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At least 325 records · Page 18
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DOE OSTI2020

Materials Data on Hf3(CrGa3)2 by Materials Project

Hf3(CrGa3)2 crystallizes in the orthorhombic Pmmn space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 11-coordinate geometry to two equivalent Cr and nine Ga atoms. Both Hf–Cr bond lengths are 2.99 Å. There are a spread of Hf–Ga bond distances ranging from 2.81–3.02 Å. In the second Hf site, Hf is bonded in a 7-coordinate geometry to four equivalent Cr and seven Ga atoms. All Hf–Cr bond lengths are 3.05 Å. There are a spread of Hf–Ga bond distances ranging from 2.69–2.91 Å. Cr is bonded to four Hf, two equivalent Cr, and six Ga atoms to form a mixture of distorted face, edge, and corner-sharing CrHf4Cr2Ga6 cuboctahedra. Both Cr–Cr bond lengths are 2.66 Å. There are a spread of Cr–Ga bond distances ranging from 2.51–2.76 Å. There are four inequivalent Ga sites. In the first Ga site, Ga is bonded in a 5-coordinate geometry to four Hf, two equivalent Cr, and two equivalent Ga atoms. Both Ga–Ga bond lengths are 2.62 Å. In the second Ga site, Ga is bonded in a 1-coordinate geometry to three Hf, four equivalent Cr, and two equivalent Ga atoms. Both Ga–Ga bond lengths are 2.83 Å. In the third Ga site, Ga is bonded in a 12-coordinate geometry to four Hf and four equivalent Cr atoms. In the fourth Ga site, Ga is bonded in a 10-coordinate geometry to five Hf and five Ga atoms. There are one shorter (2.55 Å) and one longer (2.77 Å) Ga–Ga bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf2Mn by Materials Project

Hf2Mn crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 6-coordinate geometry to six equivalent Hf and six equivalent Mn atoms. All Hf–Hf bond lengths are 3.08 Å. All Hf–Mn bond lengths are 2.61 Å. In the second Hf site, Hf is bonded in a 2-coordinate geometry to ten Hf and four equivalent Mn atoms. There are four shorter (3.17 Å) and four longer (3.21 Å) Hf–Hf bond lengths. There are two shorter (2.81 Å) and two longer (3.07 Å) Hf–Mn bond lengths. Mn is bonded in a 12-coordinate geometry to nine Hf and three equivalent Mn atoms. All Mn–Mn bond lengths are 2.89 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf5Sc5Ge6 by Materials Project

Sc5Hf5Ge6 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent Sc sites. In the first Sc site, Sc is bonded in a 5-coordinate geometry to five Ge atoms. There are a spread of Sc–Ge bond distances ranging from 2.72–3.06 Å. In the second Sc site, Sc is bonded in a 6-coordinate geometry to six Ge atoms. There are three shorter (2.83 Å) and three longer (2.84 Å) Sc–Ge bond lengths. There are three inequivalent Hf sites. In the first Hf site, Hf is bonded in a 5-coordinate geometry to five Ge atoms. There are a spread of Hf–Ge bond distances ranging from 2.72–3.06 Å. In the second Hf site, Hf is bonded in a 5-coordinate geometry to five Ge atoms. There are a spread of Hf–Ge bond distances ranging from 2.72–3.06 Å. In the third Hf site, Hf is bonded in a 5-coordinate geometry to five Ge atoms. There are a spread of Hf–Ge bond distances ranging from 2.72–3.06 Å. There are four inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent Sc and five Hf atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six Sc and three Hf atoms. In the third Ge site, Ge is bonded in a 9-coordinate geometry to five Sc and four Hf atoms. In the fourth Ge site, Ge is bonded in a 9-coordinate geometry to five Sc and four Hf atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf4NiRh by Materials Project

