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arXiv · 2410.01761

Singlet Geminal Wavefunctions

Paul A. Johnson·Jean-David Moisset·Marianne Gratton·Émile Baril·Marc-Antoine Plourde·Mathis Lefebvre·Marianne Kerleaux·Paul W. Ayers·Patrick Cassam-Chenaï·Stijn De Baerdemacker·Dimitri Van Neck
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Abstract

Wavefunction forms based on products of electron pairs are usually constructed as closed-shell singlets, which is insufficient when the molecular state has a nonzero spin or when the chemistry is determined by $d$- or $f-$electrons. A set of two-electron forms are considered as explicit couplings of second-quantized operators to open-shell singlets. Geminal wavefunctions are constructed and their structure is elaborated. Numerical results for small model systems clearly demonstrate improvement over closed-shell singlet pairs.

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Paul A. Johnson, Jean-David Moisset, Marianne Gratton, Émile Baril, Marc-Antoine Plourde, Mathis Lefebvre, Marianne Kerleaux, Paul W. Ayers, Patrick Cassam-Chenaï, Stijn De Baerdemacker, Dimitri Van Neck. 2024-10-02. Singlet Geminal Wavefunctions. https://arxiv.org/abs/2410.01761

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