A MASS-SPECTROMETRIC STUDY OF THE NH2+NO2 REACTION

The total rate constant and product branching ratios of the NH2 + NO2 reaction have been determined in the temperature range of 300-910 K us ing a pulsed laser photolysis/mass spectrometric technique by probing H2O and N2O product formation and NO2 reactant decay. A weighted least -squares fit of our result for the total rate constant yields the foll owing expression: k(1) = (8.1 +/- 0.33) x 10(16) T-1.44 exp(-135/T) cm (3)/(mol . s). The product branching ratio for the N2O + H2O channel o f the NH2 + NO2 reaction obtained by modeling the absolute N2O product yield near or at its plateau value gives 0.19 +/- 0.02 without signif icant temperature dependence, confirming our earlier result obtained b y using a high-gain amplifier with no time-resolved information (ref 1 8).