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


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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  1. Berg, W. W., Heidt, L. E., Pollock, W., Sperry, P. D., Cicerone, R. J., and Gladney, E. S., 1984, Brominated organic species in the Arctic atmosphere, Geophys. Res. Lett. 11, 429–432.Google Scholar
  2. Brasseur, G. and Simon, P. C., 1981, Stratospheric and thermal response to long-term variability in solar UV irradiance, J. Geophys. Res. 86, 7343–7362.Google Scholar
  3. Brasseur, G. and Simon, P. C., 1988, Changes in stratospheric ozone: observations and theories, Aeronomica Acta A334.Google Scholar
  4. Class, Th., Kohnle, R., Ballschmiter, K., 1986, Chemistry of organic races in air VII: Bromo- and bromochloromethanes in air over Atlantic Ocea, Chemosphere 15, 429–436.Google Scholar
  5. Cicerone, R. J., Heidt, L. E., and Pollock, W. H., 1988, Measurements of atmospheric methyl bromide (CH3Br) and bromoform (CHBr3), J. Geophys. Res. 93, 3745–3749.Google Scholar
  6. Fabian, P., Borchers, R., Penkett, S. A., and Prosser, N. J. D., 1981, Halocarbons in the stratosphere, Nature 294, 733–735.Google Scholar
  7. Gillotay, D. and Simon, P. C., 1988, Ultraviolet absorption cross-sections of methyl bromide at stratospheric temperatures, Ann. Geophysicae 6, 211–215.Google Scholar
  8. Kockarts, G., 1976, Absorption and photodissociation in the Schumann-Runge bands of molecular oxygen in the terrestrial atmosphere, Planet. Space Sci. 24, 589–604.Google Scholar
  9. Lal, S., Borchers, R., Fabian, P., and Kruger, B. C., 1985, Increasing abundance of CBrClF2 in the atmosphere, Nature 316, 135–136.Google Scholar
  10. Molina, L. T., Molina, M. J., and Rowland, F. S., 1982, Ultraviolet absorption cross-sections of several brominated methanes and ethanes of atmospheric interest, J. Phys. Chem. 86, 2672–2676.Google Scholar
  11. Nicolet, M., 1984, On the molecular scattering in the terrestrial atmosphere: an empirical formula for calculation in the homosphere, Planet. Space Sci. 32, 1467–1468.Google Scholar
  12. Penkett, S. A., Jones, B. M. R., Rycroft, M. J., and Simmons, D. A., 1985, An interhemispheric comparison of the concentrations of bromide compounds in the atmosphere, Nature 318, 550–553.Google Scholar
  13. Prather, M. J., McElroy, M. B., and Wofsy, S. C., 1984, Reductions in ozone at high concentrations of stratospheric halogens, Nature 312, 227–231.Google Scholar
  14. Rodriguez, J. M., Ko, M. K. M., and Sze, N. D., 1986, Chlorine chemistry in the Antarctic stratosphere: Impact of OCIO and Cl2O2 and implications for observations, Geophys. Res. Lett. 13, 1292–1295.Google Scholar
  15. Simon, P. C., Gillotay, D., Vanlaethem-Meuree, N., and Wisemberg, J., 1988, Ultraviolet absorption cross-sections of chloro- and chlorofluoro-methanes at stratospheric temperatures, J. Atmos. Chem. 7, 107–135.Google Scholar
  16. WMO, 1985, Atmospheric Ozone 1985, WMO global ozone research and monitoring project, Report 16, vol. I, pp. 355–367.Google Scholar
  17. Yung, Y. L., Pinto, J. P., Watson, R. T., and Sander, S. P., 1980, Atmospheric bromine and ozone perturbations in the lower stratosphere, J. Atmos. Sci. 37, 339–353.Google Scholar

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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