Accession Number : ADA259543


Title :   Aspects of the Chemistry of Vinylarsenic Compounds. The Preparations of Divinylarsinic Acid, Tetravinyldiarsine Oxide, and Tetravinyldiarsine, and the X-Ray Crystal Structure of the Helical Divinylarsinic Acid


Descriptive Note : Interim rept. 1 Jul-1 Dec 1992


Corporate Author : FLORIDA STATE UNIV TALLAHASSEE


Personal Author(s) : Goedken, Virgil L ; Brough, Lawrence F ; Rees, Jr, William S


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a259543.pdf


Report Date : 17 Dec 1992


Pagination or Media Count : 30


Abstract : Among the compound semiconductors, Gallium Arsenide is perhaps one of the most widely studied. Its direct bandgap makes it a good candidate for laser applications, while a range of (AL,Ga)As compositions find use in an array of high-speed electronic devices. One popular method for the production of epitaxial thin films of GaAs is organometallic vapor phase epitaxy(OMVPE). In the common manifestation of the OMVPE synthesis, Arsine is the primary source of the group 15 element for the final material. The combination of the high vapor pressure and high toxicity of this congener of ammonia has led researchers to explore a variety of alternate routes to produce high quality GaAs. Another potential source of elemental arsenic, the tetraalkyldiarsines, is indicated. Accordingly, we recently initiated an investigation into the feasibility of utilizing this class of compounds as relatively less toxic precursors to the arsenic necessary for GaAs growth. Tetravinyldiarsine (1) was prepared by coupling divinylarsenic(III) bromide (3) with lithium dispersion in diethyl ether. Tetravinyldiarsine oxide (2) and divinylarsinic acid (3) were obtained as primary and secondary by-products, respectively. The molecules are linked by hydrogen bonds to form an extended, linear, helical chain along the twofold screw axis. Dihedral angles between planes containing the vinyl carbons and the AS=O bond are -5.2 degrees and 12.2 degrees, which strongly suggests the presence of conjugative interaction. Spectroscopic data are reported for compounds 1, 2, and 3.


Descriptors :   *CHEMISTRY , *VINYL RADICALS , *ARSENIC COMPOUNDS , CRYSTAL STRUCTURE , NUCLEAR MAGNETIC RESONANCE , INFRARED SPECTROSCOPY , SPECTROSCOPY , ORGANOMETALLIC COMPOUNDS , ULTRAVIOLET SPECTROSCOPY , ACIDS , OXIDES , CARBON , X RAYS , HYDROGEN , CHEMICAL BONDS


Subject Categories : Organic Chemistry
      Physical Chemistry
      Crystallography
      Atomic and Molecular Physics and Spectroscopy


Distribution Statement : APPROVED FOR PUBLIC RELEASE