Ultraviolet photodissociation of the HCCO radical studied by fast radical beam photofragment translational spectroscopy

Mordaunt, David H.; Osborn, David L.; Choi, Hyeon; Bise, Ryan T.; Neumark, Daniel M.
October 1996
Journal of Chemical Physics;10/8/1996, Vol. 105 Issue 14, p6078
Academic Journal
The ultraviolet photolysis of jet-cooled mass-selected ketenyl radicals has been investigated using the technique of fast radical beam photofragment translational spectroscopy. The C2Π(2A″)–X2A″ photofragment yield cross section spans 33 400–48 000 cm-1 and exhibits resolved resonances and broad continua. Dissociation produces both ground and excited state CH radicals in association with ground state CO fragments; there is no evidence for H atom elimination. Analysis of the photofragment kinetic energy release spectra yield a value for the C–C bond dissociation energy and heat of formation of HCCO: D0(HC–CO)=3.14±0.03 eV (72.4±0.7 kcal/mol) and ΔHf,00(HCCO)=1.82±0.03 eV (42.0±0.7 kcal/mol). © 1996 American Institute of Physics.


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