Absolute rate constant measurements for the radiative combination ofatomic oxygen with nitric oxide

摘要: The spectral radiant intensity and the absolute rate constant of NO-O chemiluminescent reaction have been determined over wavelength region 3875—20,000 A. A direct method calibration making use an NBS Standard light source was employed. In order to eliminate any possible interferences due wall effects, investigated in a freejet. distribution curve, which extended infrared up 20,000 A, independent pressures from 0.1 1 torr found be identical whether oxygen atoms were produced discharged O2 or N(4S) + NO( 27r) = N 2(1S) -f- O(3P). Additional measurements glow, performed hydrogen flame at 10 pressure indicated substantial shift maximum toward longer wave- lengths with increasing temperature. Four determinations observed range glow gave average value 6.8 X 10~17 cm3 molecule"1 sec"1 367°K probable error ±35%. HIS paper reports redetermination con- stant important reaction. It confirms earlier work that used different experimental tech- niques. importance NO-0 stems its as laboratory standard for chemiluminescence1 recent applications at- mospheric physics. For instance Golomb et al.,2 atomic concentration upper atmosphere by analyzing radiation chemiluminous nitric oxide trails deposited into rocket ex- periments. quantitative investigation chemiluminescence is also general interest connection interpretation observable phenomena occurring during missile re-entry gas phase flow around be- hind vehicle. first accurate determination this Fontijn Schiff.3 Prior their virtually no data available reactions accuracy greater than magni- tude. Schiff3 deter- mined quantum yield 3875-6200 chemical ac- tonometry. They solution 0.15 M-K3 Fe (0264)3 efficiency had accurately Hatchard Parker.4 final study Fontijn, Meyer, Schiff1 emission extend least 1.4 ju. On basis these actinometer (3875-14,000 A), calculated 6.4 10~ 17 molecule sec"1. present pre- mixed jet defined homogeneous zone reac- tion spectrometer large aper- ture. Absolute intensities comparison source.