T. Gierczak et al., RATE COEFFICIENTS FOR THE REACTIONS OF HYDROXYL RADICALS WITH METHANEAND DEUTERATED METHANES, The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory, 101(17), 1997, pp. 3125-3134
The rate coefficients for the reaction of OH with CH3D (k(1)), CH2D2 (
k(2)), CHD3 (k(3)), CD4 (k(4)), and CH4 (k(5)) as well as that of OD w
ith CH4 (k(6)) have been measured using the pulsed photolytic producti
on of OH followed by its detection via pulsed laser induced fluorescen
ce. k(1)-k(4) and k(6) were measured between similar to 220 and simila
r to 415 K, while k(5) was measured down to 195 K. The measured rate c
oefficients do not strictly obey the Arrhenius expression. However, be
low 298 K, they can be represented by the expressions (in cm(3) molecu
le(-1) s(-1)): k(1) = (3.11 +/- 0.44) x 10-(12) exp[-(1910 +/- 70)/T];
k(2) = (2.3 +/- 1.2) x 10(-12) exp[-(1930 +/- 250)/T]; k(3) = (1.46 /- 0.22) x 10(-12) exp[-(1970 +/- 70)/T]; k(4) = (1.00 +/- 0.22) x 10(
-12) exp[-(2100 +/- 120)/T]; k(5) = (1.88 +/- 0.11) x 10(-12) exp[-(16
95 +/- 30)/T]; k(6) = (1.68 +/- 0.12) x 10(-12) exp[-(1640 +/- 40)/T].
The obtained values of the rate coefficients and kinetic isotope effe
cts are compared with values previously measured or calculated by othe
r groups. The atmospheric implications of this data are briefly discus
sed.