High-Level Theoretical Studies on the Gas-phase Identity Methyl Transfer Reactions

초록

The gas-phase identity methyl transfer reactions, X + CH3X, have been investigated with X=H,F,Cland Br at the MP2, B3LYP , QCISD and QCISD(T) levels using 6-311++G(3df,2p) basic sets. The DFT overestimates while the MP2 and QCISD methods underestimate the electron correlation effects relative to the highest level QCISD(T) results, which are in general in good agreement with the available experimental values.