✦ LIBER ✦

Kinetic and thermochemical parameters of chlorine atom transfer reactions from CF3Cl, CF3CF2Cl, CF2ClCF2Cl, and CF2ClCFCl2 in gas phase

✍ Scribed by R. A. Taccone; O. Salinovich; E. H. Staricco

Publisher: John Wiley and Sons
Year: 1989
Tongue: English
Weight: 568 KB
Volume: 21
Category: Article
ISSN: 0538-8066
DOI: 10.1002/kin.550210504

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✦ Synopsis

The following reactions:

(1, -1)

. CF, + CzFSC1 CF&l + ' CzF5

(2)

(3)

were studied over the temperature ranges 533-687 K, 563-663 K, and 503-613 K for the forward reactions respectively and over 683-763 K, for the back reaction. Arrhenius parameters for chlorine atom transfer were determined relative to the combination of the attacking radicals. The AH,Xl) = -3.95 2 0.45 kcal mol-' was calculated and from this value the AHP(CzF,Cl) = -2.66.3 f 2.5 kcal mol-' and D(CzF5-C1) = 82.0 ? 1.2 kcal mol-' were obtained. Besides, the AH321 was estimated leading to D(CFzCICFzC1) = 79.2 It 5 Kcal mol-'. The bond dissociation energies and the heat of formation are compared with those of the literature. The effect of the halogen substitutents as well as the importance of the polar effects for halogen transfer processes are discussed.

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