Search NASA⌕ Search

SEARCH · Search NASA

Results for “MgGa”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Epitaxial growth and characterization of magnesium gallate (MgGa 2 O 4 ) thin films by pulsed laser deposition

To advance high power device application of MgGa 2 O 4 , it is imperative to achieve crystalline epitaxial thin films and to observe its materials’ characteristics within a wide range of growth conditions. However, there is no published work on the growth of this promising ultrawide bandgap material till this day. In this study, we report the crystalline growth of MgGa 2 O 4 thin films on c-plane (006) sapphire substrates using the pulsed laser deposition (PLD) technique in a broad range of temperature and oxygen pressure. The temperature range for this crystalline growth was within the temperature range of 300°C to 700°C and a pressure range of 1x10 -1 to 1x10 -3 Torr. Within this parameter range, the structural, chemical, optical, and surface property of MgGa 2 O 4 thin films have been investigated. Specifically, the acquired XRD patterns confirmed the film growth along the [111] preferential crystal orientation in the lattice. Here, the rocking curve measurement of the prominent (222) plane showed an increasing trend of the crystallinity with growth temperature and pressure. Furthermore, the XRD phi (φ) scan demonstrated the six-fold rotational symmetry of the MgGa 2 O 4 films and the epitaxial relationship of 30° between the film and the sapphire substrate. The XPS spectra confirmed the presence of +2 and +3 oxidation state for Mg and Ga respectively, in the films. The direct bandgap of MgGa 2 O 4 films was obtained ~5.27±0.03 eV by analyzing the UV-Vis absorbance spectra using the Tauc equation. The SEM images exhibited a granular surface morphology of the MgGa 2 O 4 films with an increasing trend in the grain size from low to high temperature and pressure. The refractive index and thickness of these films were in the range of ~1.90±0.02 and ~70±2.0 nm, respectively determined by fitting the spectroscopic ellipsometry data.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. Mg is bonded in a 6-coordinate geometry to seven equivalent Ga atoms. There are a spread of Mg–Ga bond distances ranging from 2.80–3.33 Å. Ga is bonded in a 10-coordinate geometry to seven equivalent Mg and three equivalent Ga atoms. There are two shorter (2.67 Å) and one longer (2.92 Å) Ga–Ga bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa is beta-prime cadmium gold structured and crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. Mg is bonded in a 8-coordinate geometry to eight equivalent Ga atoms. There are a spread of Mg–Ga bond distances ranging from 2.92–3.02 Å. Ga is bonded in a 8-coordinate geometry to eight equivalent Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded in a 12-coordinate geometry to six Ga atoms. There are two shorter (2.88 Å) and four longer (3.06 Å) Mg–Ga bond lengths. In the second Mg site, Mg is bonded in a 12-coordinate geometry to four Ga atoms. There are two shorter (2.84 Å) and two longer (3.00 Å) Mg–Ga bond lengths. In the third Mg site, Mg is bonded to four Ga atoms to form distorted edge-sharing MgGa4 cuboctahedra. There are two shorter (3.01 Å) and two longer (3.07 Å) Mg–Ga bond lengths. There are three inequivalent Ga sites. In the first Ga site, Ga is bonded in a 4-coordinate geometry to four Mg atoms. In the second Ga site, Ga is bonded in a 12-coordinate geometry to six Mg atoms. In the third Ga site, Ga is bonded in a 12-coordinate geometry to four Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa is Wurtzite structured and crystallizes in the hexagonal P6_3mc space group. The