Hf4RhNi crystallizes in the cubic F-43m space group. The structure is three-dimensional. there are three inequivalent Hf sites. In the first Hf site, Hf is bonded in a 6-coordinate geometry to three equivalent Rh and three equivalent Ni atoms. All Hf–Rh bond lengths are 2.91 Å. All Hf–Ni bond lengths are 2.61 Å. In the second Hf site, Hf is bonded in a 2-coordinate geometry to two equivalent Rh atoms. Both Hf–Rh bond lengths are 2.86 Å. In the third Hf site, Hf is bonded in a 2-coordinate geometry to two equivalent Rh and two equivalent Ni atoms. Both Hf–Rh bond lengths are 3.04 Å. Both Hf–Ni bond lengths are 2.57 Å. Rh is bonded in a 12-coordinate geometry to nine Hf atoms. Ni is bonded in a 6-coordinate geometry to six Hf atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf10SiMo3 by Materials Project

Hf10Mo3Si crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are three inequivalent Hf sites. In the first Hf site, Hf is bonded in a 2-coordinate geometry to three equivalent Mo and one Si atom. There are one shorter (2.90 Å) and two longer (3.18 Å) Hf–Mo bond lengths. The Hf–Si bond length is 2.69 Å. In the second Hf site, Hf is bonded in a 3-coordinate geometry to two equivalent Mo and one Si atom. Both Hf–Mo bond lengths are 2.87 Å. The Hf–Si bond length is 3.09 Å. In the third Hf site, Hf is bonded in a 6-coordinate geometry to six equivalent Mo atoms. All Hf–Mo bond lengths are 2.79 Å. Mo is bonded in a 12-coordinate geometry to ten Hf and two equivalent Mo atoms. Both Mo–Mo bond lengths are 2.98 Å. Si is bonded in a 9-coordinate geometry to nine Hf atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf3(VGa3)2 by Materials Project

Hf3(VGa3)2 crystallizes in the orthorhombic Pmmn space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 11-coordinate geometry to two equivalent V and nine Ga atoms. Both Hf–V bond lengths are 3.02 Å. There are a spread of Hf–Ga bond distances ranging from 2.84–3.02 Å. In the second Hf site, Hf is bonded in a 7-coordinate geometry to four equivalent V and seven Ga atoms. All Hf–V bond lengths are 3.09 Å. There are a spread of Hf–Ga bond distances ranging from 2.74–2.94 Å. V is bonded to four Hf, two equivalent V, and six Ga atoms to form a mixture of distorted edge, face, and corner-sharing VHf4V2Ga6 cuboctahedra. Both V–V bond lengths are 2.69 Å. There are a spread of V–Ga bond distances ranging from 2.56–2.79 Å. There are four inequivalent Ga sites. In the first Ga site, Ga is bonded in a 8-coordinate geometry to four Hf, two equivalent V, and two equivalent Ga atoms. Both Ga–Ga bond lengths are 2.63 Å. In the second Ga site, Ga is bonded in a 1-coordinate geometry to three Hf, four equivalent V, and two equivalent Ga atoms. Both Ga–Ga bond lengths are 2.85 Å. In the third Ga site, Ga is bonded in a 12-coordinate geometry to four Hf and four equivalent V atoms. In the fourth Ga site, Ga is bonded in a 10-coordinate geometry to five Hf and five Ga atoms. There are one shorter (2.58 Å) and one longer (2.80 Å) Ga–Ga bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf3ScSi4 by Materials Project

ScHf3Si4 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. Sc is bonded in a 7-coordinate geometry to seven Si atoms. There are a spread of Sc–Si bond distances ranging from 2.72–2.94 Å. There are three inequivalent Hf sites. In the first Hf site, Hf is bonded in a 7-coordinate geometry to seven Si atoms. There are a spread of Hf–Si bond distances ranging from 2.72–2.91 Å. In the second Hf site, Hf is bonded in a 7-coordinate geometry to seven Si atoms. There are a spread of Hf–Si bond distances ranging from 2.70–2.91 Å. In the third Hf site, Hf is bonded in a 7-coordinate geometry to seven Si atoms. There are a spread of Hf–Si bond distances ranging from 2.72–2.93 Å. There are four inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to two equivalent Sc, five Hf, and two equivalent Si atoms. Both Si–Si bond lengths are 2.45 Å. In the second Si site, Si is bonded in a 9-coordinate geometry to one Sc, six Hf, and two equivalent Si atoms. Both Si–Si bond lengths are 2.45 Å. In the third Si site, Si is bonded in a 9-coordinate geometry to two equivalent Sc, five Hf, and two equivalent Si atoms. In the fourth Si site, Si is bonded in a 9-coordinate geometry to two equivalent Sc, five Hf, and two equivalent Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Multi-phase equation of state of ultrapure hafnium to 120 GPa

