EXPERIMENTAL AND THEORETICAL-STUDIES OF THE REACTION OF ATOMIC-HYDROGEN WITH SILANE

The kinetics of the reaction H (1(2)S) + SiH4 have been measured from 290 to 660 K by the flash photolysis-resonance fluorescence technique. The results are summarized by k = (1.78 +/- 0.11) X 10(-10) exp[ - (16.0 +/- 0.2) kJ mol-1/RT] cm3 s-1 with a confidence interval of about +/- 10%. The transition state for direct H-atom abstraction was investigated theoretically, at up to the GAUSSIAN 2 ab initio level. A transition state theory analysis of the abstraction channel gives excellent accord with the measurements, which suggests that H-2 + SiH3 are the dominant products. An expression for the reverse reaction is given. An extrapolated k from 290 up to 2000 K, which includes a Wigner tunneling correction, is k = 2.44 X 10(16) (T/K)1.903 exp(- 1102 K/T) cm3 s-1.