{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T04:24:36Z","timestamp":1767846276984,"version":"3.49.0"},"reference-count":36,"publisher":"AIP Publishing","issue":"3","funder":[{"name":"The International Partnership Program of Chinese Academy of Sciences","award":["116134KYSB20170048"],"award-info":[{"award-number":["116134KYSB20170048"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["21773249"],"award-info":[{"award-number":["21773249"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["91961123"],"award-info":[{"award-number":["91961123"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2020,7,21]]},"abstract":"<jats:p>We present here a synchrotron radiation vacuum ultraviolet photoionization study of the simplest alkoxy radical, CH3O, a key reaction intermediate in atmospheric and combustion chemistry. A microwave discharge fast flow tube connected to a molecular beam sampling system is employed as a chemical reactor to initiate reactions and generate radicals. The CH3O+ cation from direct ionization of the CH3O radical is detected successfully in the photoionization mass spectrum close to its ionization threshold. In addition, after identifying and removing the contribution of the 13C-isotopic formaldehyde H213CO with the same isobaric mass m\/z = 31, the high-resolution threshold photoelectron spectrum of CH3O is obtained and assigned with the aid of calculated Franck\u2013Condon factors. The adiabatic ionization energy of CH3O is determined at 10.701 eV with an accuracy of 0.005 eV.<\/jats:p>","DOI":"10.1063\/5.0016146","type":"journal-article","created":{"date-parts":[[2020,7,15]],"date-time":"2020-07-15T11:55:06Z","timestamp":1594814106000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":14,"title":["Threshold photoelectron spectroscopy of the methoxy radical"],"prefix":"10.1063","volume":"153","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2967-4960","authenticated-orcid":false,"given":"Xiaofeng","family":"Tang","sequence":"first","affiliation":[{"name":"Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics and Fine Mechanics, HFIPS, Chinese Academy of Sciences 1 , Hefei 230031, Anhui, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoxiao","family":"Lin","sequence":"additional","affiliation":[{"name":"Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics and Fine Mechanics, HFIPS, Chinese Academy of Sciences 1 , Hefei 230031, Anhui, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2915-2553","authenticated-orcid":false,"given":"Gustavo A.","family":"Garcia","sequence":"additional","affiliation":[{"name":"Synchrotron SOLEIL, L\u2019Orme des Merisiers 2 , St. Aubin, BP 48, 91192 Gif sur Yvette, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8063-8685","authenticated-orcid":false,"given":"Jean-Christophe","family":"Loison","sequence":"additional","affiliation":[{"name":"Institut des Sciences Mol\u00e9culaires (ISM), CNRS, Univ. Bordeaux 3 , 351 cours de la Lib\u00e9ration, 33400, Talence, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0932-432X","authenticated-orcid":false,"given":"Christa","family":"Fittschen","sequence":"additional","affiliation":[{"name":"University Lille, CNRS, UMR 8522, PC2A \u2013 Physicochimie des Processus de Combustion et de l\u2019Atmosph\u00e8re 4 , F-59000 Lille, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xuejun","family":"Gu","sequence":"additional","affiliation":[{"name":"Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics and Fine Mechanics, HFIPS, Chinese Academy of Sciences 1 , Hefei 230031, Anhui, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Weijun","family":"Zhang","sequence":"additional","affiliation":[{"name":"Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics and Fine Mechanics, HFIPS, Chinese Academy of Sciences 1 , Hefei 230031, Anhui, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9898-5693","authenticated-orcid":false,"given":"Laurent","family":"Nahon","sequence":"additional","affiliation":[{"name":"Synchrotron SOLEIL, L\u2019Orme des Merisiers 2 , St. Aubin, BP 48, 91192 Gif sur Yvette, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"317","published-online":{"date-parts":[[2020,7,15]]},"reference":[{"key":"2023080521471184900_c1","doi-asserted-by":"publisher","first-page":"4657","DOI":"10.1021\/cr020527p","article-title":"The atmospheric chemistry of alkoxy radicals","volume":"103","year":"2003","journal-title":"Chem. 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