Hafnium (Hf) is an industrially important material due to its large neutron absorption cross-section and its high corrosion resistance. When subjected to high pressure, Hf phase transforms from its hexagonal close packed α-Hf phase to the hexagonal ω-Hf phase. Upon further compression, ω-Hf phase transforms to the body centered cubic β-Hf phase. In this study, the high pressure phase transformations of Hf are studied by compressing and decompressing a well-characterized Hf sample in diamond anvil cells up to 120 GPa while collecting x-ray diffraction data. The phase transformations of Hf were compared in both a He pressure transmitting medium (PTM) and no PTM over several experiments. It was found that the α-Hf to ω-Hf phase transition occurs at a higher pressure during compression and lower pressure during decompression with a helium (He) PTM compared to using no PTM. Finally, there was little difference in the ω-Hf to β-Hf phase transition pressure between the He PTM and no PTM. The equation of state was fit for all three phases of Hf and under both PTM and no-PTM.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2020

Materials Data on Hf2CuGe4 by Materials Project

CuGe4Hf2 is Parent of FeAs superconductors-derived structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded to four equivalent Cu and eight Ge atoms to form distorted HfCu4Ge8 cuboctahedra that share corners with four equivalent HfCu4Ge8 cuboctahedra, edges with four equivalent HfCu4Ge8 cuboctahedra, edges with eight equivalent CuHf4Cu4Ge4 cuboctahedra, faces with four equivalent HfCu4Ge8 cuboctahedra, and faces with four equivalent CuHf4Cu4Ge4 cuboctahedra. There are two shorter (3.05 Å) and two longer (3.07 Å) Hf–Cu bond lengths. There are four shorter (2.80 Å) and four longer (2.87 Å) Hf–Ge bond lengths. In the second Hf site, Hf is bonded in a 10-coordinate geometry to ten Ge atoms. There are a spread of Hf–Ge bond distances ranging from 2.77–3.14 Å. Cu is bonded to four equivalent Hf, four equivalent Cu, and four equivalent Ge atoms to form distorted CuHf4Cu4Ge4 cuboctahedra that share corners with four equivalent CuHf4Cu4Ge4 cuboctahedra, edges with eight equivalent HfCu4Ge8 cuboctahedra, faces with four equivalent HfCu4Ge8 cuboctahedra, and faces with eight equivalent CuHf4Cu4Ge4 cuboctahedra. All Cu–Cu bond lengths are 2.69 Å. There are two shorter (2.49 Å) and two longer (2.50 Å) Cu–Ge bond lengths. There are four inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to four Hf and four equivalent Ge atoms. All Ge–Ge bond lengths are 2.69 Å. In the second Ge site, Ge is bonded in a 8-coordinate geometry to four equivalent Hf and four equivalent Cu atoms. In the third Ge site, Ge is bonded in a 4-coordinate geometry to six equivalent Hf and two equivalent Ge atoms. Both Ge–Ge bond lengths are 2.65 Å. In the fourth Ge site, Ge is bonded in a 8-coordinate geometry to four Hf and four equivalent Ge atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfGa by Materials Project

