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Updated: Apr 29, 2026

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Communication: Acceleration of coupled cluster singles and doubles via orbital-weighted least-squares tensor
Robert M Parrish1, C David Sherrill1, Edward G Hohenstein2
1Center for Computational Molecular Science and Technology, School of Chemistry and Biochemistry and School of Computational Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA.
Abstract:
We apply orbital-weighted least-squares tensor hypercontraction decomposition of the electron repulsion integrals to accelerate the coupled cluster singles and doubles (CCSD) method. Using accurate and flexible low-rank factorizations of the electron repulsion integral tensor, we are able to reduce the scaling of the most vexing particle-particle ladder term in CCSD from O(N6) to O(N5), with remarkably low error. Combined with a T1-transformed Hamiltonian, this leads to substantial practical accelerations against an optimized density-fitted CCSD implementation.
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