scholarly journals Kinetics of the Reactions of Ozone with Halogen Atoms in the Stratosphere

Atmosphere ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1053
Author(s):  
S. Vijayakumar ◽  
Duminda S. Ranasinghe ◽  
David M. Wilmouth

It is well established that reaction cycles involving inorganic halogens contribute to the depletion of ozone in the atmosphere. Here, the kinetics of O3 with halogen atoms (Cl, Br, and I) were investigated between 180 and 400 K, expanding the temperature range relative to prior studies. Canonical variational transition state theory including small curvature tunneling correction (CVT/SCT) were considered, following the construction of the potential energy surfaces. MRCI + Q/aug-ano-pVTZ//MP2/aug-cc-pV(T + d)Z and MRCI + Q/aug-ano-RCC-VTZP//MP2/aug-cc-pV(T + d)Z levels of theory were used to calculate the kinetic parameters. Calculated rate coefficients were used to fit the Arrhenius equations, which are obtained to be k1 = (3.48 ± 0.4) × 10−11 exp[(−301 ± 64)/T] cm3 molecule−1 s−1, k2 = (3.54 ± 0.2) × 10−11 exp[(−990 ± 35)/T] cm3 molecule−1 s−1 and k3 = (1.47 ± 0.1) × 10−11 exp[(−720 ± 42)/T] cm3 molecule−1 s−1 for the reactions of O3 with Cl, Br, and I atoms, respectively. The obtained rate coefficients for the reactions of O3 with halogen atoms using CVT/SCT are compared to the latest recommended rate coefficients by the NASA/JPL and IUPAC evaluations. The reactivity trends and pathways of these reactions are discussed.

2006 ◽  
Vol 125 (6) ◽  
pp. 064312 ◽  
Author(s):  
A. J. C. Varandas ◽  
P. J. S. B. Caridade ◽  
J. Z. H. Zhang ◽  
Q. Cui ◽  
K. L. Han

2015 ◽  
Vol 17 (5) ◽  
pp. 3142-3156 ◽  
Author(s):  
Manas Ranjan Dash ◽  
B. Rajakumar

Rate coefficients for the reactions of C2H radicals with methane (k1), ethane (k2), propane (k3), ethylene (k4), and propylene (k5) were computed using canonical variational transition state theory (CVT) coupled with hybrid-meta density functional theory (DFT) over a wide range of temperatures from 150 to 5000 K.


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