Rate parameters for reaction of oxygen atoms with C2F4, CF2CFCl and CF2CCl2
作者:W. J. R. Tyerman
DOI:10.1039/tf9696500163
日期:——
Ground-state CF2 was monitored by kinetic spectroscopy after long wavelength flash photolysis of C2F4+ NO2+ N2 mixtures and was ascribed as a product of the overall reaction O(23P)+ C2F4→ CF2O + CF2. (1) From the decrease in the CF2 yield in competitive systems, rate constants relative to k1 were determined for CF2CFCl and CF2CCl2. The reactivities of the chlorofluoroethylenes show a similar trend with ionization potential to that established for hydrocarbon olefins. From preliminary measurements of the overall decomposition of C2F4 flashed in O2 at 25°C, it is proposed that singlet CF2 reacts with O2 about 0.2 times as rapidly as with C2F4. Although there was no direct evidence for triplet CF2 molecules formed in (1), the results are consistent with an earlier analysis of continuous photolysis experiments, if CF*2 is rapidly relaxed in collisions with NO2 or NO.
Heicklen, J.; Cohen, N.; Saunders, D., Journal of Physical Chemistry, 1965, vol. 69, p. 1774 - 1775
作者:Heicklen, J.、Cohen, N.、Saunders, D.
DOI:——
日期:——
Fate of Triplet Difluoromethylene
作者:Timothy Johnston、Julian Heicklen
DOI:10.1063/1.1711919
日期:1967.7.15
Triplet CF2 was produced by the reaction of ground-state oxygen atoms with C2F4 at room temperature. This radical can react with O2 or undergo self-annihilation to form singlet CF2: CF23+O2→CF2O2;2CF23→C2F4*→2CF21,where the superscripts 1 and 3 refer to singlet and triplet. The ratio ke/kf1/2 was estimated to be about 12 (liter/mole·sec)1/2.
Russo, Antonio; DesMarteau, Darryl D., Angewandte Chemie, 1993, vol. 105, # 6, p. 956 - 958