The UV absorption spectrum of the simplest Criegee intermediate CH2OO

Abstract

SO₂ scavenging and self-reaction of CH₂OO were utilized for the decay of CH₂OO to extract the absorption spectrum of CH₂OO under bulk conditions. Absolute absorption cross sections of CH₂OO at 308.4 and 351.8 nm were obtained from laser-depletion measurements in a jet-cooled molecular beam. The peak cross section is (1.23 ± 0.18) × 10⁻¹⁷ cm² at 340 nm.