Kinetics of the N+NCO reaction at 298 K

Abstract

The rate constant for the reaction of NCO (X²Π) radicals with N(⁴S) atoms at room temperature has been determined to be (5.5±0.8)×10^-11 cm³ molecule^-1 s^-1 by direct measurement by laser-induced fluorescence. This result is 70% higher than a value estimated from shock tube data at 1700 K, and suggests that the reaction takes place over a largely attractive potential surface. When the result is combined with high temperature data, it suggests that the major products of the reaction areN₂+CO, but as these cannot be formed in their ground electronic states in a spin-allowed process, arguments are proposed for the formation of triplet state products. No IR emission could be assigned as originating from CO, and possible reasons for this are discussed.

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