{"paper":{"title":"Controlling Projection-Space Artifacts in DFT+U via Projection-Consistent U_{eff}","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"Making U_eff consistent with each projection space removes artificial errors in DFT+U total energies, magnetic ordering, and phase stability.","cross_cats":["cond-mat.mtrl-sci"],"primary_cat":"cond-mat.str-el","authors_text":"Kenneth Park, Manjula Raman","submitted_at":"2026-03-07T21:00:39Z","abstract_excerpt":"Density functional theory augmented with a Hubbard correction (DFT+U) is widely used to treat localized electronic states, but its predictions are often sensitive to the choice of the local projection space defining the correlated subspace. This sensitivity poses a practical challenge for computational reproducibility, particularly when projection parameters vary across codes, basis sets, or materials. In this work, we systematically investigate how the effective on-site Coulomb interaction $U_{\\mathrm{eff}}$, determined \\textit{ab initio} using constrained density functional theory, depends o"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"Applying a single fixed U_eff across different projection choices introduces artificial projection-driven errors in total energies, including spurious magnetic ordering transitions and unphysical sensitivity of phase stability. These artifacts are eliminated when U_eff is determined in an internally consistent manner for each projection space.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"That the projection-size dependence of U_eff observed in all-electron APW+lo calculations on TiO2 and MnO2 generalizes to other materials, codes, and basis sets, and that constrained DFT accurately isolates the orbital-relaxation effect without confounding errors from the underlying functional.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Determining U_eff consistently for each projection space in DFT+U eliminates projection-driven artifacts in energies, phase stability, and magnetic ordering for rutile/anatase TiO2 and beta-MnO2.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Making U_eff consistent with each projection space removes artificial errors in DFT+U total energies, magnetic ordering, and phase stability.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"92c61d67b30c1a3b6bbaf61dcda27da67deb64969c9f9e37991070801217e4fd"},"source":{"id":"2603.07340","kind":"arxiv","version":2},"verdict":{"id":"40c4f876-e740-4868-85f5-2f3ed6be57db","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-15T14:31:25.329255Z","strongest_claim":"Applying a single fixed U_eff across different projection choices introduces artificial projection-driven errors in total energies, including spurious magnetic ordering transitions and unphysical sensitivity of phase stability. These artifacts are eliminated when U_eff is determined in an internally consistent manner for each projection space.","one_line_summary":"Determining U_eff consistently for each projection space in DFT+U eliminates projection-driven artifacts in energies, phase stability, and magnetic ordering for rutile/anatase TiO2 and beta-MnO2.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"That the projection-size dependence of U_eff observed in all-electron APW+lo calculations on TiO2 and MnO2 generalizes to other materials, codes, and basis sets, and that constrained DFT accurately isolates the orbital-relaxation effect without confounding errors from the underlying functional.","pith_extraction_headline":"Making U_eff consistent with each projection space removes artificial errors in DFT+U total energies, magnetic ordering, and phase stability."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2603.07340/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":2,"snapshot_sha256":"fa940d0321de88be2511cc9bd70e4fcb9111e2113c0cc2d21293bb483fd01cab"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}