{
  "abstract": "Gas-phase neutral and ion–water clusters are fundamental models for hydrogen bonding, many-body interactions, proton transfer, and ionic hydration in liquid water and aqueous environments, and they are stringent tests for density functional approximations: semilocal functionals without exact exchange or an explicit self-interaction correction have typically described their interaction and binding energies poorly. The non-self-consistent SCAN@HF approach was recently shown to describe water clusters and liquid water with high accuracy, but subsequent analysis demonstrated that this performance arises largely from cancellation between a substantial functional-driven error and an opposing error introduced by the overlocalized Hartree–Fock density. Here we assess a new self-consistent meta-generalized gradient approximation, bonded-norm r2SCAN (bn-r2SCAN), for neutral, protonated, and deprotonated water clusters and for alkali-and halide–water complexes. bn-r2SCAN approaches chemical accuracy across these diverse systems, with overall mean unsigned binding-energy errors of 0.33− 1.04 kcal/mol for the benchmark sets considered, and substantially improves upon r2SCAN. Error decomposition shows that this accuracy does not rest on the near-total cancellation of large opposing errors underlying SCAN@HF: for the BEGDB dataset, the mean functional-and density-driven errors of bn-r2SCAN are 0.34 and −0.89 kcal/mol, and even for the largest clusters both remain a small fraction of the total binding energy, whereas for SCAN@HF the functional-driven error of SCAN and the nonvariational density over-localization introduced by the Hartree–Fock density each exceed 5 kcal/mol and cancel to within a few tenths. Notably, bn-r2SCAN was parametrized using band gaps and lattice constants (not weak bonds) of simple solids, making its performance for aqueous clusters a demanding test of transferability and identifying it as a self-consistent and computationally efficient route to modeling water and aqueous systems.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "name": "Chandra Shahi",
      "orcid": "0000-0002-6431-2607"
    },
    {
      "name": "Adrienn Ruzsinszky"
    },
    {
      "name": "John P. Perdew"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/ecmacgebnd0zc.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15009326/v1",
  "fulltext_url": null,
  "id": "ecmacgebnd0zc",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009326/v1",
  "language": null,
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "3107|Advanced Chemical Physics Studies"
    ]
  ],
  "openalex": "W7214094230",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15009326/v1",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-22",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/ecmacgebnd0zc.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:21Z",
      "native_id": "10.26434/chemrxiv.15009326",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009326/v1"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "openalex:3107|Advanced Chemical Physics Studies",
      "subfield": "amo"
    }
  ],
  "title": "Approaching Chemical Accuracy for Neutral and Ionic Water Clusters with the bn-r2SCAN Meta-GGA",
  "title_text": "Approaching Chemical Accuracy for Neutral and Ionic Water Clusters with the bn-r2SCAN Meta-GGA",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:21Z",
  "url": "https://research.draconitic.com/paper/ecmacgebnd0zc",
  "venue": "ChemRxiv",
  "versions": []
}