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The deuterium isotope effect in disproportionation of CF2D radicals

✍ Scribed by G. O. Pritchard; D. W. Follmer

Publisher: John Wiley and Sons
Year: 1973
Tongue: English
Weight: 160 KB
Volume: 5
Category: Article
ISSN: 0538-8066
DOI: 10.1002/kin.550050115

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✦ Synopsis

The disproportionation reactions of radicals, particularly of small alkyl radicals, continue to interest kineticists as evidenced by continuing recent investigations and interpretative discussions [ 1,. The most extensively investigated disproportionation-combination ratio is that for two ethyl radicals: through 1968 Trotman-Dickenson [5] lists about 35 determinations of kd/k, for the system. All of the most reliable data indicate a value of kd/k, lkom about 0.10 to 0.14. In agreement with this range of values, two very recent reports give kd/k, = 0.14, obtained via H atom addition to ethylene [3], and kd/k, = 0.1 1, obtained from (CH3CDz)zCO photolysis [ S ] . The latter value is the average of the six experiments reported. A slight trend with temperature was noted, as suggested by previous workers [7]. The ethene formed was exclusively CHz=CD2, so that any isotope effect is purely secondary. In 1960, in a study of the reactions of CZD, radicals, Boddy

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