{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T19:50:14Z","timestamp":1771271414328,"version":"3.50.1"},"reference-count":63,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,8,8]],"date-time":"2022-08-08T00:00:00Z","timestamp":1659916800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["UIDB\/QUI\/0313\/2020"],"award-info":[{"award-number":["UIDB\/QUI\/0313\/2020"]}]},{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["UIDP\/QUI\/0313\/2020"],"award-info":[{"award-number":["UIDP\/QUI\/0313\/2020"]}]},{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["LA\/P\/0056\/2020"],"award-info":[{"award-number":["LA\/P\/0056\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Atmosphere"],"abstract":"<jats:p>Accurate calculation of rate constants for gas-phase OH-oxidation reactions of fluorinated compounds is crucial for the understanding of atmospheric processes that are subject of the Kigali Agreement. Here, we have determined two such rate constants for two hydrofluoroketones, HFK-447mcc and HFK-465mc. The calculations were performed with a cost-effective multiconformer transition state theory protocol coupled with the constrained transition state randomization sampling method. The calculated rate constants of k(HO\u2022+HFK-447mcc)=3.1\u00d710\u221215cm3molecule\u22121s\u22121 and k(HO\u2022+HFK-465mc)=3.2\u00d710\u221214cm3molecule\u22121s\u22121 at 298.15 K imply an atmospheric lifetime of 10 years and 1 year, respectively. To our knowledge, these rate constants have never been determined experimentally or theoretically, and the similarity between the ratios of these two rate constants and of the well-studied acetone and diethyl ketone suggest the validity of our approach toward obtaining accurate rate constants and branching ratios.<\/jats:p>","DOI":"10.3390\/atmos13081256","type":"journal-article","created":{"date-parts":[[2022,8,8]],"date-time":"2022-08-08T21:09:18Z","timestamp":1659992958000},"page":"1256","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Atmospheric Degradation of Two Hydrofluoroketones: Theoretical Rate Constants for the Gas-Phase OH-Oxidation of HFK-447mcc and HFK-465mc"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2312-990X","authenticated-orcid":false,"given":"Lu\u00eds Pedro","family":"Viegas","sequence":"first","affiliation":[{"name":"Coimbra Chemistry Centre-Institute of Molecular Sciences (CQC-IMS), Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"810","DOI":"10.1038\/249810a0","article-title":"Stratospheric Sink for Chlorofluoromethanes: Chlorine Atom-Catalysed Destruction of Ozone","volume":"249","author":"Molina","year":"1974","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"207","DOI":"10.1038\/315207a0","article-title":"Large Losses of Total Ozone in Antarctica Reveal Seasonal ClOx\/NOx Interaction","volume":"315","author":"Farman","year":"1985","journal-title":"Nature"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"(1993). 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