HfGa crystallizes in the orthorhombic Pbcm space group. The structure is three-dimensional. there are three inequivalent Hf sites. In the first Hf site, Hf is bonded in a 6-coordinate geometry to six Ga atoms. There are a spread of Hf–Ga bond distances ranging from 2.80–2.93 Å. In the second Hf site, Hf is bonded in a 9-coordinate geometry to nine Ga atoms. There are a spread of Hf–Ga bond distances ranging from 2.80–2.99 Å. In the third Hf site, Hf is bonded to seven Ga atoms to form a mixture of distorted face, edge, and corner-sharing HfGa7 pentagonal bipyramids. There are a spread of Hf–Ga bond distances ranging from 2.71–3.10 Å. There are three inequivalent Ga sites. In the first Ga site, Ga is bonded in a 10-coordinate geometry to six Hf and four Ga atoms. There are two shorter (2.65 Å) and two longer (2.84 Å) Ga–Ga bond lengths. In the second Ga site, Ga is bonded in a 9-coordinate geometry to nine Hf atoms. In the third Ga site, Ga is bonded in a 9-coordinate geometry to seven Hf and two equivalent Ga atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf5Re24 by Materials Project

Hf5Re24 crystallizes in the cubic I-43m space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 12-coordinate geometry to four equivalent Hf and twelve equivalent Re atoms. All Hf–Hf bond lengths are 3.14 Å. All Hf–Re bond lengths are 3.06 Å. In the second Hf site, Hf is bonded in a 3-coordinate geometry to one Hf and fifteen Re atoms. There are a spread of Hf–Re bond distances ranging from 2.79–3.24 Å. There are two inequivalent Re sites. In the first Re site, Re is bonded in a 1-coordinate geometry to two equivalent Hf and eleven Re atoms. There are a spread of Re–Re bond distances ranging from 2.56–2.93 Å. In the second Re site, Re is bonded to four Hf and eight Re atoms to form a mixture of distorted edge, corner, and face-sharing ReHf4Re8 cuboctahedra. There are one shorter (2.52 Å) and two longer (2.68 Å) Re–Re bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf3Cu8 by Materials Project

Cu8Hf3 is Bergman Structure: Mg32(Al,Zn)49 Bergman-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 12-coordinate geometry to twelve Cu atoms. There are a spread of Hf–Cu bond distances ranging from 2.68–3.03 Å. In the second Hf site, Hf is bonded in a 1-coordinate geometry to thirteen Cu atoms. There are a spread of Hf–Cu bond distances ranging from 2.65–3.12 Å. There are six inequivalent Cu sites. In the first Cu site, Cu is bonded in a 12-coordinate geometry to five Hf and seven Cu atoms. There are a spread of Cu–Cu bond distances ranging from 2.42–2.81 Å. In the second Cu site, Cu is bonded to three Hf and nine Cu atoms to form distorted CuHf3Cu9 cuboctahedra that share corners with five equivalent CuHf5Cu7 cuboctahedra and faces with four CuHf3Cu9 cuboctahedra. There are a spread of Cu–Cu bond distances ranging from 2.51–2.63 Å. In the third Cu site, Cu is bonded to five Hf and seven Cu atoms to form CuHf5Cu7 cuboctahedra that share corners with five equivalent CuHf3Cu9 cuboctahedra, edges with two equivalent CuHf5Cu7 cuboctahedra, and faces with two equivalent CuHf3Cu9 cuboctahedra. There are a spread of Cu–Cu bond distances ranging from 2.46–2.56 Å. In the fourth Cu site, Cu is bonded in a 4-coordinate geometry to four Hf and nine Cu atoms. There are a spread of Cu–Cu bond distances ranging from 2.67–2.97 Å. In the fifth Cu site, Cu is bonded in a 12-coordinate geometry to five Hf and seven Cu atoms. The Cu–Cu bond length is 2.51 Å. In the sixth Cu site, Cu is bonded in a 5-coordinate geometry to six Hf and five Cu atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf5Ge4 by Materials Project

Hf5Ge4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Hf sites. In the first Hf site, Hf is bonded to seven Ge atoms to form distorted HfGe7 pentagonal bipyramids that share corners with four equivalent HfGe6 octahedra, corners with six equivalent HfGe7 pentagonal bipyramids, edges with two equivalent HfGe7 pentagonal bipyramids, faces with two equivalent HfGe6 octahedra, and faces with three equivalent HfGe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 46–52°. There are a spread of Hf–Ge bond distances ranging from 2.79–3.15 Å. In the second Hf site, Hf is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Hf–Ge bond distances ranging from 2.66–2.82 Å. In the third Hf site, Hf is bonded to six Ge atoms to form distorted HfGe6 octahedra that share corners with four equivalent HfGe6 octahedra, corners with eight equivalent HfGe7 pentagonal bipyramids, and faces with four equivalent HfGe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 46–55°. There are a spread of Hf–Ge bond distances ranging from 2.69–2.93 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to eight Hf and one Ge atom. The Ge–Ge bond length is 2.65 Å. In the second Ge site, Ge is bonded in a 8-coordinate geometry to eight Hf atoms. In the third Ge site, Ge is bonded in a 9-coordinate geometry to eight Hf and one Ge atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf5Al3N by Materials Project

