{
  "abstract": "Chemical reactions involving protonation are ubiquitous in nature, yet their accurate description using static quantum-chemical methods remains challenging. Here, we derive a temperature-resolved aqueous free energy of H+ (G◦,aq H+ ) by combining experimental pKa data for 12 ammonium acids over 293–333 K with a high-level composite quantum-chemical protocol based on LNO-CCSD(T)/CBS energies, CPCM solvation, and conformational thermochemistry. Thermodynamic analysis gives G◦,aq H+ = −270.0 kcal/mol at 298 K, within 0.3 kcal/mol of the canonical literature value (Tissandier et al., 1998). The fitted parameters are robust under cross-validation, and validation on an independent set of 18 acids yields a mean absolute error of 0.70 pKa units.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "name": "Khaled Jaradat",
      "orcid": "0000-0002-0148-4022"
    },
    {
      "name": "Bence Balázs Mészáros"
    },
    {
      "name": "János Daru"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/b1bwt3mjyh6hs.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15009422/v1",
  "fulltext_url": null,
  "id": "b1bwt3mjyh6hs",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009422/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": "W7214144446",
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-24",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/b1bwt3mjyh6hs.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:21Z",
      "native_id": "10.26434/chemrxiv.15009422",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009422/v1"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "openalex:3107|Advanced Chemical Physics Studies",
      "subfield": "amo"
    }
  ],
  "title": "Proton Solvation Thermochemistry: A Temperature-Resolved Calibration from Ammonium Acids",
  "title_text": "Proton Solvation Thermochemistry: A Temperature-Resolved Calibration from Ammonium Acids",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:21Z",
  "url": "https://research.draconitic.com/paper/b1bwt3mjyh6hs",
  "venue": "ChemRxiv",
  "versions": []
}