Gallium crystallinity

Wallace C H, Rao L, Kim S-H, Heath J R, Nicol M and Kaner R B 1998 Solid-state metathesis reactions under pressure a rapid route to crystalline gallium nitride Appl. Phys. Lett. 72 596... 

Gainum (HI) Ga203 is the single gallium oxide that is stable under normal conditions. Like alumina, it exists iu several crystalline forms. The... 

Complex Formation. B-Ttichlorobora2iQe was reported to readily form crystalline adducts of uncertain stmcture with pyridine (131). The Lewis acids aluminum tribromide or gallium trichloride form 1 1 adducts with hexamethylbota2iQe (eq. 36) ia which the metal atom coordinates with a nitrogen with loss of planarity of the ring (132,133). 

The covalent nature of III-V materials causes problems for preparation of highly crystalline nanoparticles and thin films. A single-molecular precursor approach was employed to produce III-V nanoparticles of InP and GaP using the indium/gallium diorganophosphide compounds... 

Various inorganic semiconductors (p-type and/or n-type nonoxide semiconducting materials) sucb as amorphous or crystalline silicon (a-Si or c-Si), gallium arsenide (GaAs), cadmium telluride (CdTe), gallium phosphide (GaP), indium phosphide (InP), copper... 

There are three main thin-film PV cells under development at present amorphous Si, CdTe/CdS, and Cl(G)S/CdS [C1(G)S refers to copper indium (gallium) selenide]. Of these, the last two are polycrystalline (as opposed to amorphous), and both normally employ CD CdS. Crystalline Si cells are not thin films, being at least tens and usually hundreds of microns in thickness, compared to the few microns of active thickness of the thin-fihn cells. 

Metallic liquids can also experience fractional crystallization. The abundances of trace elements such as gold, gallium, germanium, and iridium and the major element nickel in various classes of iron meteorites vary because of the separation of crystalline metal phases (kamacite or taenite). 

No structure of a stable monomeric iminoalane is currently available. However, the p-diketiminate stabilized monomeric [(L)]AINC6H3(C6H2Pr 3-2,4,6)2-2,6] (L = HC C-(Me)N(Dipp) 2) is believed to have a very similar structure to its gallium analogue (cf. Section 8.3.5) which has a very short Ga—N distance of 1.701 A consistent with Ga—N multiple bonding. It readily underwent intramolecular additions to the Al—N bond to give crystalline products. For an account of the chemistry of A1(L), see Ref. 184. 

The benzobisazole family of rigid-rod polymers is soluble in acidic solvents such as PPA, methanesulfonic acid, chlorosulfonic acid, 100% sulfuric acid and Lewis acid salts such as antimony trichloride and bismuth trichloride. More recently, PBZT has been reported [22] to form liquid crystalline solutions in nitromethane containing aluminum trichloride or gallium trichloride. Since the glass transition temperature of these materials is above their decomposition temperature, they must be processed from solution. 

Crystalline salts containing tetra-, penta- and hexa-isothiocyanate complex anions can be isolated from aqueous or methanolic solutions.507 Frequencies v(Ga—NCS) occur in IR spectra at 350 cm-1 in four-coordinate or 250 cm-1 in six-coordinate species. Although powder patterns have been reported, single-crystal X-ray data are lacking for gallium thiocyanates. Some gallium selenocyanide complexes Ga(NCSe)3Ls and Ga(NCSe)4 have been prepared.508 Attempts to obtain Ga(NCS)3 or Ga(NCSe)3 appear to have failed. 

Galliuni (III). Ga C is the single gallium oxide that is stable under normal conditions. Like alumina, it exists in several crystalline forms. The most stable form is the beta oxide, mp ca 1725°C, density 5.88 g/cm3. The density of (X-Ga C is 5.18 g/cm3. 

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