{
  "abstract": "Recently, Surjuse and Valeev [J. Chem. Theory Comput. 22, 3443-3452 (2026).] suggested to use a simple superposition of atomic potentials to account for the two-electron picture-change error in one-electron exact two-component (SAP-X2C) theory. Herein, we generalize this ansatz to analytical derivative theory and apply SAP-X2C to molecular spectroscopy. The accuracy is assessed for NMR, EPR, Mössbauer, UV/vis, as well as X-ray absorption spectroscopy. A thorough comparison with four-component results and the even simpler screened nuclear spin-orbit (SNSO) approximation reveals that both SNSO-X2C and SAP-X2C perform excellently for spectroscopic properties, with SAP-X2C yielding slightly lower errors. Another major advantage is its well defined thermodynamic limit and less empirical nature. Therefore, SAP-X2C may be expected to become the default choice to mitigate the two-electron picture-change error in density functional theory approaches for spectroscopy thanks to its accuracy, simplicity, and efficiency. More complicated approaches to account for this error based on atomic mean-field ansätze may still be relevant for high-level correlated methods and highly accurate thermochemistry.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: J. Chem. Theory Comput. 22 (18), 9608-9625 (2026)",
  "arxiv": "2607.03814",
  "author_total": 2,
  "authors": [
    {
      "name": "Yannick J. Franzke"
    },
    {
      "name": "Christof Holzer"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/6kssm811z3dkv.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2607.03814",
  "fulltext_url": null,
  "id": "6kssm811z3dkv",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2607.03814",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.chem-ph"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2607.03814",
  "pmcid": null,
  "pmid": null,
  "published": "2026-08-13",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/6kssm811z3dkv.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:24:11Z",
      "native_id": "2607.03814",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2607.03814"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "arxiv:physics.chem-ph",
      "subfield": "physical"
    }
  ],
  "title": "Application of SAP-X2C to Spectroscopy and Comparison to Screened Nuclear Spin-Orbit Approximations",
  "title_text": "Application of SAP-X2C to Spectroscopy and Comparison to Screened Nuclear Spin-Orbit Approximations",
  "type": "preprint",
  "updated_at": "2026-10-30T12:24:11Z",
  "url": "https://research.draconitic.com/paper/6kssm811z3dkv",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1021/acs.jctc.6c01360",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}