Structures in the energy dependence of the rate constant for ketene isomerization

Lovejoy, Edward R.; Moore, C. Bradley
May 1993
Journal of Chemical Physics;5/15/1993, Vol. 98 Issue 10, p7846
Academic Journal
The isomerization of highly vibrationally excited and rotationally cold ketene has been investigated by monitoring the 12CO and 13CO dissociation products following laser excitation of jet-cooled 12CH2 13CO, 13CH2 12CO, and 12CD2 13CO. The rate constants for the reactions 12CH2 13CO⇌13CH2 12CO and 12CD2 13CO⇌13CD2 12CO are reported as a function of energy with a resolution of 1 cm-1. The rate constants exhibit pronounced peaks as a function of energy near the reaction threshold. This structure is attributed to quasistable motion along the reaction coordinate in the vicinity of the isomerization transition state.


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