Kinetic investigation of the gas phase atomic sulfur and nitrogen dioxide reaction

The kinetics of the reaction of atomic sulfur and nitrogen dioxide have been investigated over the temperature range 298 to 650 K and pressures from 14--405 mbar using the laser flash photolysis - resonance fluorescence technique. The overall bimolecular rate expression k (T) = (1.88 +/- 0.49) x10-11 exp-(4.14 +/- 0.10 kJ mol-1)/RT cm3 molecule -1 s-1 is derived.;Ab initio calculations were performed at the CCSD(T)/CBS level of theory and a potential energy surface has been derived. RRKM theory calculations were performed on the system. It is found that an initially formed SNO 2 is vibrationally excited and the rate of collisional stabilization is slower than the rate of dissociation to SO + NO products by a factor of 100--1000, under the experimental conditions.