Encounter complexes methyl chloride reactions

Most of these theoretical investigations have been carried out using methyl compounds as the substrate. For example, the Sn2 reaction between OFT and methyl chloride has been investigated for non-linear and linear collisions using ab initio molecular dynamics calculations.105 The potential energy surface was calculated at the MP2/6-311-I— -G(2df,2pd) level of theory and the collision energy was set at 25 kcal mor1. The results for 495 trajectories indicated that the reactants pass from the initial encounter complex to the transition state in 0.02 ps and to the product encounter... 

B3LYP/6-311+- -G -level calculations have been used to predict the structure of the encounter complex (68) for the. S n2 reaction between F and methyl chloride in the presence of one molecule of water.106 Structure (68) was chosen as the encounter complex even though it does not have the lowest energy, but because it has the greatest negative charge on fluorine. Structure (69) is the encounter complex for the reverse reaction. 

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