Kinetics of the reactions of Cl(2P1/2) and Cl(2P3/2) atoms with C2H6, C2D6, CH3F, C2H5F, and CH3CF3 at 298 K

The title reactions were studied using laser flash photolysis in conjunction with laser-induced fluorescence techniques. Separate monitoring of the two spin-orbit states, Cl(P-2(1/2)) and Cl(P-2(3/2)), was used to measure the kinetics of the reactions of CI(P-2(3/2)) with C2H6, C2D6, CH3F, C2H5F, and CH3CF3, the reaction of Cl(P-2(1/2)) with C2H6, and the relaxation of Cl(P-2(1/2)) by collisions with C2H6, C2D6, CH3F, C2H5F, and CH3CF3. Measured reaction rate constants were (units of cm(3) molecule(-1) s(-1)): k(Cl(P-2(3/2)) + C2H6) = (5.85 +/- 0.55) x 10(-11) k(Cl(P-2(3/2)) + C2D6) = (1.87 +/- 0.12) x 10(-11), k(Cl(P-2(3/2)) + CH3F)= (2.7 +/- 0.2) x 10(-13), k(Cl(P-2(3/2)) + CH3CH2F) = (6.8 +/- 0.5) x 10(-12), and k(Cl(P-2(3/2)) + CH3CF3) < 1 x 10(-14) cm(3) molecule(-1) s(-1). Measured relaxation rate constants for deactivation of Cl(P-2(1/2)) to Cl(P-2(3/2)) via collisions with C2H6. C2D6, CH3F, C2H5F, CH3CF3, and CF4 were (1.22 +/- 0.09) x 10(-10), (2.4 +/- 0.2) x 10(-10), (6.3 +/- 0.5) x 10-(11), (1.9 +/- 0.2) x 10(-10) (2.0 +/- 0.2) x 10(-10), and (2.3 +/- 0.4) x 10(-11), respectively. Collisions of Cl(P-2(1/2)) With C2H6 and C2D6 resulted mainly in the relaxation of Cl(P-2(1/2)) to Cl(P-2(3/2)) and not in the reactive formation of HCl (DCl). The rate constant of the reactive path for Cl(P-2(1/2)) + C2H6 was < 3 x 10(-11) cm(3) molecule(-1) s(-1).