{
  "abstract": "Machine-learned exchange--correlation (XC) functionals offer a route to improve Kohn--Sham density-functional theory without incurring the cost of explicitly correlated electronic-structure methods. Their use in production simulation codes, however, requires a well-defined mapping between the learned model and the host-code density representation. We formulate and implement a Skala-1.1 interface in CP2K through the external GauXC library. CP2K supplies the geometry, Gaussian basis, spin-resolved atomic-orbital density matrix, and communicator, while GauXC evaluates the XC energy, atomic-orbital potential matrix, and available nuclear derivatives. The interface accepts both all-electron and valence-only density matrices. The latter may arise from separable dual-space pseudopotentials or molecular effective-core potentials. Implementation errors are isolated from functional differences by comparing the Perdew--Burke--Ernzerhof (PBE) functional evaluated through GauXC with native CP2K PBE. The resulting interface gives consistent energies, forces validated against finite-difference total-energy checks, and force-based molecular-virial diagnostics for representative molecular cases. The dietGMTKN55 benchmark suite is evaluated with an all-electron Gaussian augmented plane-wave treatment for elements up to bromine and def2 effective-core potentials for the heavier elements. The resulting aggregate mean absolute deviation of 1.255 kcal/mol is within 0.012 kcal/mol of the corresponding Skala reference value of 1.243 kcal/mol. This work establishes a validated molecular implementation of Skala in CP2K through GauXC.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.19033",
  "author_total": 9,
  "authors": [
    {
      "name": "Franz Pöschel"
    },
    {
      "name": "Johann Pototschnig"
    },
    {
      "name": "Frederick Stein"
    },
    {
      "name": "Andreas Knüpfer"
    },
    {
      "name": "Thijs Vogels"
    },
    {
      "name": "Stefano Battaglia"
    },
    {
      "name": "Sebastian Ehlert"
    },
    {
      "name": "Jürg Hutter"
    },
    {
      "name": "Thomas D. Kühne"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/b92k9g02wf72a.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.19033",
  "fulltext_url": null,
  "id": "b92k9g02wf72a",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.19033",
  "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",
      "cond-mat.dis-nn"
    ],
    [
      "arxiv",
      "cond-mat.mtrl-sci"
    ],
    [
      "arxiv",
      "physics.chem-ph"
    ],
    [
      "arxiv",
      "physics.comp-ph"
    ],
    [
      "arxiv",
      "quant-ph"
    ],
    [
      "openalex",
      "3107|Advanced Chemical Physics Studies"
    ]
  ],
  "openalex": "W7203923073",
  "pdf_url": "https://arxiv.org/pdf/2608.19033",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-28",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/b92k9g02wf72a.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:12Z",
      "native_id": "2608.19033",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.19033"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "arxiv:physics.chem-ph",
      "subfield": "physical"
    },
    {
      "field": "physics",
      "origin": "arxiv:physics.comp-ph",
      "subfield": "computational"
    },
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.dis-nn",
      "subfield": "condensed-matter"
    },
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Molecular Implementation of the Machine-Learned Skala Exchange-Correlation Functional in CP2K through GauXC",
  "title_text": "Molecular Implementation of the Machine-Learned Skala Exchange-Correlation Functional in CP2K through GauXC",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:12Z",
  "url": "https://research.draconitic.com/paper/b92k9g02wf72a",
  "venue": "arXiv",
  "versions": []
}