Formation of CH₃ radicals in the decomposition of trimethyl aluminum on hot solid surfaces

The thermal decomposition of trimethyl aluminum on different hot substrates has been studied under low-pressure conditions. The products of the decomposition reaction were analyzed mass-spectrometrically using electron-impact and resonance-enhanced multiphoton ionization. The results of this study reveal that only CH₃ appears as a gas-phase product and stable compounds such as CH₄ and C₂H₆ are not observed under the conditions employed. The apparent activation energy for the production of the CH₃ radical from the Al-coated hot substrates is measured to be 11 ± 2 kcal/mole.