A theoretical and experimental study of the CN + NO association reaction

A pulsed-laser photolysis/laser-induced fluorescence technique is employed in the determination of the pressure and temperature dependence of the reaction of CN with NO in the range from 207 to 740 K and for Ar bath gas pressures ranging from 30 to 900 Torr. A variational RRKM model coupled with a one-dimensional master equation treatment provides a reasonably satisfactory description of the available kinetic data for both the association and dissociation processes. The association kinetic data is best fit by a collisional energy transfer parameter, 〈ΔE〈_d0wn, for the simple exponential down model, which gradually increases from -35 cm^-1 at 100 K to -500 cm^-1 at 740 K. The expression 3.4 x 10^-10 exp(120/T) cm³ s^-1 reproduces the present theoretical estimates for the high-pressure rate constant in the range from 207 to 740 K.