TY - JOUR
T1 - Investigation of Product Formation in the O(1D, 3P) + N2O Reactions
T2 - Comparison of Experimental and Theoretical Kinetics
AU - Pham, Tien V.
AU - Lin, M. C.
N1 - Publisher Copyright:
© 2022 American Chemical Society. All rights reserved.
PY - 2022/2/24
Y1 - 2022/2/24
N2 - The spin-forbidden and spin-allowed reactions of the excited and ground electronic state O(1D, 3P) + N2O(X1ς+) systems have been studied theoretically. Quantum calculations at the UCCSD(T)/CBS(T, Q, 5)//CCSD/aug-cc-pVTZ level have located two crossing points, MSX1 and MSX2, with energies of 11.2 and 22.7 kcal mol-1above O(3P) + N2O, respectively. The second-order P-independent rate constants for the adiabatic and non-adiabatic thermal reactions predicted by adiabatic TST/VTST and non-adiabatic TST, respectively, agree closely with the available literature results. The second-order rate constant, k2a= 9.55 × 10-11exp(-26.09 kcal mol-1/RT) cm3molecule-1s-1, for the O(3P) + N2O → 2NO reaction, contributed by both the dominant MSX2 and the minor TS1-a channels, is in reasonable accord with prior experiments and recommendations, covering the temperature range of 1200-4100 K. The calculated rate constant, k2b= 4.47 × 10-12exp(-12.9 kcal mol-1/RT) cm3molecule-1s-1, for the O(3P) + N2O → N2+ O2(a1Δg) reaction, occurring exclusively via MSX1, is also in good agreement with the combined experimental data measured in a shock tube study at T = 1940-3340 K (ref 16) and the result measured by Fourier transform infrared spectroscopy in the temperature range of 988-1083 K (ref 17). Moreover, the spin-allowed rate constants predicted for the singlet-state reactions, k1a= (7.06-7.46) × 10-11cm3molecule-1s-1for O(1D) + N2O → 2NO and k1b= (4.36-4.66) × 10-11cm3molecule-1s-1for O(1D) + N2O → N2+ O2(a1Δg) in the temperature range of 200-350 K, agree quantitatively with the experimentally measured data, while the total rate constant k1= k1a+ k1bwas also found to be in excellent accordance with many reported values.
AB - The spin-forbidden and spin-allowed reactions of the excited and ground electronic state O(1D, 3P) + N2O(X1ς+) systems have been studied theoretically. Quantum calculations at the UCCSD(T)/CBS(T, Q, 5)//CCSD/aug-cc-pVTZ level have located two crossing points, MSX1 and MSX2, with energies of 11.2 and 22.7 kcal mol-1above O(3P) + N2O, respectively. The second-order P-independent rate constants for the adiabatic and non-adiabatic thermal reactions predicted by adiabatic TST/VTST and non-adiabatic TST, respectively, agree closely with the available literature results. The second-order rate constant, k2a= 9.55 × 10-11exp(-26.09 kcal mol-1/RT) cm3molecule-1s-1, for the O(3P) + N2O → 2NO reaction, contributed by both the dominant MSX2 and the minor TS1-a channels, is in reasonable accord with prior experiments and recommendations, covering the temperature range of 1200-4100 K. The calculated rate constant, k2b= 4.47 × 10-12exp(-12.9 kcal mol-1/RT) cm3molecule-1s-1, for the O(3P) + N2O → N2+ O2(a1Δg) reaction, occurring exclusively via MSX1, is also in good agreement with the combined experimental data measured in a shock tube study at T = 1940-3340 K (ref 16) and the result measured by Fourier transform infrared spectroscopy in the temperature range of 988-1083 K (ref 17). Moreover, the spin-allowed rate constants predicted for the singlet-state reactions, k1a= (7.06-7.46) × 10-11cm3molecule-1s-1for O(1D) + N2O → 2NO and k1b= (4.36-4.66) × 10-11cm3molecule-1s-1for O(1D) + N2O → N2+ O2(a1Δg) in the temperature range of 200-350 K, agree quantitatively with the experimentally measured data, while the total rate constant k1= k1a+ k1bwas also found to be in excellent accordance with many reported values.
UR - http://www.scopus.com/inward/record.url?scp=85125112397&partnerID=8YFLogxK
U2 - 10.1021/acs.jpca.1c09477
DO - 10.1021/acs.jpca.1c09477
M3 - Article
C2 - 35156819
AN - SCOPUS:85125112397
SN - 1089-5639
VL - 126
SP - 1103
EP - 1113
JO - Journal of Physical Chemistry A
JF - Journal of Physical Chemistry A
IS - 7
ER -