Rate constant for the reaction NH2+ NO from 216 to 480 K

Abstract

The absolute rate constant for the reaction NH₂+ NO → products, has been measured at five temperatures from 216 to 480 K by the technique of combined flash-photolysis and laser-induced fluorescence (FP–LIF). NH₂ radicals were produced by the flash photolysis of ammonia and the fluorescent NH₂ photons were measured by multiscaling techniques. At each temperature the results were independent of variations in [NO], total pressure and flash intensity (i.e. initial [NH₂]). The results are best represented by the expression k=(2.77 ± 0.89)× 10^–7T^{–1.67 ± 0.05} cm³ molecule^–1 s^–1, where the error quoted is one standard deviation. The results are compared with previous determinations using the techniques of mass spectrometry, absorption spectroscopy, laser absorption spectroscopy and laser-induced fluorescence. The implications of the results are discussed with regard to combustion, post combustion and atmospheric chemistry. The results are also discussed theoretically.