to the Pulay-Saebø ansatz.
- Smooth potential energy curves were obtained for various systems and properties.
Conclusions:
- Orbital-specific virtual approximations represent a promising advancement in electronic structure calculations.
- The developed methods offer a balance between accuracy and computational cost.
- This work contributes to the development of more efficient quantum chemistry tools.
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