Experimental Studies of the State-to-State Chemical Dynamics of Reactions Involving Air Triatomics

The first measurements of the full vibrational distribution of NO produced in the room temperature reaction N(4S) + 02 yields NO (0 or = 7) + 0 are reported in this work. The technique of UV laser induced fluorescence detection of NO(v) was employed, which permitted observation of NO production under conditions where 02 vibrational quenching of the NO(v) was insignificant. The technique permitted the first observation of NO(v=0) and NO(v=1) concentrations. The relative ratios of (NO(v))/k sub D superscript v were measured, where k sub D superscript v is the vibrationally dependent rate of NO removal by the reaction N(4S) + NO(v) yields k sub D superscript v sub N 2 + 0. Assuming that k sub D superscript v is independent of v, we calculate that the NO vibrational distribution ratios for 0 or = 57.8: 4.2: 5.7: 6.9: 5.8: 6.5: 6.6: 6.5, expressed as % of total NO production. This result indicates that the N(4S) + 02 reaction produces 42% of the NO molecules in infrared-active states, 38% of them in levels or = 2. In terms of energy deposition, 29% of the 1.39 eV exothermicity of the reaction goes into v or = 1, 28% into v or = 2; this is approximately 3 times more than predicted by earlier studies. Prepared in cooperation with Aerospace Corp., El Segundo, CA. Ivan A. Getting Labs.