Ab initio Study of the Potential Energy Surface and Product Branching Ratios for Reaction of O(1D) with C2H5Cl

The potential energy surface of O(1D)+C2H5Cl reaction was studied using QCISD(T)/6-311++G(d,p)//MP2/6-31G(d,p) method. The calculations reveal an insertion-elimination mechanism. The insertion reaction of O(1D) and C2H5Cl produces two energy-rich intermediates, IM1 and IM2, which subsequently decompose into various products. The calculations of the branching ratios of various products formed through the two intermediates were carried out using RRKM (Rice-Ramsperger-Kassel-Marcus) theory at the collision energies of 0, 20.9, 41.8, 62.7, 83.6, 104.5, and 125.4 kJ/mol. HCl is the main decomposition product for IM1; CH2OH is the main decomposition product for IM2. Since IM1 is more stable than IM2, HCl is probably the main product of the O(1D)+C2H5Cl reaction.