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4 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Hf3(NiGe)4 by Materials Project

Hf3Ni4Ge4 crystallizes in the orthorhombic Immm 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 six equivalent Ni and six Ge atoms. All Hf–Ni bond lengths are 2.84 Å. There are two shorter (2.84 Å) and four longer (2.87 Å) Hf–Ge bond lengths. In the second Hf site, Hf is bonded to eight equivalent Ni and six Ge atoms to form face-sharing HfNi8Ge6 octahedra. All Hf–Ni bond lengths are 3.28 Å. There are two shorter (2.75 Å) and four longer (2.77 Å) Hf–Ge bond lengths. Ni is bonded in a 12-coordinate geometry to five Hf, three equivalent Ni, and four Ge atoms. There are one shorter (2.61 Å) and two longer (2.79 Å) Ni–Ni bond lengths. There are a spread of Ni–Ge bond distances ranging from 2.38–2.41 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to three Hf and six equivalent Ni atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six Hf, two equivalent Ni, and one Ge atom. The Ge–Ge bond length is 2.61 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf6Ni16Ge7 by Materials Project

Hf6Ni16Ge7 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Hf is bonded in a 12-coordinate geometry to eight Ni and four equivalent Ge atoms. There are four shorter (2.78 Å) and four longer (2.82 Å) Hf–Ni bond lengths. All Hf–Ge bond lengths are 2.95 Å. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded in a 7-coordinate geometry to three equivalent Hf, six Ni, and four Ge atoms. There are three shorter (2.61 Å) and three longer (2.75 Å) Ni–Ni bond lengths. There are one shorter (2.38 Å) and three longer (2.56 Å) Ni–Ge bond lengths. In the second Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Hf, three equivalent Ni, and three equivalent Ge atoms. All Ni–Ge bond lengths are 2.37 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a body-centered cubic geometry to eight equivalent Ni atoms. In the second Ge site, Ge is bonded to four equivalent Hf and eight Ni atoms to form a mixture of corner and face-sharing GeHf4Ni8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfNiGe by Materials Project

HfNiGe is half-Heusler structured and crystallizes in the cubic F-43m space group. The structure is three-dimensional. Hf is bonded in a body-centered cubic geometry to four equivalent Ni and four equivalent Ge atoms. All Hf–Ni bond lengths are 2.65 Å. All Hf–Ge bond lengths are 2.65 Å. Ni is bonded to four equivalent Hf atoms to form NiHf4 tetrahedra that share corners with four equivalent GeHf4 tetrahedra, corners with twelve equivalent NiHf4 tetrahedra, and edges with six equivalent GeHf4 tetrahedra. Ge is bonded to four equivalent Hf atoms to form GeHf4 tetrahedra that share corners with four equivalent NiHf4 tetrahedra, corners with twelve equivalent GeHf4 tetrahedra, and edges with six equivalent NiHf4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfNiGe by Materials Project

HfNiGe crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Hf is bonded in a 11-coordinate geometry to six equivalent Ni and five equivalent Ge atoms. There are a spread of Hf–Ni bond distances ranging from 2.85–3.08 Å. There are a spread of Hf–Ge bond distances ranging from 2.73–2.78 Å. Ni is bonded in a 12-coordinate geometry to six equivalent Hf, two equivalent Ni, and four equivalent Ge atoms. Both Ni–Ni bond lengths are 2.84 Å. There are a spread of Ni–Ge bond distances ranging from 2.40–2.48 Å. Ge is bonded in a 9-coordinate geometry to five equivalent Hf and four equivalent Ni atoms.

36 MATERIALS SCIENCE↗