Gallium phases, synthesis

Gu Z, Parans Paranthaman M, Pan Z (2009) Vapor-phase synthesis of gallium phosphide nanowires. Cryst Growth Des 9 525-527... 

Liquid injection molding, for silicone rubbers, 3, 674—675 Liquid ligands, in metal vapor synthesis, 1, 229 Liquid-phase catalysis, supported, for green olefin hydroformylation, 12, 855 Lithiacarbaboranes, preparation, 3, 114 Lithiation, arene chromium tricarbonyls, 5, 236 Lithium aluminum amides, reactions, 3, 282 Lithium aluminum hydride, for alcohol reductions, 3, 279 Lithium borohydride, in hydroborations, 9, 158 Lithium gallium hydride, in reduction reactions, 9, 738 Lithium indium hydride, in carbonyl reductions, 9, 713—714... 

Ohare et al. (1998) Aluminum phosphates Gallium fluorophosphates Formation of mesoporous structure, intermediate phases + n.a. Synthesis optimization... 

The presence of a stable diborane-like molecule [H2Ga(/x-H)]2 in both solution and the vapor phase suggests that the chemistry of gallane has a marked similarity to that of diborane, that is, (1). The analogy between the gallium and boron hydrides is extended by the synthesis and structural characterization of the mixed gallaborane, GaBHe (1). 

The crystallinity and phase purity were examined by XRD. The XRD patterns of all samples resemble those of pentasil-type zeolites with respect to position and intensity of reflexes. No other crystalline by-products could be detected within the experimental accuracy of the method. The narrow peaks and their high intensity reflect the good crystallinity of the samples. The chemical analysis reveals that the amount of gallium present is the same as in the starting synthesis mixture. As not all silica is incorporated into the zeolite the Si/Ga ratio of the samples is finally smaller than that of the recipe. 

The NbjGa phase was first determined to be superconducting by Matthias et al. [86]. Nb Ga adopts the cubic [Cr Si] A15 structure (Fig. 2-5) with an a-axis spacing from 5.16 to 5.18 A. The CVD synthesis of superconducting Nb Ga films by hydrogen reduction of mixed niobium and gallium metal chlorides has been reported [87]. One phase-pure A15 Nb. Ga film had 7(. = 18 K while a mixed phase Nb Ga/Nb Gai deposit exhi-bitied T, = 20,3 K. 

The stoichiometric compound of gallium and oxygen, Ga203, exists in a wide variety of polymorphic phases, including a, p, y, b, e, and 0 phases that so far have heen identified using powder X-ray diffraction (XRD) [72]. The polymorphs a and p are usually prepared at ambient pressure from thermal decomposition of the nitrate (Ga(N03)3), or via sol-gel synthesis routes followed hy dehydration and recrystal-lization of the gel (Figure 3.3 adapted from [72]). 

Figure 3.3 Phase transformations and synthesis temperatures in the gallium oxide system. Adapted from Roy et at. [72],...

During the past thirty years several reports have been published on the synthesis of gallium oxonitride phases. The first of these was mentioned by Verdier and Marchand in 1976 as a side product during the reaction of ammonia with gallium oxide, whenaphase with the composition Gai x 3nxpNi xO withx 0.1 and as vacancies was isolated under low-temperature conditions [213]. The authors did not report any detailed crystal structure data, but did note that the XRD pattern was... 

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