Elementary reactions of the NCl radical. Part 1.—Rate constants for the reactions NCl + NCl → N2+ 2Cl and O + NCl → NO + Cl

Abstract

A kinetics study of the NCl radical at 295 K has been carried out in a discharge–flow system using mass-spectrometric detection with molecular-beam sampling. NCl radicals were generated by the reaction of Cl atoms with N₃Cl: Cl + N₃Cl → N₃+ Cl₂, Cl + N₃→ NCl(b¹∑⁺), (a¹Δ), (X³∑^–)+ N₂.

Metastable excited-state (a¹Δ), (b¹∑⁺) NCl radicals were shown to react with Cl₂ to produce NCl₂ radicals: NCl*+ Cl₂→ NCl₂+ Cl. The rate constants (295 K) for the following reactions of ground-state (X³∑^–) NCl radicals have been measured: NCl + NCl → N₂+ 2Cl; k₂₉₅=(8.1 ± 1.8)× 10^–12 cm³ s^–1(2σ), O + NCl → NO + Cl; k₂₉₅=(1.2 ± 0.6)× 10^–10 cm³ s^–1(2σ).