AI Article Synopsis
- A new version of the coupled-cluster singles and doubles (CCSD) method is introduced, designed specifically for large symmetric systems and leveraging Abelian point-group symmetry.
- It utilizes the Cholesky decomposition to efficiently handle two-electron interactions and offers two tailored strategies for calculating the particle-particle ladder term based on available computing resources.
- As a practical demonstration, the method was used to calculate the frozen-core correlation energy of buckminsterfullerene (C60), involving 240 correlated electrons across 1740 orbitals with a polarized valence triple-zeta basis set.
Article Abstract
A novel implementation of the coupled-cluster singles and doubles (CCSD) approach is presented that is specifically tailored for the treatment of large symmetric systems. It fully exploits Abelian point-group symmetry and the use of the Cholesky decomposition of the two-electron repulsion integrals. In accordance with modern CCSD algorithms, we propose two alternative strategies for the computation of the so-called particle-particle ladder term. The code is driven toward the optimal choice depending on the available hardware resources. As a large-scale application, we computed the frozen-core correlation energy of buckminsterfullerene (C60) with a polarized valence triple-zeta basis set (240 correlated electrons in 1740 orbitals).
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| http://dx.doi.org/10.1063/5.0175956 | DOI Listing |
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