structure is three-dimensional. Mg is bonded to four equivalent Ga atoms to form corner-sharing MgGa4 tetrahedra. All Mg–Ga bond lengths are 2.74 Å. Ga is bonded to four equivalent Mg atoms to form corner-sharing GaMg4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to nine Mg and three equivalent Ga atoms to form distorted MgMg9Ga3 cuboctahedra that share corners with six equivalent GaGa12 cuboctahedra, corners with twelve equivalent MgMg9Ga3 cuboctahedra, edges with twelve MgMg9Ga3 cuboctahedra, a faceface with one GaGa12 cuboctahedra, and faces with thirteen MgMg9Ga3 cuboctahedra. There are six shorter (3.07 Å) and three longer (3.20 Å) Mg–Mg bond lengths. All Mg–Ga bond lengths are 3.01 Å. In the second Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with six equivalent MgMg12 cuboctahedra, edges with eighteen MgMg9Ga3 cuboctahedra, and faces with eighteen MgMg9Ga3 cuboctahedra. All Mg–Mg bond lengths are 3.07 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded to twelve Ga atoms to form GaGa12 cuboctahedra that share corners with six equivalent GaGa12 cuboctahedra, corners with twelve equivalent MgMg9Ga3 cuboctahedra, edges with six equivalent GaGa12 cuboctahedra, faces with two equivalent MgMg9Ga3 cuboctahedra, and faces with six equivalent GaGa12 cuboctahedra. There are six shorter (3.07 Å) and six longer (3.12 Å) Ga–Ga bond lengths. In the second Ga site, Ga is bonded in a 12-coordinate geometry to three equivalent Mg and three equivalent Ga atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa is Tetraauricupride structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Mg is bonded in a body-centered cubic geometry to eight equivalent Ga atoms. All Mg–Ga bond lengths are 2.91 Å. Ga is bonded in a body-centered cubic geometry to eight equivalent Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to four equivalent Mg and eight Ga atoms to form distorted MgMg4Ga8 cuboctahedra that share corners with six equivalent MgMg4Ga8 cuboctahedra, edges with fourteen MgMg4Ga8 cuboctahedra, and faces with eight equivalent MgMg5Ga7 cuboctahedra. There are two shorter (3.04 Å) and two longer (3.06 Å) Mg–Mg bond lengths. There are a spread of Mg–Ga bond distances ranging from 2.93–3.08 Å. In the second Mg site, Mg is bonded to five Mg and seven Ga atoms to form distorted MgMg5Ga7 cuboctahedra that share corners with twelve equivalent MgMg5Ga7 cuboctahedra, edges with ten MgMg4Ga8 cuboctahedra, and faces with eight MgMg4Ga8 cuboctahedra. There are one shorter (3.03 Å) and two longer (3.07 Å) Mg–Mg bond lengths. There are a spread of Mg–Ga bond distances ranging from 2.92–3.09 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded in a 12-coordinate geometry to seven Mg atoms. In the second Ga site, Ga is bonded in a 12-coordinate geometry to eight Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Mg is bonded to five equivalent Ga atoms to form a mixture of edge and corner-sharing MgGa5 trigonal bipyramids. There are two shorter (2.67 Å) and three longer (2.83 Å) Mg–Ga bond lengths. Ga is bonded to five equivalent Mg atoms to form a mixture of edge and corner-sharing GaMg5 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded to four Ga atoms to form distorted corner-sharing MgGa4 cuboctahedra. There are two shorter (2.98 Å) and two longer (3.04 Å) Mg–Ga bond lengths. In the second Mg site, Mg is bonded in a 12-coordinate geometry to eight Ga atoms. There are a spread of Mg–Ga bond distances ranging from 2.90–3.11 Å. In the third Mg site, Mg is bonded in a 12-coordinate geometry to six Ga atoms. There are a spread of Mg–Ga bond distances ranging from 2.93–3.05 Å. There are three inequivalent Ga sites. In the first