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Cubic gallium oxynitride is synthesized by solvothermal processing of a gallium ethylene diamine complex and H2O (autoclave, 200 °C, 1 d). [ABSTRACT FROM AUTHOR]

The specific locations of the anions—nitrogen and oxygen—in the crystallographic sites are not known in the spinel-type gallium oxonitride. We report here on an indirect method for determining the specific location of the light elements N and O in a defect spinel-structured gallium oxonitride, Ga2.79O3.05N0.76. The locations of elements that are adjacent in the periodic table (ΔZ=±1) are indistinguishable with conventional x-ray diffraction techniques. However, by examining the local electronic structure we show that the anions are spatially ordered such that R3m (no. 166) is the most appropriate defect-free space group. Finally, we determined the electronic band gap of Ga2.79O3.05N0.76 experimentally to be 2.95 ± 0.30, agreeing with our calculated value of 2.79 eV (direct) for Ga3O3N using a local density approximation functional including a semilocal potential modified from that of Becke and Johnson (the MBJLDA functional). [ABSTRACT FROM AUTHOR]

The structural and electronic properties of a spinel structure of Ga3NO3 are investigated. Comparison is made with zinc-blende and wurtzite GaN as well as with β-Ga2O3, all of which are important direct gap materials. It is suggested that spinel Ga3NO3 may be formed through an alloyed mixture of GaN and Ga2O3. Ga3NO3 is also predicted to be a direct gap material with a value lying close to its nitride counterparts. The calculated lattice constant of the spinel Ga3NO3 is in excellent agreement with the structure of a recently synthesized cubic gallium oxynitride phase with an identified elemental composition near Ga2.8N0.5O3.5. [Copyright &y& Elsevier]

The formation conditions of cubic spinel-structured gallium oxonitride have been investigated in situ under high-pressure/high-temperature conditions using a laser-heated diamond anvil cell. As starting materials, a mixture of the end members w-GaN/β-Ga2O3 in a molar ratio of 3:2 and a gallium oxonitride ceramic derived during pyrolysis from the metallo-organic precursor (Ga(OtBu)2NMe2)2 were used. In the mixture of the end members, spinel-structured gallium oxonitride starts crystallizing at a pressure of 3 GPa and at a temperature of about 1300 °C. The precursor-derived ceramic with predefined bondings reacted completely to the spinel phase, without by-products, at a pressure of 0.7 GPa. For the spinel-structured gallium oxonitride we determined a bulk modulus K of 216(7) GPa using a fixed value of 4 for K'. The spinel-structured gallium oxonitride exhibits a cell volume of 552.9(5) Å3 at ambient pressure. [ABSTRACT FROM AUTHOR]