Kinetic studies of the reactions of hydroxyl radicals with the methyl-substituted silanes SiHn(CH3)4 − n (n=0 to 4) at room temperature

Abstract The flash-photolysis resonance-fluorescence method has been employed at 293–297 K to measure rate constants for the reactions of OH with SiH 4 , Si(CH 3 )H 3 , Si(CH 3 ) 2 H 2 , Si(CH 3 ) 3 H, and Si(CH 3 ) 4 of (1.2 ± 0.2) × 10 −11 , (3.3 ± 0.4) × 10 −11 , (4.4 ± 0.5) × 10 −11 , (3.1 ± 0.4) × 10 −11 , and (1.2 ± 0.2) × 10 −12  molecule −1  cm 3  s −1 , respectively. The uncertainties are 95% confidence intervals (see text). The results reveal that the per Si–H bond reactivity towards OH increases with the degree of methylation, and that Si(CH 3 ) 2 H 2 is the most reactive member of the series.