Kinetics and Mechanism of Transformations of Aliphatic Alcohol Molecules Under Multiphoton IR Excitation

Abstract

The main channels for transformations of C₂H₅OH, iso-CH₃H₇OH and n-C₃H₇OH molecules under IR multiphoton excitation are the monomolecular reactions of dehydration (1), and Cα−Cβ bond breaks (2). The ratio of the yields of reactions (1) and (2), γ, is determined by the molecules' structure, radiation energy density, the pressure of alcohol vapors and inert gas. The direction of the alcohol molecules' transformations under IR MPE, under thermal equilibrium conditions, differs from pyrolysis, when the chain processes of C₂H₅OH and C₃H₇OH molecules dehydrogenation, and CH₄ splitting-out from n-C₃H₇OH molecules are developing. Reactions of H and CH₃ radicals with alcohol molecules under laser initiation do not lead to the development of chains due to the high rate of H atoms diffusion from reaction zone and effective recombination of CH₃ radicals.