56668-59-8

Upstream product

• 7440-55-3 gallium 
• 7440-02-0 nickel 

Relevant academic research and scientific papers

Surface plasmons in NiGa and CoGa alloys

Electron energy losses at the surface of Ga, NiGa and CoGa have been studied by X-ray photoemission spectroscopy (XPS). These features are interpreted as being due to surface plasmons. For Ga metal the experimental result is in good agreement with the surface plasmon energy obtained by a free-electron model. At the surface of CoGa and NiGa alloys, the corresponding energy is about 1 eV higher than that of pure Ga metal. This result is discussed in the framework of a free-electron model as well.

Single crystal studies on boron-rich τ-borides Ni23-xM xB6 (M=Zn, Ga, In, Sn, Ir)The surprising occurrence of B4-tetraheda as a normal case?

Single crystals of the cubic τ-borides Ni23-xM xB6 (M=Zn, Ga, In, Sn, Ir) were synthesised from the elements at temperatures between 1200 and 1500 °C. The structure refinements show that the existence of boron-rich phases is quite common. Starting from the idealised composition Ni20M′3B6 a part of the metal atoms on site 8c is substituted by B4 tetrahedra. For M′=Ga a complete exchange seems to be possible leading to the composition Ni20GaB14. For M′=Zn and Sn the formation of solid solutions is less extended. For M′=In no exchange is observed but an unusual pattern of Ni/In distribution is observed. With M=Ir mixed occupations occur for all sites and the boron content varies, too. All compositions were confirmed by EDX measurements.

Synthesis and crystal structures of the new metal-rich ternary borides Ni12AlB8, Ni12GaB8 and Ni 10.6Ga0.4B6-examples for the first B 5 zig-zag chain fragment

Single crystals of the new borides Ni12AlB8, and Ni10.6Ga0.4B6 were synthesized from the elements and characterized by XRD and EDXS measurements. The crystal structures were refined on the basis of single crystal data. Ni12AlB8 (oC252, Cmce, a=10.527(2), b=14.527(2), c=14.554(2) , Z=12, 1350 reflections, 127 parameters, R1(F)=0.0284, wR2(F2)=0.0590) represents a new structure type with isolated B atoms and B5 fragments of a BB zig-zag chain. Because the pseudotetragonal metric crystals are usually twinned. Ni10.6Ga0.4B6 (oP68, Pnma, a=12.305(2), b=2.9488(6), c=16.914(3) , Z=4, 1386 reflections, 86 parameters, R1(F)=0.0394, wR2(F2)=0.104) is closely related to binary Ni borides. The structure contains BB zig-zag chains and isolated B atoms. Ni12GaB8 is isotypical to the Al-compound (a=10.569(4), b=14.527(4) and c=14.557(5) ).

Relationship between the synthesis conditions and the structural, electrical, magnetic, and hydrogen absorption properties of the ternary compounds GdNi3X2 with X = Al, Ga, or Sn

The crystal structure of the ternary compounds GdNi3X2 (X = Al, Ga, or Sn) obtained by melting (M-sample) and subsequent annealing at 1273 K (A1-sample) or 1073 K (A2-sample) has been investigated by means of X-ray powder diffraction and transmission electron microscopy. GdNi3Sn2 crystallizes at all temperatures, in the hexagonal HoNi2.6Ga2.4-type. GdNi3Ga2 presents two varieties: the high-temperature form (M-sample) adopts the hexagonal CaCu5-type, whereas the HoNi2.6Ga2.4-type is observed for the A2-sample. The structural properties of GdNi3Al2 (M- and Al-samples) are more complicated; the electron diffraction patterns suggest the occurrence of a new super-structure of the hexagonal CaCu5-type. The study of the electrical and magnetic properties of these compounds shows that GdNi3Ga2 is ferromagnetic (T(C) = 18.0(5) K), GdNi3Sn2 orders antiferromagneticaily (T(N) = 19.5(5) K), and GdNi3Al2 (M- or Al-sample) presents a ferromagnetic behavior (T(C) = 20.0(5) K). Moreover, the hydrogen absorption properties of the Al-based intermetallic are dependent on its synthesis conditions. (C) 2000 Academic Press.

The nickel-rich part of the Ga-Ni phase diagram and the corresponding phase relations in the ternary Ga-Ni-Sb system

In the past years, metal/III-V compound semiconductor interfaces have been investigated intensively in order to find a suitable metallization scheme meeting the required performance, reproducibility and stability criteria. Equilibrium phase diagrams provide a base for understanding the interfacial reactions, hence solid state equilibria at 600 and 900°C in the Ga-Ni-Sb system have been experimentally determined and are presented in this article. In the course of the work the nickel-rich pan of the Ga-Ni phase diagram has been revised by means of DTA and the diffusion couple technique. This study was undertaken to clarify the true temperature range of stability for the compounds Ga2Ni3 and Ga9Ni13 that is of significant importance for establishing the Ga-Xi-Sb phase diagram. WILEY-VCH Verlag GmbH, 1998.