Gallium high-purity

High-purity gallium is attacked only slowly by mineral acids. 

A mixture of (C H ) , TiCl, and AlCl is useful for polymerizing C —olefins (85). The dimerization of propylene is accompHshed by using catalysts such as Ni(PR2)4 (86). Alkylphosphines such as / fZ-butylphosphine [2501-94-2] have been proposed as a substitute for high purity phosphine in the production of the semiconductor gallium phosphide (87). 

Eig. 3. Electron (—) and hole (-) velocities versus electric field for high purity siUcon, Si germanium, Ge and gallium arsenide, GaAs, at 300 K (26). 

For relatively simple matrices, such as pure metallic CRMs synthetic reference materials for direct calibration were prepared and used, for example Bi, Cd, Hg, Pb and T1 in high purity gallium (HUtenkamp and Jackwerth 1988), Ag in copper (Pau-wels et al. 1990) and Au and Pd in silver (Hinds 1993). Direct calibration by solid biological materials with added analyte belongs also to these quite successfully applied techniques (Hofmarm et al. 1992). 

Antimony alloys have many commercial applications. The metal makes its alloys hard and stiff and imparts resistance to corrosion. Such alloys are used in battery grids and parts, tank linings, pipes and pumps. The lead plates in the lead storage batteries constitute 94% lead and 6% antimony. Babbit metal, an alloy of antimony, tin, and copper is used to make antifriction machine bearings. Alloys made from very high purity grade antimony with indium, gallium and bismuth are used as infrared detectors, diodes, hall effect devices and thermoelectric coolers. 

Gallium arsenide is produced in polycrystaUine form as high purity, single crystals for electronic applications. It is produced as ingots or alloys, combined with indium arsenide or gallium phosphide, for semiconductor apphcations. 

The compound is prepared by vapor phase reaction of gallium suboxide, Ga20 and phosphorus. It is produced in polycrystaUine form or as single crystals or whiskers in high purity grade for use in semiconducting devices. 

J. W. Gramlich and L. A. Mach Ian, Isotopic Variations in Commercial High-Purity Gallium, Anal. Chem. 1985,57, 1788. 

The conventional method for quantitative analysis of gallium in aqueous media is atomic absorption spectroscopy (qv). High purity metallic gallium is characterized by trace impurity analysis using spark source (15) or glow discharge mass spectrometry (qv) (16). 

The following preparation of gallium trichloride is applicable to both large- and small-scale reactions.4 Gallium trichloride is produced quantitatively and in high purity. Directions for the manipulation of this air-sensitive compound on the bench top or in a dry box are included. 

---