Determination of the rate constants of the reactions of N3 and NCl free radicals using a simulation technique

A numerical integration method was used to solve the mathematical system corresponding to the mechanism of the reaction of Cl atoms with chlorine azide, N 3 Cl. The identification of calculated kinetic curves of the species involved in the mechanism with the experimental curves led to the determination of rate constants of the following secondary reactions: (2) Cl + N 3 → NCl + N 2 (3) N 3 + N 3 → 3N 2 (4) NCl + NCl → N 2 + Cl 2 At 298K, the rate constants were found to be k 2 : 0.75 – 1.5 × 10 −11 , k 3 : 5 – 8 × 10 −11 , and k 4 : 0.5 – 1 × 10 −11 (units are cm 3 molecule −1 sec −1 ).