KINETIC INVESTIGATIONS OF THE REACTIONS OF MONOSILANE, MONOCHLOROSILANE, DICHLOROSILANE, TRICHLOROSILANE AND TETRACHLOROSILANE WITH ATOMIC OXYGEN IN THE ELECTRONIC GROUND-STATE (O(P-3))

The rates of the reactions of monosilane, monochlorosilane, dichlorosi lane, trichlorosilane and tetrachlorosilane with atomic oxygen in the ground state (O(3P)) were measured in a discharge flow system with mas s spectrometric detection. The measurement of the reaction of monosila ne with atomic oxygen is compared with measurements of other groups [1 - 5]. For the other compounds no measured data for the reaction with 0-atoms were found in the literature. All measurements were performed in an excess of 0-atoms in the temperature range 293 K < T < 773 K. Th e obtained second order rate constants can be represented by straight lines in an Arrhenius plot. They can be approximated by the following expressions: Monosilane: k(T) = (20 +/- 4)10(12)* exp(-1390 +/- 140 K /T)cm3 mol-1 s-1. Monochlorosilane: k(T) = (11 +/- 2)10(12)* exp(-132 0 +/- 130 K/T)cm3 mol-1 s-1. Dichlorosilane: k(T) = (10 +/- 2)10(12)* exp(-1480 +/- 150 K/T)cm3 mol-1 s-1. Trichlorosilane: k(T) = (8.5 +/- 1.7)10(12)* exp(-1630 +/- 320 K/T)cm3 mol-1 s-1. Tetrachlorosilane: k(T) < 10(8) cm3 mol-1 S-1 in the applied temperature range.