HR: 1340h
AN: B43A-0888 INVITED    [Abstracts]
TI: An absolute calibration of the site preference of 15N isotopic fractionation in N2O using FTIR spectroscopy
AU: * Griffith, D W
EM: griffith@uow.edu.au
AF: University of Wollongong, Centre for Atmospheric Chemistry, Wollongong, NSW 2522, Australia
AU: Parkes, S D
EM: sdp05@uow.edu.au
AF: University of Wollongong, Centre for Atmospheric Chemistry, Wollongong, NSW 2522, Australia
AU: Wilson, S R
EM: swilson@uow.edu.au
AF: University of Wollongong, Centre for Atmospheric Chemistry, Wollongong, NSW 2522, Australia
AU: Murphy, C
EM: clarem@uow.edu.au
AF: University of Wollongong, Centre for Atmospheric Chemistry, Wollongong, NSW 2522, Australia
AU: Haverd, V
AF: CSIRO Marine and Atmospheric Research, GPO Box 1666, Canberra, ACT 2601, Australia
AB: The bulk isotopic fractionation of ¹⁵N in nitrous oxide (N₂O) provides a valuable diagnostic for the pathways by which N₂O is formed and processed in the natural environment. As the two N atoms in N₂O are chemically inequivalent and do not exchange, ¹⁵N fractionation can be different at the two different sites. The preference for ¹⁵N fractionation between the two sites provides a further valuable diagnostic for N₂O processing, but its exploitation has been limited in part due to a lack of agreement in defining an absolute calibration of the site preference. Here we present an independent method for an absolute calibration of the ¹⁵N site preference based on high resolution FTIR spectroscopy of N₂O. IR spectroscopy naturally distinguishes the two isotopomers as separate species, provides absolute calibrations for both isotopomers independently, and is completely independent of mass spectrometric measurements.
DE: 0452 Instruments and techniques
DE: 0454 Isotopic composition and chemistry (1041, 4870)
DE: 0469 Nitrogen cycling
DE: 0490 Trace gases
SC: Biogeosciences [B]
MN: 2007 Fall Meeting