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Why does DoD fund Basic Research? -Generates discoveries, new knowledge, and improved understanding; -Achieves technological superiority; -Prevent technological surprise; -Educates scientists and engineers in physical science disciplines; -Ensures that scientific expertise and engineering rigor supports DoD technical decisions; -Sustains the human talent and research infrastructure., Presented at the GOMAC Tech-08 (Government Microcircuit Applications & Critical Technology) Technology Conference: Microsensor Technologies Enabling Information on Demand. Held in Las Vegas, NV on 17-20 March 2008. The original document contains color images.

The reaction of (CH3)2Si(NMe2)2 with BlOH14 Yields a polymer, BlOH12. Me2NSi(CH3)2NMe2n, whose pyrolysis in a stream of ammonia gives hexagonal boron nitride containing 'a' little silicon nitride. In contrast, CH3(H)Si(NMe2)2 reacts with BlOH14 to give 1,2-dimethyl-1,2-disila-closo-dodecaborane(12) (DMSB) , an air-sensitive solid, the structure of whose 1:1 benzene solvate was determined by X-ray diffraction. This compound crystallizes in the space group P ccn ( 56) with a 10.081(1) b = 10 . 666(8) A, c = 16.130(5) A, V = 1734(2)A3 and Z = 4. Final R = 0.044 and RW = 0.058. The 1H, 13C, 29Si and 11B NMR spectra and mass spectrum of DMSB are reported. Its vibrational spectrum (Raman, 5-3600 cm-1 ; IR, 200-3600 cm-1) has been measured and compared with that of ortho- carborane. A study of its He(I) photoelectron spectrum led to the conclusion that DMSB is the most electro rich cluster of type XYB1OH1O with two adjacent main group element centers known.

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.

The icosahedral carboranes, especially those in which the two cluster carbon atoms are vicinal (o-carboranes), have received much attention since the first reports of their existence in 1963. Notably absent in the many publications on this class of boron cluster compounds over the intervening 25 odd years have been examples of icosahedral clusters in which the two monosubstituted carbon atoms of an o-carborane have been replaced by two monosubstituted silicon, germanium, tin or lead atoms. We report here the synthesis and structural characterization of 1, the first such Group IVA analog of an o-carborane: 1,2-dimethyl-1,2-disila-closo-dodecaborane(12) (or 1,2- dimethyl-o-silaborane). This compound is notable also in that it is the first example of a formal derivative of a disilyne, CH3Si triple bonds SiCH3 in the present case, a class of unsaturated organosilicon compounds of which there are to date no known examples. Keywords: Carboranes, Silaboranes, Organosilicon compounds, Organic chemistry, Silicon, Boron.

Ceramic materials whose properties are attractive for high technology applications often fail to realize their full potential of usefulness due to an inability to be fabricated into complex, durable shapes. One such class of materials is that of the boron-containing ceramics, e.g., boron carbide, boron nitride, boron phosphides, aluminum boride, and boron silicides. We now report the results of an effort to extend the use of preceramic polymers to boron- containing materials. The motivation for this work was to utilize processable materials which give, in general, boron carbide as the major ceramic phase upon pyrolysis. A route to soluble boron-containing polymers has been developed. The synthesis and characterization of phosphorus-containing monomeric and polymeric derivatives of decaborane (B10H14) are given. Preparation and characterization of boron-containing ceramic materials from these molecular and macromolecular species are discussed. Success has been achieved in the areas of ceramic fiber and monolith production and in the area of binder applications for composites of advanced ceramic materials.

The pyrolytic conversion of bis-Lewis base adducts of decaborane(14), L.B sub 10 H sub 12.L (L= neutral monophosphine) and phosphonium salts of the (B sub 10 H sug 10)2- anion (e.g., (Ph sub 4 P sub (+)2, etc.), to ceramic materials has been studied. All species examined served as binders for a variety of non-oxide refractory ceramic powders (e.g., B sub 4 C, BN, BP, B sub 13 P sub 2, SiC, Si sub 3 N sub 4, B, C, A1N). Keywords: Boron carbide, Organophosphorous compounds.