Arrhenius Parameters for the System (CH3)3Si + D2 ⇄ (CH3)3SiD + D. The (CH3)3Si — D Bond Dissociation Energy

The Arrhenius parameters of the reaction (3) equation image have been determined relative to the recombination of the trimethylsilyl radicals equation image yielding EA (3) — 1/2EA(6) = 67 ± 6 kJ mol−1 and A(3)/A (6)1/2 = 10−7±0.5 cm3/2 s−1/2. The rate constant for the back reaction (‐3) equation image has been determined to be equation image . Assuming a negligible activation energy for the recombination reaction (6) gives HD0((CH3)3Si — D) = 388 ± 7 kJ mol−1 in accordance with the accepted literature value. In the experimental part a pulsed Hg sensitized photolysis‐resonance absorption technique is described to obtain rate constants for hydrogen atom‐molecule reactions. For testing the apparatus the rate constants equation image at room temperature have been determined.