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Journal of Atmospheric Chemistry

, Volume 8, Issue 1, pp 41–62 | Cite as

Ultraviolet absorption spectrum of trifluoro-bromo-methane, difluoro-dibromo-methane and difluoro-bromo-chloro-methane in the vapor phase

  • D. Gillotay
  • P. C. Simon
Article

Abstract

Ultraviolet absorption cross-sections of trifluoro-bromo-methane (CF3Br-Halon 1301), difluoro-dibromo-methane (CF2Br2-Halon 1202) and of difluoro-bromo-chloro-methane (CF2BrCl-Halon 1211) are measured in the wavelength interval 172–304 nm for temperatures ranging from 210 to 295 K with uncertainties of between 2 and 4%. They are compared with previous measurements available at room temperature. Temperature effects are discussed and parametrical formulae are proposed to compute the absorption cross-sections for wavelengths and temperatures useful in atmospheric modelling calculations. Photodissociation coefficients are presented and their temperature dependence is discussed.

Key words

Bromo-fluoro-methanes UV absorption cross-sections photodissociation coefficients temperature dependence 

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Copyright information

© Kluwer Academic Publishers 1989

Authors and Affiliations

  • D. Gillotay
    • 1
  • P. C. Simon
    • 1
  1. 1.Institut d'Aéronomie Spatiale de BelgiqueBrusselsBelgium

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