Fractionation of 14 N 15 N 16 O and 15 N 14 N 16 O During Photolysis at 213 nm
نویسندگان
چکیده
Motivated by Yung and Miller’s suggestion [1997] that N2O is isotopically fractionated during UV photolysis in the stratosphere, we have studied the photolysis rates of the NNO and NNO structural isotopomers. In this study, we follow the concentrations of these compounds with FTIR spectroscopy during photolysis at 213 nm. Our results show that, as Yung and Miller predicted, the photolysis rate of NNO is faster than NNO at this wavelength. When fitted to a Rayleigh fractionation model, the observations yield single-stage enrichment factors of ε(NNO / NNO) = -73 ± 5 per mil and ε(NNO / NNO) = -41 ± 10 per mil. Comparisons are provided with theoretical calculation and previous measurements.
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