Search NASA⌕ Search

SEARCH · Search NASA

Results for “Ba-Mg-Si”

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.

7 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Ba2Mg3Si4 by Materials Project

Ba2Mg3Si4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Ba sites. In the first Ba site, Ba is bonded in a 7-coordinate geometry to five Mg and nine Si atoms. There are a spread of Ba–Mg bond distances ranging from 3.45–3.83 Å. There are a spread of Ba–Si bond distances ranging from 3.41–3.53 Å. In the second Ba site, Ba is bonded in a 8-coordinate geometry to eight Mg and eight Si atoms. There are a spread of Ba–Mg bond distances ranging from 3.60–3.73 Å. There are a spread of Ba–Si bond distances ranging from 3.43–3.58 Å. There are three inequivalent Mg sites. In the first Mg site, Mg is bonded to four Ba and four Si atoms to form a mixture of corner, edge, and face-sharing MgBa4Si4 tetrahedra. There are three shorter (2.77 Å) and one longer (2.80 Å) Mg–Si bond lengths. In the second Mg site, Mg is bonded in a 12-coordinate geometry to five Ba and five Si atoms. There are a spread of Mg–Si bond distances ranging from 2.74–2.88 Å. In the third Mg site, Mg is bonded to four equivalent Ba and four Si atoms to form a mixture of distorted corner, edge, and face-sharing MgBa4Si4 tetrahedra. There are a spread of Mg–Si bond distances ranging from 2.78–2.81 Å. There are four inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to four Ba, four Mg, and one Si atom. The Si–Si bond length is 2.44 Å. In the second Si site, Si is bonded in a 9-coordinate geometry to five equivalent Ba, two equivalent Mg, and two Si atoms. There are one shorter (2.42 Å) and one longer (2.44 Å) Si–Si bond lengths. In the third Si site, Si is bonded in a 9-coordinate geometry to four equivalent Ba, four Mg, and one Si atom. The Si–Si bond length is 2.50 Å. In the fourth Si site, Si is bonded in a 9-coordinate geometry to four Ba, three Mg, and two Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ba5Mg18Si13 by Materials Project

Ba5Mg18Si13 crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. there are two inequivalent Ba sites. In the first Ba site, Ba is bonded in a 8-coordinate geometry to eight Mg and eight Si atoms. There are a spread of Ba–Mg bond distances ranging from 3.55–3.84 Å. There are a spread of Ba–Si bond distances ranging from 3.38–3.57 Å. In the second Ba site, Ba is bonded in a 6-coordinate geometry to nine Mg and six equivalent Si atoms. There are six shorter (3.67 Å) and three longer (3.71 Å) Ba–Mg bond lengths. All Ba–Si bond lengths are 3.46 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to three Ba and four Si atoms to form distorted MgBa3Si4 tetrahedra that share corners with nine MgBa3Si4 tetrahedra, edges with six MgBa3Si4 tetrahedra, and faces with five MgBa2Si4 tetrahedra. There are a spread of Mg–Si bond distances ranging from 2.75–2.83 Å. In the second Mg site, Mg is bonded to two equivalent Ba and four Si atoms to form a mixture of distorted face, edge, and corner-sharing MgBa2Si4 tetrahedra. There are two shorter (2.68 Å) and two longer (2.78 Å) Mg–Si bond lengths. In the third Mg site, Mg is bonded to three Ba and four Si atoms to form a mixture of distorted face, edge, and corner-sharing MgBa3Si4 tetrahedra. There are a spread of Mg–Si bond distances ranging from 2.77–2.83 Å. In the fourth Mg site, Mg is bonded in a distorted single-bond geometry to five Si atoms. There are one shorter (2.73 Å) and four longer (3.16 Å) Mg–Si bond lengths. There are four inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to two equivalent Ba and seven Mg atoms. In the second Si site, Si is bonded in a 9-coordinate geometry to two equivalent Ba and seven Mg atoms. In the third Si site, Si is bonded in a 9-coordinate geometry to six equivalent Ba and three equivalent Si atoms. All Si–Si bond lengths are 2.42 Å. In the fourth Si site, Si is bonded in a 9-coordinate geometry to four equivalent Ba, four Mg, and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ba(MgSi)2 by Materials Project

