Ab initio direct dynamics studies on the reaction Br + SiH4

The dynamical properties of the reaction Br + SiH4 → products have been investigated theoretically. The optimized geometries, frequencies and energies of reactants, transition states and products are calculated at the MP2/6-311G(d,p) and MP2/6-311G(2d,p) levels. The energy profiles are refined by performing a series of single-point energy calculations at the MP4(SDQ)/6-311+G(2df,2p)//MP2/6-311G(d,p) level. The rate constants are calculated by using canonical variational transition state theory (CVT) incorporating with the small-curvature tunneling (SCT) correction in the temperature range 200-3000 K, and the results are in excellent agreement with the available experimental values. H-abstraction reaction channel is the major channel for the title reaction.