formation kinetics of H2CO support the observations of
Gutman and co-workers4,5 that the main products for the
vinyl radical reaction with molecular oxygen at low pressures
are HCO and H2CO.
For the vinyl radical reaction with molecular chlorine the
only reaction product identified was C2H3Cl, which ion signal
rise in Fig. 3 properly reflects the decay of the vinyl radical
within 1s uncertainty, when the vinyl radical heterogenous loss
is taken into account as above. This confirms the previously
proposed18 main reaction channel, C2H3 + Cl2 ! C2H3Cl + Cl,
(DHꢄ ¼ ꢂ158 kJ molꢂ1 20).
References
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Acknowledgements
We are greatly thankful to our laboratory technicians, espe-
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financial support in the construction of the apparatus and
research work to: Research Council for Biosciences and
Environment of Academy of Finland and Maj and Torr
Nessling Foundation. A.J.E. also thanks the Jenny and
Antti Wihuri Foundation and Kone Foundation for their
research grants.
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Phys. Chem. Chem. Phys., 2003, 5, 2557–2561
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