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arXiv · 2405.06776

Combining complex conjugation, time-reversal, and spin symmetry projection of coupled cluster wave functions

Ruiheng Song·Thomas M. Henderson·Gustavo E. Scuseria
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Abstract

Complex conjugation symmetry breaking and restoration generate two non-orthogonal configurations at the Hartree-Fock level that can capture static correlation naturally. In conjunction with broken spin-symmetry coupled cluster theory, the symmetry-projected wave function shows good agreement with full configuration interaction in beryllium hydride insertion, lithium fluoride dissociation, and symmetric stretching of tetrahedral H$_4$. By adding spin flip projection, we can also recover time reversal symmetry in the same coupled cluster framework.

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Ruiheng Song, Thomas M. Henderson, Gustavo E. Scuseria. 2024-05-10. Combining complex conjugation, time-reversal, and spin symmetry projection of coupled cluster wave functions. https://arxiv.org/abs/2405.06776

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