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Ethyl iodide and ethyl chloride have been used as reactants to produce ethyl fragments on the stoichiometric α-Cr₂O₃ (1012) surface by means of thermal dissociation. Ethyl iodide is dissociated giving iodine adatoms and ethyl fragments bound to surface Cr cation sites, while ethyl chloride is dissociated giving chlorine adatoms and ethyl fragments. No oxygenated products are observed in thermal desorption, suggesting the 3-coordinate lattice oxygen on the stoichiometric α-Cr₂O₃ (1012) surface is very stable, and no nucleophilic attack occurs at the carbon atoms on surface ethyl fragments. For both reactants, the only reaction products observed are ethylene gas (CH₂=CH₂), ethane gas (CH₃-CH₃), hydrogen gas (H₂) and halogen adatoms (Clads or Iads). In thermal desorption experiments, all the gas phase products from ethyl chloride are produced in a reaction-limited, high temperature desorption feature attributed to a rate limiting β-hydride elimination from surface ethyl fragments. Similar product desorption features are observed for the reaction of ethyl iodide. However, the reaction of ethyl iodide also produces ethylene and ethane via a low temperature, desorption-limited reaction channel. It is postulated that I adatoms produced in the reaction of ethyl iodide thermal desorption might somehow promote a low temperature route to products that Cl adatoms do not.

A study of the interaction of cobalt-60 radiation with frozen ethyl iodide in both the glass and polycrystalline states. The final reaction products of the radiolysis were measured and compared with the intermediate reaction species that were observed with an electron spin resonance spectrometer. (Author)

A single-pulse shock tube has been designed, constructed and used to study the kinetics of methyl iodide and ethyl iodide pyrolysis in the range 2700-2900 K. For methyl iodide the chief products are methane, ethylene, acetylene and iodine and for ethyl iodide they are the same plus ethane. The experimental data seem to support a mechanism in methyl iodide pyrolysis that is free-radical in nature and involves one activation step. In the ethyl iodide case there appear to be two separate free-radical activations, one involving cleavage of the carbon-carbon bond and the other that of the carbon-iodine bond. (Author)