{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T12:31:00Z","timestamp":1786710660947,"version":"build-2736575974"},"reference-count":41,"publisher":"AIP Publishing","issue":"6","funder":[{"DOI":"10.13039\/501100006593","name":"Board of Research in Nuclear Sciences","doi-asserted-by":"publisher","award":["58\/14\/18\/2020"],"award-info":[{"award-number":["58\/14\/18\/2020"]}],"id":[{"id":"10.13039\/501100006593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001843","name":"Science and Engineering Research Board","doi-asserted-by":"publisher","award":["CRG\/2022\/005470"],"award-info":[{"award-number":["CRG\/2022\/005470"]}],"id":[{"id":"10.13039\/501100001843","id-type":"DOI","asserted-by":"publisher"}]},{"name":"DST-WISE","award":["CS-10\/2024"],"award-info":[{"award-number":["CS-10\/2024"]}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,8,14]]},"abstract":"<jats:p>Photolysis of 1-nitropropane, 2-methyl-2-nitropropane, and (nitromethyl)benzene at 213 and 225\u00a0nm reveals distinct mechanistic features in CH3 and NO elimination channels. The CH3 fragments exhibit anisotropic, non-statistical translational energy distributions, consistent with barrier-impulsive dissociation on the T1 surface occurring on femtosecond timescales with restrictive intramolecular vibrational redistribution (IVR). In contrast, NO fragments display bimodal translational energy distributions with large slow\/fast branching ratios, indicating preferential dissociation on the S0 surface following efficient IVR. Two-dimensional potential energy surface calculations along C\u2013N and C\u2013O coordinates show that NO2 roaming constitutes the minimum energy pathway on the T1 surface, while semi-tight transition states dominate on the S0 surface. Despite structural variation, \u03b1-substitution does not significantly alter the fundamental NO release mechanism; however, variations in triplet yield modulate the contribution of the fast component. Interestingly, the CH3 and NO release follow contrasting behavior in terms of IVR dynamics.<\/jats:p>","DOI":"10.1063\/5.0338909","type":"journal-article","created":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T11:33:52Z","timestamp":1786707232000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":0,"title":["Impact of \u03b1-substitution on the photodissociation dynamics of nitromethane: The CH3 and NO release channels"],"prefix":"10.1063","volume":"165","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-2959-710X","authenticated-orcid":false,"given":"Shaivi","family":"Kesari","sequence":"first","affiliation":[{"name":"Department of Chemistry, Indian Institute of Technology Bombay , Mumbai 400076,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7343-5951","authenticated-orcid":false,"given":"Monali","family":"Kawade","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Indian Institute of Technology Bombay , Mumbai 400076,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0811-7249","authenticated-orcid":false,"given":"G. 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