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DOE OSTI · 2349223

Correlated pair ansatz with a binary tree structure

Dutta, Rishab·Gao, Fei·Khamoshi, Armin·Henderson, Thomas M.·Scuseria, Gustavo E.
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Abstract

We develop an efficient algorithm to implement the recently introduced binary tree state (BTS) ansatz on a classical computer. BTS allows a simple approximation to permanents arising from the computationally intractable antisymmetric product of interacting geminals and respects size-consistency. We show how to compute BTS overlap and reduced density matrices efficiently. We also explore two routes for developing correlated BTS approaches: Jastrow coupled cluster on BTS and linear combinations of BT states. Here, the resulting methods show great promise in benchmark applications to the reduced Bardeen–Cooper–Schrieffer Hamiltonian and the one-dimensional XXZ Heisenberg Hamiltonian.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYAntisymmetrized geminal powerCoupled-cluster methodsGeminal wavefunction

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Dutta, Rishab, Gao, Fei, Khamoshi, Armin, Henderson, Thomas M., Scuseria, Gustavo E.. 2024-02-29. Correlated pair ansatz with a binary tree structure. https://doi.org/10.1063/5.0185375

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