Ga site, Ga is bonded in a 6-coordinate geometry to six Mg atoms. In the second Ga site, Ga is bonded in a 12-coordinate geometry to eight Mg atoms. In the third Ga site, Ga is bonded in a 4-coordinate geometry to four Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded in a 12-coordinate geometry to seven Ga atoms. There are a spread of Mg–Ga bond distances ranging from 2.91–3.08 Å. In the second Mg site, Mg is bonded in a 12-coordinate geometry to six Ga atoms. There are four shorter (2.98 Å) and two longer (3.16 Å) Mg–Ga bond lengths. In the third Mg site, Mg is bonded in a 12-coordinate geometry to five Ga atoms. There are one shorter (2.88 Å) and four longer (2.97 Å) Mg–Ga bond lengths. There are three inequivalent Ga sites. In the first Ga site, Ga is bonded in a 5-coordinate geometry to five Mg and four Ga atoms. There are two shorter (2.90 Å) and two longer (2.92 Å) Ga–Ga bond lengths. In the second Ga site, Ga is bonded in a 9-coordinate geometry to six Mg and three Ga atoms. The Ga–Ga bond length is 2.80 Å. In the third Ga site, Ga is bonded in a 10-coordinate geometry to seven Mg and three Ga atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(MgGa)2 by Materials Project

Eu(MgGa)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Mg is bonded to four equivalent Ga atoms to form MgGa4 tetrahedra that share corners with eight equivalent EuGa8 hexagonal bipyramids, corners with four equivalent MgGa4 tetrahedra, edges with four equivalent EuGa8 hexagonal bipyramids, and edges with four equivalent MgGa4 tetrahedra. All Mg–Ga bond lengths are 2.81 Å. Eu is bonded to eight equivalent Ga atoms to form distorted EuGa8 hexagonal bipyramids that share corners with sixteen equivalent MgGa4 tetrahedra, edges with four equivalent EuGa8 hexagonal bipyramids, edges with eight equivalent MgGa4 tetrahedra, and faces with four equivalent EuGa8 hexagonal bipyramids. All Eu–Ga bond lengths are 3.42 Å. Ga is bonded in a 9-coordinate geometry to four equivalent Mg, four equivalent Eu, and one Ga atom. The Ga–Ga bond length is 2.50 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa is alpha-derived structured and crystallizes in the orthorhombic Pmmn space group. The structure is three-dimensional. Mg is bonded in a 6-coordinate geometry to six equivalent Ga atoms. There are a spread of Mg–Ga bond distances ranging from 2.87–3.01 Å. Ga is bonded in a 6-coordinate geometry to six equivalent Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent Mg and eight Ga atoms to form a mixture of distorted edge, corner, and face-sharing MgMg2Ga8 cuboctahedra. Both Mg–Mg bond lengths are 3.06 Å. There are a spread of Mg–Ga bond distances ranging from 2.91–3.06 Å. In the second Mg site, Mg is bonded to two equivalent Mg and eight Ga atoms to form a mixture of distorted edge, corner, and face-sharing MgMg2Ga8 cuboctahedra. Both Mg–Mg bond lengths are 3.07 Å. There are a spread of Mg–Ga bond distances ranging from 2.88–3.06 Å. In the third Mg site, Mg is bonded to six Mg and six Ga atoms to form a mixture of distorted edge, corner, and face-sharing MgMg6Ga6 cuboctahedra. Both Mg–Mg bond lengths are 3.10 Å. There are two shorter (2.98 Å) and four longer (3.06 Å) Mg–Ga bond lengths. There are three inequivalent Ga sites. In the first Ga site, Ga is bonded in a 12-coordinate geometry to eight Mg and four Ga atoms. There are two shorter (2.96 Å) and two longer (3.10 Å) Ga–Ga bond lengths. In the second Ga site, Ga is bonded in a 12-coordinate geometry to six Mg and two equivalent Ga atoms. In the third Ga site, Ga is bonded in a 12-coordinate geometry to eight Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa is Zincblende, Sphalerite structured and