CF 3C(O)C1: Temperature-dependent (223–298 K) absorption cross-sections and quantum yields at 254 nm

Abstract

UV absorption cross-sections of trichloroacetyl chloride (CF 3C(O)Cl) have been measured using two different apparatuses with spectral resolutions of 0.05 and 0.2 nm in the wavelength range 200–330 nm at temperatures ranging from 223 to 298 K. Photolysis studies of CF 3C (O) C1 in N 2, air/C 2H 6 mixtures and air have been performed at 254 nm. Quantum yields for the dissociation of CF 3C (O) C1 as a function of pressure and product quantum yields for C1 2 and CO at 296 K have been determined. The temperature-dependent absorption cross-sections and new quantum yields were used to calculate photodissociation rate-constants for CF 3C(O)C1 at different solar zenith angles as a function of altitude. Temperature effects of the photodissociation rate constants are discussed.