Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Ba-Hf-Mg”

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.

Materials Data on BaHfMg2 by Materials Project

BaMg2Hf crystallizes in the cubic F-43m space group. The structure is three-dimensional. Ba is bonded in a distorted body-centered cubic geometry to ten Mg and four equivalent Hf atoms. There are four shorter (3.35 Å) and six longer (3.87 Å) Ba–Mg bond lengths. All Ba–Hf bond lengths are 3.35 Å. There are two inequivalent Mg sites. In the first Mg site, Mg is bonded in a 8-coordinate geometry to six equivalent Ba, four equivalent Mg, and four equivalent Hf atoms. All Mg–Mg bond lengths are 3.35 Å. All Mg–Hf bond lengths are 3.35 Å. In the second Mg site, Mg is bonded in a distorted body-centered cubic geometry to four equivalent Ba and four equivalent Mg atoms. Hf is bonded in a distorted body-centered cubic geometry to four equivalent Ba and four equivalent Mg atoms.

36 MATERIALS SCIENCE↗

Materials Data on BaHfMg6 by Materials Project

BaMg6Hf crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Ba is bonded to ten Mg and two equivalent Hf atoms to form BaHf2Mg10 cuboctahedra that share corners with four equivalent MgBa2Mg10 cuboctahedra, corners with six equivalent BaHf2Mg10 cuboctahedra, edges with two equivalent MgBa2Mg10 cuboctahedra, edges with four equivalent HfBa2Mg10 cuboctahedra, faces with two equivalent BaHf2Mg10 cuboctahedra, faces with two equivalent HfBa2Mg10 cuboctahedra, and faces with eight MgBa2Mg10 cuboctahedra. There are a spread of Ba–Mg bond distances ranging from 3.30–3.44 Å. Both Ba–Hf bond lengths are 3.40 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Ba, seven Mg, and two equivalent Hf atoms. There are a spread of Mg–Mg bond distances ranging from 3.16–3.41 Å. Both Mg–Hf bond lengths are 3.22 Å. In the second Mg site, Mg is bonded to two equivalent Ba and ten Mg atoms to form distorted MgBa2Mg10 cuboctahedra that share corners with four equivalent BaHf2Mg10 cuboctahedra, corners with six equivalent MgBa2Mg10 cuboctahedra, edges with two equivalent BaHf2Mg10 cuboctahedra, edges with four equivalent MgHf2Mg10 cuboctahedra, faces with two equivalent BaHf2Mg10 cuboctahedra, faces with four MgBa2Mg10 cuboctahedra, and faces with six equivalent HfBa2Mg10 cuboctahedra. There are four shorter (3.29 Å) and two longer (3.34 Å) Mg–Mg bond lengths. In the third Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Ba, eight Mg, and two equivalent Hf atoms. There are a spread of Mg–Mg bond distances ranging from 3.20–3.53 Å. There are one shorter (3.15 Å) and one longer (3.58 Å) Mg–Hf bond lengths. In the fourth Mg site, Mg is bonded to ten Mg and two equivalent Hf atoms to form MgHf2Mg10 cuboctahedra that share corners with four equivalent HfBa2Mg10 cuboctahedra, corners with six equivalent MgHf2Mg10 cuboctahedra, edges with two equivalent HfBa2Mg10 cuboctahedra, edges with four equivalent MgBa2Mg10 cuboctahedra, faces with two equivalent HfBa2Mg10 cuboctahedra, faces with four MgBa2Mg10 cuboctahedra, and faces with six equivalent BaHf2Mg10 cuboctahedra. Both Mg–Hf bond lengths are 3.37 Å. Hf is bonded to two equivalent Ba and ten Mg atoms to form distorted HfBa2Mg10 cuboctahedra that share corners with four equivalent MgHf2Mg10 cuboctahedra, corners with six equivalent HfBa2Mg10 cuboctahedra, edges with two equivalent MgHf2Mg10 cuboctahedra, edges with four equivalent BaHf2Mg10 cuboctahedra, faces with two equivalent BaHf2Mg10 cuboctahedra, faces with two equivalent HfBa2Mg10 cuboctahedra, and faces with eight MgBa2Mg10 cuboctahedra.

36 MATERIALS SCIENCE↗

Materials Data on BaHfMg6 by Materials Project

BaMg6Hf crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Ba is bonded to twelve Mg atoms to form BaMg12 cuboctahedra that share corners with four equivalent BaMg12 cuboctahedra, corners with eight equivalent HfMg12 cuboctahedra, edges with eight equivalent MgBa2Hf2Mg8 cuboctahedra, faces with two equivalent BaMg12 cuboctahedra, faces with four equivalent MgBa2Hf2Mg8 cuboctahedra, and faces with four equivalent HfMg12 cuboctahedra. There are a spread of Ba–Mg bond distances ranging from 3.35–3.57 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent Ba, eight Mg, and two equivalent Hf atoms to form distorted MgBa2Hf2Mg8 cuboctahedra that share corners with twelve equivalent MgBa2Hf2Mg8 cuboctahedra, edges with four equivalent BaMg12 cuboctahedra, edges with four equivalent HfMg12 cuboctahedra, faces with two equivalent BaMg12 cuboctahedra, faces with two equivalent HfMg12 cuboctahedra, and faces with six equivalent MgBa2Hf2Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.34–3.39 Å. There are one shorter (3.34 Å) and one longer (3.36 Å) Mg–Hf bond lengths. In the second Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Ba, six Mg, and two equivalent Hf atoms. There are one shorter (2.97 Å) and one longer (2.98 Å) Mg–Mg bond lengths. Both Mg–Hf bond lengths are 3.16 Å. In the third Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Ba, six Mg, and two equivalent Hf atoms. Both Mg–Hf bond lengths are 3.19 Å. In the fourth Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Ba, six Mg, and two equivalent Hf atoms. Both Mg–Hf bond lengths are 3.20 Å. Hf is bonded to twelve Mg atoms to form HfMg12 cuboctahedra that share corners with four equivalent HfMg12 cuboctahedra, corners with eight equivalent BaMg12 cuboctahedra, edges with eight equivalent MgBa2Hf2Mg8 cuboctahedra, faces with two equivalent HfMg12 cuboctahedra, faces with four equivalent BaMg12 cuboctahedra, and faces with four equivalent MgBa2Hf2Mg8 cuboctahedra.

36 MATERIALS SCIENCE↗