BaMg2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ba is bonded in a 8-coordinate geometry to eight equivalent Mg and eight equivalent Si atoms. All Ba–Mg bond lengths are 3.62 Å. All Ba–Si bond lengths are 3.53 Å. Mg is bonded to four equivalent Ba and four equivalent Si atoms to form a mixture of distorted edge, face, and corner-sharing MgBa4Si4 tetrahedra. All Mg–Si bond lengths are 2.79 Å. Si is bonded in a 9-coordinate geometry to four equivalent Ba, four equivalent Mg, and one Si atom. The Si–Si bond length is 2.48 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BaMgSi by Materials Project

BaMgSi is Matlockite structured and crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ba2+ is bonded to five equivalent Si4- atoms to form distorted BaSi5 trigonal bipyramids that share corners with twelve equivalent MgSi4 tetrahedra, corners with four equivalent BaSi5 trigonal bipyramids, edges with four equivalent MgSi4 tetrahedra, and edges with eight equivalent BaSi5 trigonal bipyramids. There are four shorter (3.46 Å) and one longer (3.63 Å) Ba–Si bond lengths. Mg2+ is bonded to four equivalent Si4- atoms to form MgSi4 tetrahedra that share corners with four equivalent MgSi4 tetrahedra, corners with twelve equivalent BaSi5 trigonal bipyramids, edges with four equivalent MgSi4 tetrahedra, and edges with four equivalent BaSi5 trigonal bipyramids. All Mg–Si bond lengths are 2.83 Å. Si4- is bonded in a 9-coordinate geometry to five equivalent Ba2+ and four equivalent Mg2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BaMgSi by Materials Project

BaMgSi crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ba2+ is bonded to five equivalent Si4- atoms to form distorted BaSi5 trigonal bipyramids that share corners with eight equivalent MgSi4 tetrahedra, corners with eight equivalent BaSi5 trigonal bipyramids, edges with six equivalent MgSi4 tetrahedra, and edges with six equivalent BaSi5 trigonal bipyramids. There are a spread of Ba–Si bond distances ranging from 3.39–3.55 Å. Mg2+ is bonded to four equivalent Si4- atoms to form MgSi4 tetrahedra that share corners with eight equivalent MgSi4 tetrahedra, corners with eight equivalent BaSi5 trigonal bipyramids, edges with two equivalent MgSi4 tetrahedra, and edges with six equivalent BaSi5 trigonal bipyramids. There are a spread of Mg–Si bond distances ranging from 2.84–3.14 Å. Si4- is bonded in a 9-coordinate geometry to five equivalent Ba2+ and four equivalent Mg2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BaMg4Si3 by Materials Project

BaMg4Si3 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ba is bonded in a 8-coordinate geometry to eight equivalent Mg and eight equivalent Si atoms. All Ba–Mg bond lengths are 3.58 Å. All Ba–Si bond lengths are 3.49 Å. Mg is bonded to two equivalent Ba and four Si atoms to form a mixture of distorted edge, corner, and face-sharing MgBa2Si4 tetrahedra. There are two shorter (2.76 Å) and two longer (2.80 Å) Mg–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded in a body-centered cubic geometry to eight equivalent Mg atoms. In the second Si site, Si is bonded in a 9-coordinate geometry to four equivalent Ba, four equivalent Mg, and one Si atom. The Si–Si bond length is 2.46 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BaMg6Si by Materials Project

BaMg6Si crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Ba is bonded to ten Mg and two equivalent Si atoms to form a mixture of distorted corner and face-sharing BaMg10Si2 cuboctahedra. There are a spread of Ba–Mg bond distances ranging from 3.43–3.73 Å. Both Ba–Si bond lengths are 3.42 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 1-coordinate geometry to two equivalent Ba, two equivalent Mg, and one Si atom. Both Mg–Mg bond lengths are 3.09 Å. The Mg–Si bond length is 2.78 Å. In the second Mg site, Mg is bonded in a 6-coordinate geometry to six Mg atoms. There are two shorter (3.25 Å) and four longer (3.33 Å) Mg–Mg bond lengths. In the third Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent Ba, three Mg, and two equivalent Si atoms. The Mg–Mg bond length is 3.37 Å. Both Mg–Si bond lengths are 2.98 Å. In the fourth Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Ba and eight Mg atoms. Si is bonded in a 8-coordinate geometry to two equivalent Ba and six Mg atoms.

36 MATERIALS SCIENCE↗