Hf5Al3N crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 6-coordinate geometry to two equivalent Hf and six equivalent Al atoms. Both Hf–Hf bond lengths are 2.83 Å. All Hf–Al bond lengths are 2.84 Å. In the second Hf site, Hf is bonded in a 2-coordinate geometry to five equivalent Al and two equivalent N atoms. There are a spread of Hf–Al bond distances ranging from 2.83–3.18 Å. Both Hf–N bond lengths are 2.30 Å. Al is bonded in a 9-coordinate geometry to nine Hf atoms. N is bonded to six equivalent Hf atoms to form face-sharing NHf6 octahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf2Ga3Cu by Materials Project

Hf2CuGa3 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 12-coordinate geometry to three equivalent Cu and nine Ga atoms. There are two shorter (3.02 Å) and one longer (3.08 Å) Hf–Cu bond lengths. There are a spread of Hf–Ga bond distances ranging from 2.85–3.20 Å. In the second Hf site, Hf is bonded in a 10-coordinate geometry to three equivalent Cu and nine Ga atoms. There are two shorter (2.90 Å) and one longer (2.95 Å) Hf–Cu bond lengths. There are a spread of Hf–Ga bond distances ranging from 2.87–3.28 Å. Cu is bonded in a 10-coordinate geometry to six Hf and four Ga atoms. There are a spread of Cu–Ga bond distances ranging from 2.40–2.61 Å. There are three inequivalent Ga sites. In the first Ga site, Ga is bonded in a 10-coordinate geometry to six Hf, one Cu, and three Ga atoms. There are two shorter (2.52 Å) and one longer (2.78 Å) Ga–Ga bond lengths. In the second Ga site, Ga is bonded in a 10-coordinate geometry to six Hf, two equivalent Cu, and two Ga atoms. The Ga–Ga bond length is 2.56 Å. In the third Ga site, Ga is bonded in a 10-coordinate geometry to six Hf, one Cu, and three Ga atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsHfMg6 by Materials Project

