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arXiv · 2401.11935

Two Determinant Distinguishable Cluster

Thomas Schraivogel·Daniel Kats
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Abstract

A two reference determinant version of the distinguishable cluster with singles and doubles (DCSD) has been developed. We have implemented the two determinant distinguishable cluster (2D-DCSD) and the corresponding traditional 2D-CCSD method in a new open-source package written in Julia called ElemCo.jl. The methods were benchmarked on singlet and triplet excited states of valence and Rydberg character, as well as for singlet-triplet gaps of diradicals. It is demonstrated that the distinguishable cluster approximation improves the accuracy of 2D-CCSD.

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Thomas Schraivogel, Daniel Kats. 2024-01-22. Two Determinant Distinguishable Cluster. https://doi.org/10.1063/5.0199274

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