{
  "abstract": "Carotenoid ultrafast photophysics has been studied for decades, but fully resolving their excited-state relaxation mechanisms remains a central, driving pursuit. Here, we investigate mini-β-carotene (m5) as a tractable model system, coupling high time-resolution transient absorption spectroscopy with ab-initio high-level multireference quantum chemistry calculations. We reveal the key and often overlooked role of the β-ionone ring-backbone torsional coordinate, which acts as a dynamic \"conjugation length control knob\" during excited-state relaxation. The torsion of these rings produces ground-state conformational heterogeneity that shapes excited-state spectroscopic signatures and governs the non-radiative relaxation pathway. Explicitly accounting for this coordinate allows us to decipher the ultrafast dynamics and provide a unified interpretation of the experimental transient absorption spectral features. We introduce a general framework based on ring-backbone coupling that bridges simple polyenes and complex carotenoids across varying chain lengths.",
  "abstract_shown": true,
  "affiliations": [
    "Dipartimento di Chimica Industriale \"Toso Montanari\", Università di Bologna - Alma Mater Studiorum, Via Piero Gobetti 85, 40129Bologna, Italy.",
    "Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133, Milano, Italy.",
    "Theoretical Chemistry Laboratory, Unit of Theoretical and Structural Physical Chemistry, Namur Institute of Structured Matter, University of Namur, B-5000Namur, Belgium.",
    "Department of Applied Chemistry for Environment, Graduate School of Science and Technology, Kwansei Gakuin University, 1 Gakuen-Uegahara, Sanda669-1330, Japan."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 11,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "V K Jaiswal",
      "orcid": "0000-0002-5090-7984"
    },
    {
      "affs": [
        1
      ],
      "name": "L Uboldi",
      "orcid": "0000-0002-6969-4894"
    },
    {
      "affs": [
        0,
        2
      ],
      "name": "A Bonvicini"
    },
    {
      "affs": [
        0
      ],
      "name": "A Nenov",
      "orcid": "0000-0003-3071-5341"
    },
    {
      "affs": [
        0
      ],
      "name": "M Garavelli",
      "orcid": "0000-0002-0796-289X"
    },
    {
      "affs": [
        0
      ],
      "name": "L Muccioli",
      "orcid": "0000-0001-9227-1059"
    },
    {
      "affs": [
        1
      ],
      "name": "D Polli",
      "orcid": "0000-0002-6960-5708"
    },
    {
      "affs": [
        3
      ],
      "name": "H Hashimoto",
      "orcid": "0000-0001-6858-9729"
    },
    {
      "affs": [
        3
      ],
      "name": "Chiasa Uragami"
    },
    {
      "affs": [
        1
      ],
      "name": "G Cerullo",
      "orcid": "0000-0002-9534-2702"
    },
    {
      "affs": [
        0
      ],
      "name": "F Segatta",
      "orcid": "0000-0003-4150-6676"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/36e8y2hjke71n.bib",
  "cited_by": 0,
  "doi": "10.1021/acs.jpclett.6c02098",
  "fulltext_url": "https://europepmc.org/articles/PMC13637073",
  "id": "36e8y2hjke71n",
  "issns": [
    "1948-7185"
  ],
  "landing_url": "https://europepmc.org/article/MED/42917148",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "3107|Spectroscopy and Quantum Chemical Studies"
    ]
  ],
  "openalex": "W7213443899",
  "pdf_url": "https://europepmc.org/articles/PMC13637073?pdf=render",
  "pmcid": "PMC13637073",
  "pmid": "42917148",
  "published": "2026-10-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/36e8y2hjke71n.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:36Z",
      "native_id": "MED:42917148",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42917148"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "openalex:3107|Spectroscopy and Quantum Chemical Studies",
      "subfield": "amo"
    }
  ],
  "title": "How β-Ionone Ring Dynamics and Conformational Heterogeneity Control Carotenoid Photophysics.",
  "title_text": "How β-Ionone Ring Dynamics and Conformational Heterogeneity Control Carotenoid Photophysics.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:20:36Z",
  "url": "https://research.draconitic.com/paper/36e8y2hjke71n",
  "venue": "The journal of physical chemistry letters",
  "versions": []
}