Absolute rate constant for the O + NO chemiluminescence in the near infrared

Abstract

Infrared chemiluminescence from the process O + NO (+ M) → NO₂ + h ν (+ M) has been studied between 1.3 and 4.1 μm. The wavelength dependence of the continuum between 1.3 and 3.3 μm is in fair agreement with previous studies and the measured radiative rate constant at 1.51 μm, $I_{\text{1.51}}^0{\mathrm{=\; I}}_{\text{1.51}}\mathrm{/\; [}\mathrm{O}\mathrm{][}\mathrm{NO}]$ , of (2.4 ± 0.8) × 10⁻¹⁷ cm³ sec⁻¹ · μm⁻¹ establishes the NO–O glow in this spectral range as a secondary emission standard. Comparison with previous studies of the visible region of the glow implies that the over‐all radiative rate constant I^o lies in the range (9.4–11.2) × 10⁻¹⁷ cm³ sec⁻¹. In the region 3.3–4.1 μm, the previously observed broad band, peaking at 3.7 μm, shows a complex kinetic dependence on [O] and [M].