KINETIC INVESTIGATIONS OF THE REACTIONS OF TETRAMETHYLGERMANE, TETRAETHYLGERMANE, TETRAMETHOXYGERMANE AND 3,3-DIETHYLPENTANE WITH O(P-3) ATOMS

The rates of the reactions of the alkylgermanes and 3,3-diethylpentane with atomic oxygen in the ground state [O(P-3)] have been measured in a continuous flow reactor with molecular beam sampling and mass spect rometric detection. The oxygen atoms were produced by chopped microwav e discharges in a mixture of oxygen with helium as carrier gas; in all cases the reactions have been examined in an excess of oxygen atoms i n the temperature range between 298 and 773 K. The following Arrhenius expressions for the bimolecular rate constants were obtained: k(T)(te tramethylgermane) = (1.1 +/- 0.2) X 10(13) X exp (-(2680 +/- 270) K/T) cm(3)/(mol X s) k(T)(tetraethylgermane) = (1.8 +/- 0.2) X 10(13) X ex p (-(1620 +/- 160) K/T) cm(3)/(mol X s) k(T)(tetramethoxygermane) = (1 .4 +/- 0.3) X 10(13) X exp (-(1990 +/- 200) K/T) cm(3)/(mol X s) k(T)( 3,3-diethylpentane) = (1.2 +/- 0.2) X 10(13) X exp ((-(2100 +/- 210) K /T) cm(3)/(mol X s). The activation energies of these reactions are E- A(Ge(CH3)(4)) = 22.3 kJ/mol, E-A(Ge(C2H5)(4)) = 13.5 kJ/mol, E-A(Ge(OC H3)(4)) = 16.6 kJ/mol and E-A(C(C2H5)) = 17.5 kJ/mol.