RADICAL AND MOLECULAR PROCESSES IN THE THERMAL-DECOMPOSITION OF TRIMETHYL AND TRIETHYL STIBINES

The gas phase pyrolysis of trimethylstibine and triethylstibine has be en studied by infrared laser powered homogeneous pyrolysis. The role o f free radicals in both homogeneous and surface decomposition was inve stigated by matrix isolation electron spin resonance (ESR) spectroscop y. For trimethylstibine, the major process at low pressures is methyl radical loss and subsequent abstraction of hydrogen from the starting material. For triethylstibine, the major process in decomposition on h eated quartz surfaces is ethyl radical loss, whereas the gas phase stu dies suggest a significant molecular elimination route. For both compo unds, material deposited from the gas phase is essentially pure antimo ny, indicating that homogeneous reactions play little part in carbon i ncorporation.