A spectroscopic study of Cl2O3

Abstract

The UV absorption spectrum of dichlorine trioxide, Cl₂O₃ has been recorded in the wavelength range 220–340 nm and at 223 K using a recently developed flash photolysis–kinetic UV absorption spectroscopy apparatus. Cl₂O₃ was generated in the reaction between ClO and OClO following the partial photolysis of OClO. The spectrum obtained is smooth, and shows a peak at 267 nm, where σ= 1.76 × 10^–17 cm² molecule^–1(base e). Results are broadly consistent with previous determinations of the spectrum, although we report higher cross-sections in the long-wavelength tail of the absorption. The discrepancies between these and previous measurements are discussed, together with the atmospheric implications of this work.