{
  "abstract": "In alkali fluoride solutions, crown ethers are widely assumed to generate \"naked\" anions by capturing cations, yet direct evidence for complete ion-pair dissociation is limited. We combine 19F Nuclear Magnetic Resonance (NMR) and multiscale modeling on aqueous NaF and KF with 18crown-6 (18C6). Fluoride diffusion slows on crown addition, scaling linearly with the crownbound cation fraction across both salts and extrapolating to zero without complexation. The 19F chemical shifts independently establish this retained ion pairing. For KF, the signal moves away from the free-ion baseline, the wrong direction for liberation. While NaF responds more weakly, the theoretical chemical shift profile shows that the crown-bound cation carries a shielding contact (CIP) region and a deshielding solvent-shared (SIP) region whose cancellation flattens the response. Molecular dynamics confirm reduced but persistent contact pairing. Crown ethers thus suppress contact pairing while retaining both solvent-shared and residual contact associations with the sequestered cation.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "name": "Malgorzata Musial",
      "orcid": "0000-0002-1624-6617"
    },
    {
      "name": "Christopher L. Suiter",
      "orcid": "0000-0003-3354-3258"
    },
    {
      "name": "Jason Widegren",
      "orcid": "0000-0003-1077-7035"
    },
    {
      "name": "Demian Riccardi",
      "orcid": "0000-0001-8095-7803"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0c40tpgv8ttqh.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15008835/v1",
  "fulltext_url": null,
  "id": "0c40tpgv8ttqh",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15008835/v1",
  "language": null,
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "1605|Supramolecular Chemistry and Complexes"
    ]
  ],
  "openalex": "W7213237923",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15008835/v1",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-15",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/0c40tpgv8ttqh.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:19Z",
      "native_id": "10.26434/chemrxiv.15008835",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15008835/v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:1605|Supramolecular Chemistry and Complexes",
      "subfield": "organic"
    }
  ],
  "title": "Do crown ethers fully dissociate ion pairs in aqueous solution?",
  "title_text": "Do crown ethers fully dissociate ion pairs in aqueous solution?",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:19Z",
  "url": "https://research.draconitic.com/paper/0c40tpgv8ttqh",
  "venue": "ChemRxiv",
  "versions": []
}