crystallizes in the cubic F-43m space group. The structure is three-dimensional. Mg is bonded to four equivalent Ga atoms to form corner-sharing MgGa4 tetrahedra. All Mg–Ga bond lengths are 2.72 Å. Ga is bonded to four equivalent Mg atoms to form corner-sharing GaMg4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Mg is bonded to six equivalent Ga atoms to form a mixture of distorted corner, edge, and face-sharing MgGa6 cuboctahedra. All Mg–Ga bond lengths are 2.96 Å. Ga is bonded in a 12-coordinate geometry to six equivalent Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa crystallizes in the trigonal P3m1 space group. The structure is three-dimensional. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded to three equivalent Mg and three equivalent Ga atoms to form distorted MgMg3Ga3 cuboctahedra that share corners with six equivalent GaMg3Ga3 cuboctahedra, corners with twelve MgMg9Ga3 cuboctahedra, edges with twelve MgMg3Ga3 cuboctahedra, a faceface with one MgMg6Ga6 cuboctahedra, and a faceface with one GaMg3Ga3 cuboctahedra. All Mg–Mg bond lengths are 3.21 Å. All Mg–Ga bond lengths are 3.00 Å. In the second Mg site, Mg is bonded to nine Mg and three equivalent Ga atoms to form distorted MgMg9Ga3 cuboctahedra that share corners with twelve MgMg3Ga3 cuboctahedra, corners with eighteen GaMg6 cuboctahedra, edges with six equivalent GaMg3Ga3 cuboctahedra, edges with twelve MgMg3Ga3 cuboctahedra, faces with two GaMg6 cuboctahedra, and faces with six equivalent MgMg9Ga3 cuboctahedra. All Mg–Mg bond lengths are 3.06 Å. All Mg–Ga bond lengths are 3.02 Å. In the third Mg site, Mg is bonded to six equivalent Mg and six Ga atoms to form distorted MgMg6Ga6 cuboctahedra that share corners with twelve MgMg3Ga3 cuboctahedra, corners with twelve GaMg6 cuboctahedra, edges with six equivalent MgMg6Ga6 cuboctahedra, edges with twelve GaMg6 cuboctahedra, faces with seven MgMg3Ga3 cuboctahedra, and faces with seven GaMg3Ga3 cuboctahedra. All Mg–Mg bond lengths are 3.06 Å. There are three shorter (3.03 Å) and three longer (3.10 Å) Mg–Ga bond lengths. There are three inequivalent Ga sites. In the first Ga site, Ga is bonded to six Mg atoms to form distorted GaMg6 cuboctahedra that share corners with six equivalent GaMg3Ga9 cuboctahedra, corners with twelve MgMg9Ga3 cuboctahedra, edges with six equivalent MgMg6Ga6 cuboctahedra, edges with six equivalent GaMg6 cuboctahedra, a faceface with one MgMg9Ga3 cuboctahedra, and a faceface with one GaMg3Ga9 cuboctahedra. In the second Ga site, Ga is bonded to three equivalent Mg and three equivalent Ga atoms to form distorted GaMg3Ga3 cuboctahedra that share corners with six equivalent GaMg3Ga9 cuboctahedra, corners with eighteen MgMg3Ga3 cuboctahedra, edges with six equivalent MgMg9Ga3 cuboctahedra, edges with twelve GaMg3Ga3 cuboctahedra, and faces with two MgMg3Ga3 cuboctahedra. All Ga–Ga bond lengths are 3.02 Å. In the third Ga site, Ga is bonded to three equivalent Mg and nine Ga atoms to form distorted GaMg3Ga9 cuboctahedra that share corners with six equivalent MgMg9Ga3 cuboctahedra, corners with eighteen GaMg6 cuboctahedra, edges with six equivalent MgMg6Ga6 cuboctahedra, edges with twelve GaMg3Ga3 cuboctahedra, faces with seven MgMg9Ga3 cuboctahedra, and faces with seven GaMg6 cuboctahedra. All Ga–Ga bond lengths are 3.06 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgGa by Materials Project

MgGa crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Mg is bonded to six equivalent Ga atoms to form a mixture of distorted edge and corner-sharing MgGa6 cuboctahedra. All Mg–Ga bond lengths are 2.97 Å. Ga is bonded in a 6-coordinate geometry to six equivalent Mg atoms.

36 MATERIALS SCIENCE↗