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Title: Three-isotope plot of fractionation in photolysis: A perturbation theoretical expression

Abstract

The slope of the three-isotope plot for the isotopomer fractionation by direct or nearly direct photodissociation is obtained using a perturbation theoretical analysis. This result, correct to first order in the mass difference, is the same as that for equilibrium chemical exchange reactions, a similarity unexpected a priori. A comparison is made with computational results for N{sub 2}O photodissociation. This theoretical slope for mass-dependent photolytic fractionation can be used to analyze the data for isotopic anomalies in spin-allowed photodissociation reactions. Earlier work on chemical equilibria is extended by avoiding a high-temperature approximation.

Authors:
;  [1]
  1. Noyes Laboratory of Chemical Physics MC 127-72, California Institute of Technology, Pasadena, California 91125 (United States)
Publication Date:
OSTI Identifier:
20723192
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 123; Journal Issue: 17; Other Information: DOI: 10.1063/1.2102908; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; EQUILIBRIUM; FRACTIONATION; ISOTOPE EFFECTS; ISOTOPES; MASS DIFFERENCE; NITROUS OXIDE; PERTURBATION THEORY; PHOTOLYSIS; REACTION KINETICS; SPIN

Citation Formats

Prakash, M.K., and Marcus, R.A. Three-isotope plot of fractionation in photolysis: A perturbation theoretical expression. United States: N. p., 2005. Web. doi:10.1063/1.2102908.
Prakash, M.K., & Marcus, R.A. Three-isotope plot of fractionation in photolysis: A perturbation theoretical expression. United States. doi:10.1063/1.2102908.
Prakash, M.K., and Marcus, R.A. Tue . "Three-isotope plot of fractionation in photolysis: A perturbation theoretical expression". United States. doi:10.1063/1.2102908.
@article{osti_20723192,
title = {Three-isotope plot of fractionation in photolysis: A perturbation theoretical expression},
author = {Prakash, M.K. and Marcus, R.A.},
abstractNote = {The slope of the three-isotope plot for the isotopomer fractionation by direct or nearly direct photodissociation is obtained using a perturbation theoretical analysis. This result, correct to first order in the mass difference, is the same as that for equilibrium chemical exchange reactions, a similarity unexpected a priori. A comparison is made with computational results for N{sub 2}O photodissociation. This theoretical slope for mass-dependent photolytic fractionation can be used to analyze the data for isotopic anomalies in spin-allowed photodissociation reactions. Earlier work on chemical equilibria is extended by avoiding a high-temperature approximation.},
doi = {10.1063/1.2102908},
journal = {Journal of Chemical Physics},
number = 17,
volume = 123,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 2005},
month = {Tue Nov 01 00:00:00 EST 2005}
}
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