An Experimental and Theoretical Study of the Reaction Between NH(X3Σ−) + SO(X3Σ−)

Abstract

Abstract The kinetics of the reaction between NH(X3Σ–) + SO(X3Σ–) have been studied over the range 295–703 K using pulsed laser photolysis / laser induced fluorescence in 100 Torr He. The rate coefficient is (5.0±2.0)×10−11 cm3 molecule−1 s−1, and is independent of temperature within experimental scatter. Electronic structure calculations show that reaction proceeds via bound intermediates to form NS + OH and NO + SH as the major bimolecular products. An RRKM / master equation analysis shows that stabilization of the intermediates is negligible at the pressures investigated (<104 Torr), so that the overall rate coefficient is independent of pressure. The calculations show that the main product channel under combustion conditions is NS + OH. Attempts to observe NS under the experimental conditions were unsuccessful. The experimental decay data are consistent with the occurrence of the reaction NH2 + Cl → NH + HCl at temperatures above 500 K; approximate Arrhenius parameters are provided.