On molecular origin of mass-independent fractionation of oxygen isotopes in the ozone forming recombination reaction

Proc Natl Acad Sci U S A. 2013 Oct 29;110(44):17708-13. doi: 10.1073/pnas.1215464110. Epub 2013 Feb 19.

Abstract

Theoretical treatment of ozone forming reaction is developed within the framework of mixed quantum/classical dynamics. Formation and stabilization steps of the energy transfer mechanism are both studied, which allows simultaneous capture of the delta zero-point energy effect and η-effect and identification of the molecular level origin of mass-independent isotope fractionation. The central role belongs to scattering resonances; dependence of their lifetimes on rotational excitation, asymmetry; and connection of their vibrational wave functions to two different reaction channels. Calculations, performed within the dimensionally reduced model of ozone, are in semiquantitative agreement with experiment.

Keywords: collisional energy transfer; isotope effect; quantum resonance; recombination rate constant; width of resonant states.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Atmosphere / analysis*
  • Kinetics
  • Models, Chemical*
  • Oxygen Isotopes / chemistry*
  • Ozone / chemical synthesis*

Substances

  • Oxygen Isotopes
  • Ozone