Massive isotopic effect in vacuum UV photodissociation of N2 and implications for meteorite data
Abstract
In this paper, we account for the wide range (approximately a few thousand permil) of nitrogen isotopic composition measured in solar system materials. Several theoretical models have been proposed to explain the nitrogen isotopic enrichments measured in meteorites (especially in organic matter) and in cometary ice (NH3 and/or HCN). These models include ion-molecular isotope exchange reactions and isotope self-shielding in the disk. However, a major limit is that there are no experiments to substantiate any model. We measured and found massive N-isotopic fractionations during vacuum UV photodissociation of N2, perhaps one of the largest isotope effects ever measured, and present mechanistic evidence for the wide distribution in nitrogen isotopic compositions.
- Publication:
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Proceedings of the National Academy of Science
- Pub Date:
- October 2014
- DOI:
- Bibcode:
- 2014PNAS..11114704C