Premium
Pressure and temperature‐dependent quantum yields for the photodissociation of acetone between 279 and 327.5 nm
Author(s) -
Blitz M. A.,
Heard D. E.,
Pilling M. J.,
Arnold S. R.,
Chipperfield M. P.
Publication year - 2004
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2003gl018793
Subject(s) - photodissociation , acetone , quantum yield , troposphere , analytical chemistry (journal) , wavelength , chemistry , photochemistry , materials science , atmospheric sciences , physics , optics , environmental chemistry , organic chemistry , fluorescence
The photodissociation of acetone has been studied over the wavelength (λ) range 279–327.5 nm as a function of temperature ( T ) and pressure ( p ) using a spectroscopic method to monitor the acetyl (CH 3 CO) radical fragment. Above 310 nm the quantum yield (QY) is substantially smaller than previous measurements, and decreases with T . The QYs for production of CH 3 CO + CH 3 and CH 3 + CH 3 + CO have been parameterised as a function of λ, p and T and used to calculate the altitude dependence of the photolysis frequency. In the upper troposphere (UT) the acetone photolysis lifetime is a factor of 2.5–10 longer, dependent upon latitude and season, than if the previously recommended QYs are used.