{
  "abstract": "Californium (Cf3+) complexes with several Keggin-type polyoxometalate (POM) ligands have been synthesized and characterized, providing the first serial approach to Cf chemistry and a unique occasion to contrast its coordination properties with that of other felements. Contrary to trivalent lanthanides, americium and curium, californium yields a higher diversity of structures. Using microgram amounts of 249Cf, nine new structures containing Cf3+ have been obtained with the POM ligands [PW11O39]7-, [SiW11O39]8-, [GeW11O39]8-, and [BW11O39]9-, representing the largest series of Cf compounds ever isolated and significantly expanding experimental data on POM compounds with heavy actinides. Cf3+ crystallizes as the typical 8coordinate sandwich complexes with Keggin ions, [Cf(XW11O39)2]n-, but the long-range bond distances and twist angles of the Cf-POM complexes depart from any previous case reported. Comparative compounds obtained with the nearly isometric lanthanides also underline the uniqueness of the Cf3+ compounds beyond the ion size effects. The now extended family of [M(XW11O39)2]n- complexes also revealed previously unobserved topological isomers in such complexes, defined here as iota (ι) and omega (ω), with the Cf complexes’ isomerism often differing from the other f-elements. This first series of isotypic Cf compounds, CsyHz[Cf(XW11O39)2]·nH2O, (X = P5+, Si4+, Ge4+, or B3+), combined with structures previously obtained with Am3+, Cm3+, and lanthanides allows for the determination of bond valence sum (BVS) parameters for Cf3+ as well as the experimental determination of its 8-coordinate ionic radius: 1.066 ± 0.004 Å.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 2,
  "authors": [
    {
      "name": "Ian Colliard",
      "orcid": "0000-0003-1883-1155"
    },
    {
      "name": "Gauthier J. -P. Deblonde",
      "orcid": "0000-0002-0825-8714"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0emcr765xcpf2.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15010944/v1",
  "fulltext_url": null,
  "id": "0emcr765xcpf2",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010944/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",
      "2505|Polyoxometalates: Synthesis and Applications"
    ]
  ],
  "openalex": "W7223297021",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15010944/v1",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-23",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/0emcr765xcpf2.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:26Z",
      "native_id": "10.26434/chemrxiv.15010944",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010944/v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:2505|Polyoxometalates: Synthesis and Applications",
      "subfield": "materials-polymers"
    }
  ],
  "title": "Structural and Spectroscopic Characterization of Californium Polyoxometalate Compounds",
  "title_text": "Structural and Spectroscopic Characterization of Californium Polyoxometalate Compounds",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:26Z",
  "url": "https://research.draconitic.com/paper/0emcr765xcpf2",
  "venue": "ChemRxiv",
  "versions": []
}