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.
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Gillotay, D., Simon, P.C. Ultraviolet absorption spectrum of trifluoro-bromo-methane, difluoro-dibromo-methane and difluoro-bromo-chloro-methane in the vapor phase. J Atmos Chem 8, 41–62 (1989). https://doi.org/10.1007/BF00053815
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DOI: https://doi.org/10.1007/BF00053815