{
  "abstract": "We report a quantum-chemical investigation into the chemiluminescence mechanism of cyclometalated Ir (III) Schiff base complexes, promising chemiluminophores for biological imaging. The reaction proceeds via ring-opening of a key oxaziridine intermediate to yield a singlet diradical, which undergoes rapid intersystem crossing (ISC) to its triplet counterpart, followed by deprotonation to generate the emissive triplet product. Within this process, the Ir (III) center not only activates the imine via Lewis-acid coordination but also reverses the singlet-triplet energy ordering of the diradical intermediate, rendering the triplet diradical thermodynamically favored with an equilibrium population of ca. 86% at ambient temperature. The heavy-atom effect of iridium provides substantial spin-orbit coupling; combined with a low-lying minimum-energy crossing point (MECP, 1.7 kcal mol -1 ) and large Franck-Condon-weighted density of states, this accelerates ISC to a rate of 1.5 × 1011 s -1 . Notably, the two radical centers are separated by an 𝑠𝑝3-hybridized carbon, and the intervening C-H bond is strongly polarized by the adjacent O-centered radical, rendering deprotonation nearly barrierless. These collective computational findings establish design principles for two distinct goals: stabilizing diradical species to extend their lifetimes for EPR characterization, and informing the rational development of non-precious-metal chemiluminescent systems.",
  "abstract_shown": true,
  "affiliations": [
    "College of Materials Science and Engineering",
    "Shenzhen University",
    "Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials",
    "Fudan University",
    "School of Science and Engineering",
    "The Chinese University of Hong Kong"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Heng-Ding Wang"
    },
    {
      "affs": [
        2,
        3
      ],
      "name": "Ziyan Ye"
    },
    {
      "affs": [
        4,
        5
      ],
      "name": "Chiyuan Wei"
    },
    {
      "affs": [
        2,
        3
      ],
      "name": "Wei Fang"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Mingle Li"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Xiaoqiang Chen"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Xiaojun Peng"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8gfhgrsx6ag54.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15010118/v1",
  "fulltext_url": null,
  "id": "8gfhgrsx6ag54",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010118/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",
      "2208|Organic Light-Emitting Diodes Research"
    ]
  ],
  "openalex": "W7221121001",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15010118/v1",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-08",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/8gfhgrsx6ag54.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:22Z",
      "native_id": "10.26434/chemrxiv.15010118",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010118/v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "source:chemrxiv",
      "subfield": "general"
    }
  ],
  "title": "High-Spin Diradical-Dominated Chemiluminescence",
  "title_text": "High-Spin Diradical-Dominated Chemiluminescence",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:22Z",
  "url": "https://research.draconitic.com/paper/8gfhgrsx6ag54",
  "venue": "ChemRxiv",
  "versions": []
}