Mechanistic studies and rate coefficients calculations of hydrogen abstraction from ethanol by methyl peroxy radical and hydroperoxyl radical

The reactions of XO2∙ (X = CH3, H) with C2H5OH were investigated over the temperature range of 300–1500 K. The geometries of the stationary points were optimised at the MP2/aug-cc-pVTZ level and the energetics were refined at the CCSD(T)/aug-cc-pVTZ and the QCISD(T)/cc-pVTZ levels of theory. Six possible hydrogen abstraction channels were explored and it showed that the channels producing XO2H and CH3CHOH were favourable. The stable prereactive complexes were identified and their role was considered in the rate coefficient calculations. The rate coefficients have positive temperature dependence and the tunneling effect is more important at low temperature than at high temperature.