Direct detection of polyynes formation from the reaction of ethynyl radical (C2H) with propyne (CH3–C
CH) and allene (CH2
C
CH2)
Abstract
The reactions of the ethynyl radical (C2H) with C–C
C–H) and 50–30% C5H4, with a C5H4-isomer distribution of 15–20%
C
CH–C
CH) and 85–80% methyldiacetylene (CH3–C
C–C
CH). The reaction of
C–CH2–C
CH). Diacetylene is most likely not produced by this reaction; an upper limit of 30% on the branching fraction to diacetylene can be derived from the present experiment. The mechanisms of polyynes formation by these reactions as well as the implications for Titan’s atmospheric chemistry are discussed.