CsMg6Hf crystallizes in the monoclinic Pm space group. The structure is three-dimensional. Cs is bonded to twelve Mg atoms to form CsMg12 cuboctahedra that share corners with four equivalent CsMg12 cuboctahedra, corners with eight equivalent HfMg12 cuboctahedra, edges with eight MgCs2Hf2Mg8 cuboctahedra, faces with two equivalent CsMg12 cuboctahedra, faces with four MgCs2Hf2Mg8 cuboctahedra, and faces with four equivalent HfMg12 cuboctahedra. There are a spread of Cs–Mg bond distances ranging from 3.48–3.69 Å. There are six inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent Cs, eight Mg, and two equivalent Hf atoms to form distorted MgCs2Hf2Mg8 cuboctahedra that share corners with twelve MgCs2Hf2Mg8 cuboctahedra, edges with four equivalent CsMg12 cuboctahedra, edges with four equivalent HfMg12 cuboctahedra, faces with two equivalent CsMg12 cuboctahedra, faces with two equivalent HfMg12 cuboctahedra, and faces with six MgCs2Hf2Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.36–3.42 Å. There are one shorter (3.45 Å) and one longer (3.51 Å) Mg–Hf bond lengths. In the second Mg site, Mg is bonded to two equivalent Cs, eight Mg, and two equivalent Hf atoms to form distorted MgCs2Hf2Mg8 cuboctahedra that share corners with twelve MgCs2Hf2Mg8 cuboctahedra, edges with four equivalent CsMg12 cuboctahedra, edges with four equivalent HfMg12 cuboctahedra, faces with two equivalent CsMg12 cuboctahedra, faces with two equivalent HfMg12 cuboctahedra, and faces with six MgCs2Hf2Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.37–3.42 Å. There are one shorter (3.45 Å) and one longer (3.51 Å) Mg–Hf bond lengths. In the third Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Cs, six Mg, and two equivalent Hf atoms. There are one shorter (2.93 Å) and one longer (2.97 Å) Mg–Mg bond lengths. Both Mg–Hf bond lengths are 3.12 Å. In the fourth Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Cs, six Mg, and two equivalent Hf atoms. There are one shorter (2.94 Å) and one longer (2.96 Å) Mg–Mg bond lengths. Both Mg–Hf bond lengths are 3.11 Å. In the fifth Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Cs, six Mg, and two equivalent Hf atoms. Both Mg–Hf bond lengths are 3.11 Å. In the sixth Mg site, Mg is bonded in a 10-coordinate geometry to two equivalent Cs, six Mg, and two equivalent Hf atoms. Both Mg–Hf bond lengths are 3.12 Å. Hf is bonded to twelve Mg atoms to form HfMg12 cuboctahedra that share corners with four equivalent HfMg12 cuboctahedra, corners with eight equivalent CsMg12 cuboctahedra, edges with eight MgCs2Hf2Mg8 cuboctahedra, faces with two equivalent HfMg12 cuboctahedra, faces with four equivalent CsMg12 cuboctahedra, and faces with four MgCs2Hf2Mg8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf3Mg by Materials Project

MgHf3 is Copper-derived structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Mg is bonded to twelve Hf atoms to form MgHf12 cuboctahedra that share corners with four equivalent MgHf12 cuboctahedra, corners with eight equivalent HfHf8Mg4 cuboctahedra, edges with eight equivalent MgHf12 cuboctahedra, edges with sixteen equivalent HfHf8Mg4 cuboctahedra, faces with four equivalent MgHf12 cuboctahedra, and faces with fourteen HfHf8Mg4 cuboctahedra. There are four shorter (3.12 Å) and eight longer (3.15 Å) Mg–Hf bond lengths. There are two inequivalent Hf sites. In the first Hf site, Hf is bonded to four equivalent Mg and eight equivalent Hf atoms to form HfHf8Mg4 cuboctahedra that share corners with four equivalent HfHf8Mg4 cuboctahedra, corners with eight equivalent MgHf12 cuboctahedra, edges with twenty-four HfHf8Mg4 cuboctahedra, faces with six equivalent MgHf12 cuboctahedra, and faces with twelve HfHf8Mg4 cuboctahedra. All Hf–Hf bond lengths are 3.15 Å. In the second Hf site, Hf is bonded to four equivalent Mg and eight Hf atoms to form HfHf8Mg4 cuboctahedra that share corners with twelve equivalent HfHf8Mg4 cuboctahedra, edges with eight equivalent MgHf12 cuboctahedra, edges with sixteen HfHf8Mg4 cuboctahedra, faces with four equivalent MgHf12 cuboctahedra, and faces with fourteen HfHf8Mg4 cuboctahedra. All Hf–Hf bond lengths are 3.12 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf5GaSn3 by Materials Project

Hf5GaSn3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded to two equivalent Ga and five equivalent Sn atoms to form a mixture of distorted edge, corner, and face-sharing HfGa2Sn5 pentagonal bipyramids. Both Hf–Ga bond lengths are 2.74 Å. There are three shorter (2.98 Å) and two longer (3.10 Å) Hf–Sn bond lengths. In the second Hf site, Hf is bonded in a 6-coordinate geometry to two equivalent Hf and six equivalent Sn atoms. Both Hf–Hf bond lengths are 2.91 Å. All Hf–Sn bond lengths are 3.05 Å. Ga is bonded to six equivalent Hf atoms to form distorted face-sharing GaHf6 octahedra. Sn is bonded in a 9-coordinate geometry to nine Hf atoms.

36 MATERIALS SCIENCE↗