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Title: Nitrogen isotopic fractionations in the low temperature (80 K) vacuum ultraviolet photodissociation of N 2

N 2 is a diatomic molecule with complex electronic structure. Interstate crossings are prominent in the high energy domain, introducing significant perturbations to the system. Nitrogen mainly photodissociates in the vacuum ultraviolet (VUV) region of the electromagnetic spectrum through both direct and indirect predissociation. Due to the complexity introduced by these perturbations, the nitrogen isotopic fractionation in N 2 photodissociation is extremely hard to calculate, and an experimental approach is required. We present new data of N-isotopic fractionation in N 2 photodissociation at low temperature (80 K), which shows a distinctly different15N enrichment profile compared to that at relatively higher temperatures (200 and 300 K). The new data, important to understanding the N-isotopic compositions measured in meteorites and other planetary bodies, are discussed in light of the knowledge of N 2 photochemistry and calculated photoabsorption cross sections in the VUV.
 [1] ;  [1] ;  [2] ;  [2] ;  [1]
  1. Univ. of California, San Diego, CA (United States). Dept. of Chemistry and Biochemistry
  2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Publication Date:
Grant/Contract Number:
Published Article
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 145; Journal Issue: 11; Related Information: © 2016 Author(s).; Journal ID: ISSN 0021-9606
American Institute of Physics (AIP)
Research Org:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Chemical Sciences, Geosciences & Biosciences Division; National Aeronautic and Space Administration (NASA)
Country of Publication:
United States
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 79 ASTRONOMY AND ASTROPHYSICS; photochemistry; vacuum chambers; temperature measurement; photons; photodissociation; predissociation; dissociation; meteorites; ultraviolet light; wave functions
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1420486; OSTI ID: 1459373