Computational Studies of the Kinetics of the C + NO and O + CN Reactions

Thermal rate coefficients for the reactions C( 3 P) + NO(X 2 Π) → CN(X 2 Σ + ) + O( 3 P), C( 3 P) + NO(X 2 Π) → CO(X 1 Σ + ) + N( 2 D), and O( 3 P) + CN(X 2 Σ + ) → CO(X 1 Σ + ) + N( 2 D) in the temperature range from 5 to 5000 K have been obtained using quasiclassical trajectory calculations. Results are reported for two ab initio potential energy surfaces corresponding to states of 2 A ‘ and 2 A ‘ ‘ symmetry. Good agreement between calculated and experimental rate coefficients are obtained for the C + NO reactions for all temperatures, whereas the rate coefficient for the O + CN reaction at room temperature is larger than that found experimentally. The dynamics is considerably different on the two potential energy surfaces with the 2 A ‘ ‘ giving rate coefficients in better agreement with experiments. The quality of the potential energy surfaces are discussed in the light of new electronic structure calculations including spin−orbit coupling.