EXPERIMENTAL AND THEORETICAL-STUDIES OF THE REACTION BETWEEN CF3 AND NO2 AT 298 K

The title reaction has been studied by pulse radiolysis combined with time-resolved infrared diode laser spectroscopy. The kinetics of CF3 w ere analysed taking into account the two competing reactions CF3 + CF3 M --> C2F6 + M (1) and CF3 + NO2 --> CF2O + FNO (2a). Based on studie s of the yield and kinetics of CF3 we determined values of the absorpt ion cross section, sigma(CF3) = (1.96 +/- 0.20) X 10(-17) cm(2) molecu le(-1) at 1263.567 cm(-1) and the bimolecular rate constant, k(1) = (1 .04 +/- 0.12) X 10(-11) cm(3) molecule(-1) s(-1) with a bath gas press ure of 20 mbar at 298 K. Reaction (2a) was studied under pseudo-first- order conditions and the value of k(2a) = (1.53 +/- 0.10) X 10(-11) cm (3) molecule(-1) s(-1) was found to be independent of bath gas pressur e in the range 4-22 mbar. Based on the characteristic absorption spect ra of the products, the branching ratio of reaction (2a) was found to be 0.95. (C) 1998 Elsevier Science B.V.