Kinetics of hydrogen abstraction from chloromethanes by the hydroxyl radical: A computational study

Hydrogen abstraction reactions between chloromethanes and the hydroxyl radi cal have been investigated by using ab initio molecular orbital theory. Geo metry optimizations and vibrational frequency calculations have been perfor med for all the reactants, products, and transition states at the MP2=full/ 6-311G(d,p) level. Subsequently, single point energy calculations have been carried out at the MP2=full/6-311G(2df,2p) and QCISD(T)/6-311G(2df,2p) lev els for all the species. The transition state theory including the tunnelin g contributions has been used for estimating the rate constants for the hyd rogen abstraction. The results obtained from our PMP2 and QCISD(T) calculat ions with the larger 6-311G(2df,2p) basis set have been found to be in good agreement with the available experimental values.