The dynamics of O(3P) + deuterated hydrocarbons: influences on product rotation and fine-structure state partitioning
Abstract
The dynamics of the reactions O(3P) + CH4/CD4 and O(3P) + cyclo-C6H12/C6D12 have been investigated experimentally. Translationally hot O(3P) atoms were generated by laser photolysis of NO2 at 266 nm. The rotational and fine-structure state distributions in the nascent product OH or OD radicals were determined by laser-induced fluorescence. The deuterium-labelled reactants have provided confirmation of the main features of the product-state partitioning observed previously for normal-hydrogen compounds. Only OH ν′ = 0 is detectable from CH4. CD4 also produces predominantly OD ν′ = 0, with ν′ = 1 being just detectable with an estimated branching ratio of ∼ 0.06.
Both cyclo-C6H12 and C6D12 produce significant yields of ν′ = 0 and 1 products. Despite the opposite trend in exothermicities, the ν′ = 0 products are rotationally hotter from methane than from