{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T01:58:29Z","timestamp":1793411909320,"version":"4.5.0"},"reference-count":44,"publisher":"American Chemical Society (ACS)","issue":"30","license":[{"start":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T00:00:00Z","timestamp":1784592000000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-029"},{"start":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T00:00:00Z","timestamp":1784592000000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-037"},{"start":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T00:00:00Z","timestamp":1784592000000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-045"}],"funder":[{"name":"Bavarian Initiative \u201cSolar Technologies Go Hybrid\u201d"},{"DOI":"10.13039\/100000001","name":"US National Science Foundation","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,5]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Understanding how molecular structure governs photoinduced spin evolution in organic diradicals is essential for the rational design of spin-responsive molecular materials. Here, we investigate temperature-dependent excited-state relaxation dynamics of syn- and anti-indenoindenodibenzothiophene (IIDBT) diradicaloids using variable-temperature steady-state and transient absorption spectroscopies. Vibronic progressions in the high-energy, nonfrontier-orbital \u03c0\u2013\u03c0* transition absorptions and low-energy frontier-orbital transition absorptions prompt strong couplings between electronic excitation, on one hand, and molecular vibrations, on the other hand. With the help of ultrafast spectroscopy, we identified multistep excited-state relaxation pathways including a \u201chot\u201d singlet excited state, an intermediate state of mixed electronic and spin character, and a long-lived triplet excited state, following either low- or high-energy excitations. Notably, intersystem crossing (ISC) in IIDBT diradicaloids is enabled by vibrationally activated spin\u2013orbit coupling, in which spin-vibronic coupling enhances singlet\u2013triplet mixing along nuclear coordinates, leading to a fast and efficient interconversion between singlet and triplet excited states. Molecular control over both the vibronic coupling strength and spin evolution is also emphasized. This work establishes a clear experimental link between molecular vibration and spin-dependent excited-state dynamics in organic diradicals, providing a general framework for understanding and controlling ISC in open-shell organic systems.<\/jats:p>","DOI":"10.1021\/jacs.6c03953","type":"journal-article","created":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T01:35:11Z","timestamp":1784684111000},"page":"31829-31836","source":"Crossref","is-referenced-by-count":1,"title":["Spin-Vibronic Coupling\nin Indenoindenodibenzothiophene\nDiradicaloids"],"prefix":"10.1021","volume":"148","author":[{"given":"Liping","family":"Liu","sequence":"first","affiliation":[{"name":"Hainan University , , ,","place":["Haikou, China, 570228"]},{"name":"Friedrich-Alexander University Erlangen-Nu\u0308rnberg , , Egerlandstrasse 3 , ,","place":["Erlangen, Germany, 91058"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guanglin","family":"Huang","sequence":"additional","affiliation":[{"name":"Huazhong University of Science and Technology (HUST) , , ,","place":["Wuhan, China, 430074"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yongqiang","family":"Chai","sequence":"additional","affiliation":[{"name":"Friedrich-Alexander University Erlangen-Nu\u0308rnberg , , Egerlandstrasse 3 , ,","place":["Erlangen, Germany, 91058"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xing","family":"Lu","sequence":"additional","affiliation":[{"name":"Hainan University , , ,","place":["Haikou, China, 570228"]},{"name":"Huazhong University of Science and Technology (HUST) , , ,","place":["Wuhan, China, 430074"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-8667-0741","authenticated-orcid":true,"given":"Efrain","family":"Vidal Jr","sequence":"additional","affiliation":[{"name":"University of Oregon , , , ,","place":["Eugene, Oregon, United States, 97403-1253"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7027-4141","authenticated-orcid":true,"given":"Michael M.","family":"Haley","sequence":"additional","affiliation":[{"name":"University of Oregon , , , ,","place":["Eugene, Oregon, United States, 97403-1253"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3960-1765","authenticated-orcid":true,"given":"Dirk M.","family":"Guldi","sequence":"additional","affiliation":[{"name":"Friedrich-Alexander University Erlangen-Nu\u0308rnberg , , Egerlandstrasse 3 , ,","place":["Erlangen, Germany, 91058"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,7,21]]},"reference":[{"key":"2026080511112369800_cit1","doi-asserted-by":"publisher","first-page":"7011","DOI":"10.1021\/cr400056a","article-title":"Diradicals","volume":"113","author":"Abe","year":"2013","journal-title":"Chem. Rev."},{"key":"2026080511112369800_cit2","doi-asserted-by":"publisher","DOI":"10.1002\/poc.4114","article-title":"Learning how to\nfine-tune diradical properties by structure\nrefinement","volume":"33","author":"Dressler","year":"2020","journal-title":"J. Phys. Org. Chem."},{"key":"2026080511112369800_cit3","doi-asserted-by":"crossref","DOI":"10.1201\/9781003277248","volume-title":"Diradicaloids","author":"Wu","year":"2022"},{"key":"2026080511112369800_cit4","doi-asserted-by":"publisher","first-page":"10468","DOI":"10.1021\/acs.chemrev.3c00255","article-title":"Heteroatom-Based Diradical(oid)s","volume":"123","author":"Hinz","year":"2023","journal-title":"Chem. Rev."},{"key":"2026080511112369800_cit5","doi-asserted-by":"publisher","first-page":"11291","DOI":"10.1021\/acs.chemrev.9b00260","article-title":"Do Diradicals Behave\nLike Radicals?","volume":"119","author":"Stuyver","year":"2019","journal-title":"Chem. Rev."},{"key":"2026080511112369800_cit6","doi-asserted-by":"publisher","first-page":"890","DOI":"10.1021\/acscentsci.4c00284","article-title":"Optically\nDistinguishable\nElectronic Spin-isomers of a Stable Organic Diradical","volume":"10","author":"Shimizu","year":"2024","journal-title":"ACS Cent. Sci."},{"key":"2026080511112369800_cit7","doi-asserted-by":"publisher","first-page":"1353","DOI":"10.1016\/j.chempr.2020.02.010","article-title":"Diindenoanthracene\nDiradicaloids Enable Rational, Incremental Tuning of Their Singlet-Triplet\nEnergy Gaps","volume":"6","author":"Dressler","year":"2020","journal-title":"Chem"},{"key":"2026080511112369800_cit8","doi-asserted-by":"publisher","first-page":"14913","DOI":"10.1021\/ja304618v","article-title":"Kinetically blocked\nstable heptazethrene and octazethrene: closed-shell or open-shell\nin the ground state?","volume":"134","author":"Li","year":"2012","journal-title":"J. Am. Chem. 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Chem.\nA"},{"key":"2026080511112369800_cit41","doi-asserted-by":"publisher","first-page":"2192","DOI":"10.1021\/jp026189d","article-title":"Mechanism\nof Photosensitized Generation of Singlet Oxygen during Oxygen Quenching\nof Triplet States and the General Dependence of the Rate Constants\nand Efficiencies of O2(1\u03a3g+), O2(1\u0394g), and O2(3\u03a3g\u2013) Formation\non Sensitizer Triplet State Energy and Oxidation Potential","volume":"107","author":"Schweitzer","year":"2003","journal-title":"J. Phys. Chem. A"},{"key":"2026080511112369800_cit42","doi-asserted-by":"publisher","first-page":"4058","DOI":"10.1063\/1.1677816","article-title":"Theory of\nIntersystem Crossing in\nAromatic Hydrocarbons","volume":"56","author":"Lawetz","year":"1972","journal-title":"J. Chem. 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