Direct evidence for the β-hydride elimination mechanism in the decomposition of triethylgallium on GaAs(100)

Autor:	John G. Ekerdt, Robert D. Culp, M. T. McEllistrem, Alan H. Cowley, K. C. Wong, Brian G. McBurnett
Rok vydání:	1998
Předmět:	Hydride Thermal desorption spectroscopy Surfaces and Interfaces Condensed Matter Physics Surfaces Coatings and Films chemistry.chemical_compound Elimination reaction chemistry Desorption Kinetic isotope effect Materials Chemistry Physical chemistry Ethyl group Triethylgallium Chemical decomposition
Zdroj:	Surface Science. 396:260-265
ISSN:	0039-6028
DOI:	10.1016/s0039-6028(97)00674-2
Popis:	Decomposition of the surface ethyl group formed by dissociative adsorption of triethylgallium (TEGa) on GaAs(100) is investigated using temperature programmed desorption. Deuterium labeling indicates that decomposition of the surface ethyl group proceeds exclusively through a β-hydride elimination reaction mechanism without any scrambling between α- and β-hydrogens. For undeuterated TEGa (TEGa-d0), the surface ethyl group decomposes and desorbs simultaneously as C2H4 and H2 at 600 K. For perdeuterated TEGa (TEGa-d15), the desorption of C2D4 and D2 occurs at a slightly higher temperature (630 K). Partially deuterated TEGa (TEGa-d6), with deuterium on the α-carbons, results in H2 and C2H2D2 as desorption products at 600 K. A kinetic isotope effect of 8 ± 5 kJ mol−1 for hydride versus deuteride transfer is determined, which is consistent with cleavage of the CβH bond in the transition state, and with tunneling.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::d197a7b799e7cf776db5ace741c22ace https://doi.org/10.1016/s0039-6028(97)00674-2 Zobrazit plný text záznamu Full Text from ScienceDirect