Hot-atom—laser-induced-fluorescence experiments on the reaction of H(2S) with CO2

Abstract

The nascent rotational and fine-structure state distributions in OH(υ = 0) produced in the endothermic reaction H + CO2 → OH + CO have been measured with hot hydrogen atoms from the photodissociation of HBr at 193 nm. Considerable OH rotational excitation broadly peaked at aroundK = 11 is observed. The OH spin doublets are produced statistically (±10%). The partitioning between the λ doublets is non-statistical with a strong preference for the π+ component (σ(π+)/σ(π−) = 3.0 ± 1.0), consistent with a planar HOCO intermediate whose OCOH bond breaks in that plane.