Positionally dependent 15N fractionation factors in the UV photolysis of N2O determined by high resolution FTIR spectroscopy

Positionally dependent fractionation factors for the photolysis of isotopomers of N2O in natural abundance have been determined by high resolution FTIR spectroscopy at three photolysis wavelengths. Fractionation factors show clear 15N position and photolysis wavelength dependence and are in qualitative agreement with theoretical models but are twice as large. The fractionation factors increase with photolysis wavelength from 193 to 211 nm, with the fractionation factors at 207.6 nm for 14N15N16O, 15N14N16O and 14N14N18O equal to −66.5±5‰,−27.1±6‰ and −49±10‰, respectively.