Positionally dependent <supscr>15</supscr>N fractionation factors in the UV photolysis of N<subscr>2</subscr>O determined by high resolution FTIR spectroscopy

Positionally dependent fractionation factors for the photolysis of isotopomers of N20 in natural abundance have been determined by high resolution FTIR spectroscopy at three photolysis wavelengths. Fractionation factors show clear lSN 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 14N15N160, 15N14N160 and 14N14N180 equal to -66.5 + 5 %0, -27.1 + 6 %0 and -49 + 10 %0, respectively.