Accession Number : ADA331934

Title :   New Pnictinogallanes H2GaE(SiMe3)23 (E = P, As) - Formation, Structural Characterization, and Thermal Decomposition to Afford Nanocrystalline GaP and GaAs

Descriptive Note : Technical rept.

Corporate Author : DUKE UNIV DURHAM NC DEPT OF CHEMISTRY

Personal Author(s) : Janik, J. F. ; Wells, R. L. ; Young, V. G. ; Rheingold, A. L. ; Guzei, I. A.

PDF Url : ADA331934

Report Date : 24 NOV 1997

Pagination or Media Count : 30

Abstract : The new compounds, H2GaE(SiMe3)23, E = P (1), As (2), the first authenticated examples of a phosphinogallane and an arsinogallane, containing the GaH2 moiety, are prepared via efficient dehydrosilylation from the respective combinations of H3Ga.NMe3 and E(SiMe3)3 in diethyl ether or toluene. Compounds 1 and 2 are characterized by elemental analysis, NMR, IR, and mass spectrometry. Single-crystal X-ray structural studies show that the molecular structures of 1 and 2 feature a flattened six-member ring of alternating Ga and E centers. Both compounds are reasonably stable at -30 deg C but spontaneously decompose at ambient temperatures, 2 noticeably faster than 1, with the evolution of HSiMe3, H2, and E(SiMe3)3. The pyrolysis of 1 yields nanocrystalline GaP while the pyrolysis of solids from decayed 2 results in nanocrystalline GaAs as determined from XRD studies. Under applied pyrolysis conditions, the thermally accelerated dehydrosilylation of the precursors is accompanied by a side-evolution of CH4 and retention of small quantities of amorphous Si/C phases.

Descriptors :   *THERMAL PROPERTIES, *GALLIUM ARSENIDES, *ORGANOMETALLIC COMPOUNDS, *DECOMPOSITION, *GALLIUM PHOSPHIDES, TEMPERATURE, CRYSTAL STRUCTURE, METHYL RADICALS, STRUCTURAL PROPERTIES, SINGLE CRYSTALS, SOLIDS, X RAYS, SILICON, CHEMICAL REACTIONS, RETENTION(GENERAL), ORGANIC COMPOUNDS, ETHERS, GALLIUM, MOLECULAR STRUCTURE, ARSINES, PHOSPHINE, PYROLYSIS, ETHYL RADICALS, MASS SPECTROMETRY, TOLUENES.

Subject Categories : Inorganic Chemistry
      Organic Chemistry
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE