{"paper":{"title":"Spin-adapted neural network backflow for symmetry-preserving simulations of strongly correlated electrons","license":"http://creativecommons.org/licenses/by/4.0/","headline":"A spin-adapted neural network backflow ansatz enforces exact spin symmetry in variational wavefunctions for strongly correlated electrons.","cross_cats":["cond-mat.str-el"],"primary_cat":"physics.chem-ph","authors_text":"Bohan Zhang, Wei-Hai Fang, Yunzhi Li, Zhendong Li, Zibo Wu","submitted_at":"2026-04-08T09:02:49Z","abstract_excerpt":"Strongly correlated molecules often contain dense manifolds of low-lying spin states, making total-spin symmetry essential for predictive electronic-structure theory. Neural-network quantum states provide flexible variational wavefunctions, but commonly used fermionic architectures do not enforce this symmetry and can therefore converge to spin-contaminated states with misleading energies and properties. Here we introduce a spin-adapted neural-network backflow (SA-NNBF) ansatz in second quantization, which combines configuration-dependent spatial orbitals with a compressed spin eigenfunction. "},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"Applications to prototypical strongly correlated molecules demonstrate that SA-NNBF consistently outperforms standard NNBF with a similar number of parameters. Furthermore, it surpasses the accuracy of the state-of-the-art spin-adapted density matrix renormalization group (SA-DMRG) algorithm for FeMoco with a significantly reduced computational resource.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"That the introduced tensor compression algorithm for spin eigenfunctions and the particle-hole duality representation preserve both the exact spin symmetry and the variational accuracy of the full wavefunction when applied to systems with more than one hundred electrons.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"SA-NNBF creates fully antisymmetric, spin-symmetric neural wavefunctions via sum-of-products spin eigenfunctions and tensor compression, enabling VMC calculations that outperform standard NNBF and SA-DMRG on systems with over 100 electrons including FeMoco.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"A spin-adapted neural network backflow ansatz enforces exact spin symmetry in variational wavefunctions for strongly correlated electrons.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"4940584b00cb1f2b7fdc1939a9fad010580c2171615edca7a926ea80d97b2a85"},"source":{"id":"2604.06841","kind":"arxiv","version":2},"verdict":{"id":"0daa9b71-028a-4a69-adc9-87ed893f37df","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-10T17:23:10.036216Z","strongest_claim":"Applications to prototypical strongly correlated molecules demonstrate that SA-NNBF consistently outperforms standard NNBF with a similar number of parameters. Furthermore, it surpasses the accuracy of the state-of-the-art spin-adapted density matrix renormalization group (SA-DMRG) algorithm for FeMoco with a significantly reduced computational resource.","one_line_summary":"SA-NNBF creates fully antisymmetric, spin-symmetric neural wavefunctions via sum-of-products spin eigenfunctions and tensor compression, enabling VMC calculations that outperform standard NNBF and SA-DMRG on systems with over 100 electrons including FeMoco.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"That the introduced tensor compression algorithm for spin eigenfunctions and the particle-hole duality representation preserve both the exact spin symmetry and the variational accuracy of the full wavefunction when applied to systems with more than one hundred electrons.","pith_extraction_headline":"A spin-adapted neural network backflow ansatz enforces exact spin symmetry in variational wavefunctions for strongly correlated electrons."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2604.06841/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}