A reinvestigation of the near-ultraviolet photodissociation dynamics of the methyl radical

✍ Scribed by Steven H.S. Wilson; Jonathan D. Howe; Keith N. Rosser; Michael N.R. Ashfold; Richard N. Dixon

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 422 KB
• Volume: 227
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(94)00859-0

✦ Synopsis

The translational energy spectrum of H Rydberg atoms resulting from the photolysis of the methyl radical ( CH3) at 2 16.3 nm has been recorded. The use of pulsed supersonic jet flash pyrolysis of azomethane (CH3N2CHa) as a clean source of methyl radicals has allowed a clear analysis of the data, eliminating possible interference from other molecular species. The measured times-of-flight of the resulting H atoms indicate that the partner CHr fragments resulting from predissociation of CHs (8) radicals are formed in their low-lying H 'A, excited state, as predicted by theory. An earlier contradictory report of this dissociation process, using methanethiol ( CHsSH) as a photolytic precursor to generate methyl radicals, has been reinterpreted in terms of secondary dissociation of ground-state thiomethoxy radicals (CHrS) yielding electronically excited thioformaldehyde CH,S(A'A,)+H(*S).