ISSN:
1573-0662
Keywords:
Chloromethanes
;
chlorofluoromethanes
;
ultraviolet absorption
;
photodissociation coefficients
;
temperature dependence
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Geosciences
Notes:
Abstract Absorption cross-sections of nine halomethanes (CCl4, CHCl3, CH2Cl2, CH3Cl, CFCl3, CF2Cl2, CF3Cl, CHFCl2, and CHF2Cl), measured between 174 and 250 nm for temperatures ranging from 225 to 295 K, are presented with uncertainties ranging from 2 to 4% and compared with previous determinations made for comparable temperature ranges. The largest temperature effect which takes place near the absorption threshold, decreases the absorption cross-section up to 50% for highly chlorinated methanes, but is negligible for molecules highly stabilized by hydrogen and/or fluorine. Extrapolated values for temperatures of aeronomical interest are presented, as well as parametrical formulas which give absorption cross-section values for given wavelength and temperature ranges.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00048042
Permalink