{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T17:16:33Z","timestamp":1788455793693,"version":"build-2803163510"},"reference-count":35,"publisher":"American Chemical Society (ACS)","issue":"34","license":[{"start":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T00:00:00Z","timestamp":1787529600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/na","name":"JSPS Kakenhi","doi-asserted-by":"publisher","award":["23K17901"],"award-info":[{"award-number":["23K17901"]}],"id":[{"id":"10.13039\/na","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/na","name":"SPRING","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/na","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/na","name":"Union Tool and TAKEUCHI Scholarship Associations","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/na","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/na","name":"JST SPRNG","doi-asserted-by":"publisher","award":["PM2121"],"award-info":[{"award-number":["PM2121"]}],"id":[{"id":"10.13039\/na","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,2]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Excited triplet states of acene (3n\u00a0A*, n being the number of benzene rings) have recently attracted considerable attention because of their useful applications. However, 3n\u00a0A* with n &amp;gt; 5 have not been experimentally explored, due to the insolubility and instability of the higher acenes. In this study, we succeeded in detecting spin-polarized 37A* by combining the photoprecursor method using a degassed amorphous matrix of o-terphenyl and time-resolved electron spin resonance. 37A* is the longest acene among the 3n\u00a0A* observed to date. It has been clarified that 37A* is generated by preferential intersystem crossing to the in-plane sublevels and possesses zero-field splitting constants of D = 0.035 cm\u20131 and E = 0.000 cm\u20131. The D values for 3n\u00a0A* (n = 2\u20137) were found to follow a linear 1\/n-dependence, expressed as D(n)=0.180\/n+0.011 [cm\u20131], which provides a quantitative basis for the spatial extent of excitation in even higher 3n\u00a0A* states.<\/jats:p>","DOI":"10.1021\/jacs.6c06021","type":"journal-article","created":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T19:14:11Z","timestamp":1788203651000},"page":"36309-36313","source":"Crossref","is-referenced-by-count":0,"title":["Excited Triplet State\nof Heptacene Studied by Electron\nSpin Resonance"],"prefix":"10.1021","volume":"148","author":[{"given":"Mikaru","family":"Masuda","sequence":"first","affiliation":[{"name":"Niigata University , , 2-8050 Ikarashi , Nishi-ku, , ,","place":["Niigata, Niigata, Japan, 950-2181"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joel Hao","family":"Jorolan","sequence":"additional","affiliation":[{"name":"Niigata University , , 2-8050 Ikarashi , Nishi-ku, , ,","place":["Niigata, Niigata, Japan, 950-2181"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7872-3052","authenticated-orcid":true,"given":"Hironobu","family":"Hayashi","sequence":"additional","affiliation":[{"name":"National Institute for Materials Science , , Sengen 1-2-1 , , ,","place":["Tsukuba, Ibaraki, Japan, 305-0047"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2138-5902","authenticated-orcid":true,"given":"Hiroko","family":"Yamada","sequence":"additional","affiliation":[{"name":"Kyoto University , , Gokasho, , ,","place":["Uji, Kyoto, Japan, 611-0011"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7281-3049","authenticated-orcid":true,"given":"Tomoaki","family":"Miura","sequence":"additional","affiliation":[{"name":"Niigata University , , 2-8050 Ikarashi , Nishi-ku, , ,","place":["Niigata, Niigata, Japan, 950-2181"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2003-6839","authenticated-orcid":true,"given":"Tadaaki","family":"Ikoma","sequence":"additional","affiliation":[{"name":"Niigata University , , 2-8050 Ikarashi , Nishi-ku, , ,","place":["Niigata, Niigata, Japan, 950-2181"]},{"name":"Niigata University , , 2-8050 Ikarashi , Nishi-ku, , ,","place":["Niigata, Niigata, Japan, 950-2181"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,8,24]]},"reference":[{"key":"2026090312095194400_cit1","volume-title":"Principles of Molecular\nPhotochemistry, An Introduction","author":"Turro","year":"2009"},{"key":"2026090312095194400_cit2","doi-asserted-by":"crossref","DOI":"10.1039\/9781847550163","volume-title":"Aromatic Chemistry","author":"Hepworth","year":"2002"},{"key":"2026090312095194400_cit3","doi-asserted-by":"publisher","first-page":"11204","DOI":"10.1039\/D5SC02422F","article-title":"Exploring the chemistry\nof higher acenes: from synthesis\nto applications","volume":"16","author":"Hayashi","year":"2025","journal-title":"Chem. 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Phys."},{"key":"2026090312095194400_cit8","volume-title":"Modern Molecular Photochemistry\nof Organic Molecules","author":"Turro","year":"2010"},{"key":"2026090312095194400_cit9","doi-asserted-by":"publisher","first-page":"493","DOI":"10.1038\/nature25970","article-title":"Continuous-wave\nroom-temperature diamond maser","volume":"555","author":"Breeze","year":"2018","journal-title":"Nature"},{"key":"2026090312095194400_cit10","doi-asserted-by":"publisher","first-page":"41836","DOI":"10.1038\/srep41836","article-title":"Nanosecond time-resolved\ncharacterization of a pentacene-based\nroom-temperature MASER","volume":"7","author":"Salvadori","year":"2017","journal-title":"Sci. Rep."},{"key":"2026090312095194400_cit11","doi-asserted-by":"publisher","first-page":"3647","DOI":"10.1021\/acs.jpclett.1c00726","article-title":"Initializing\n214 Pure 14-Qubit Entangled Nuclear Spin\nStates in a Hyperpolarized Molecular Solid","volume":"12","author":"Kothe","year":"2021","journal-title":"J. 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Phys."}],"container-title":["Journal of the American\nChemical Society"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.acs.org\/doi\/pdf\/10.1021\/jacs.6c06021","content-type":"application\/pdf","content-version":"vor","intended-application":"unspecified"},{"URL":"https:\/\/pubs.acs.org\/jacsat\/article-pdf\/148\/34\/36309\/67390274\/jacs.6c06021.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.acs.org\/jacsat\/article-pdf\/148\/34\/36309\/67390274\/jacs.6c06021.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T16:25:26Z","timestamp":1788452726000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.acs.org\/jacsat\/article\/148\/34\/36309\/5328030\/Excited-Triplet-State-of-Heptacene-Studied-by"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,24]]},"references-count":35,"journal-issue":{"issue":"34","published-online":{"date-parts":[[2026,8,24]]},"published-print":{"date-parts":[[2026,9,2]]}},"URL":"https:\/\/doi.org\/10.1021\/jacs.6c06021","relation":{},"ISSN":["0002-7863","1520-5126"],"issn-type":[{"value":"0002-7863","type":"print"},{"value":"1520-5126","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,24]]}}}