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7 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on HfGe2 by Materials Project

HfGe2 is Zirconium Disilicide structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Hf is bonded in a 10-coordinate geometry to ten Ge atoms. There are a spread of Hf–Ge bond distances ranging from 2.78–3.13 Å. There are two inequivalent Ge sites. In the first 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 2.63 Å. In the second Ge site, Ge is bonded in a 8-coordinate geometry to four equivalent Hf and four equivalent Ge atoms. All Ge–Ge bond lengths are 2.70 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf5Ge3 by Materials Project

Hf5Ge3 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 six equivalent Ge atoms. All Hf–Ge bond lengths are 2.84 Å. In the second Hf site, Hf is bonded in a 5-coordinate geometry to five equivalent Ge atoms. There are a spread of Hf–Ge bond distances ranging from 2.74–2.99 Å. Ge is bonded in a 9-coordinate geometry to nine Hf 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 Hf3Ge2 by Materials Project

Hf3Ge2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a square co-planar geometry to four equivalent Ge atoms. All Hf–Ge bond lengths are 2.81 Å. In the second Hf site, Hf is bonded in a 6-coordinate geometry to six equivalent Ge atoms. There are two shorter (2.74 Å) and four longer (2.86 Å) Hf–Ge bond lengths. Ge is bonded in a 9-coordinate geometry to eight Hf and one Ge atom. The Ge–Ge bond length is 2.65 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf3Ge by Materials Project

Hf3Ge is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded to eight Hf and four equivalent Ge atoms to form distorted HfHf8Ge4 cuboctahedra that share corners with twelve equivalent HfHf8Ge4 cuboctahedra, edges with eight equivalent HfHf8Ge4 cuboctahedra, edges with eight equivalent GeHf12 cuboctahedra, faces with four equivalent GeHf12 cuboctahedra, and faces with ten equivalent HfHf8Ge4 cuboctahedra. There are four shorter (2.96 Å) and four longer (3.12 Å) Hf–Hf bond lengths. All Hf–Ge bond lengths are 3.12 Å. In the second Hf site, Hf is bonded in a square co-planar geometry to eight equivalent Hf and four equivalent Ge atoms. All Hf–Ge bond lengths are 2.96 Å. Ge is bonded to twelve Hf atoms to form GeHf12 cuboctahedra that share corners with four equivalent GeHf12 cuboctahedra, edges with eight equivalent GeHf12 cuboctahedra, edges with sixteen equivalent HfHf8Ge4 cuboctahedra, faces with four equivalent GeHf12 cuboctahedra, and faces with eight equivalent HfHf8Ge4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf3Ge by Materials Project

Hf3Ge crystallizes in the tetragonal P4_2/n space group. The structure is three-dimensional. there are three inequivalent Hf sites. In the first Hf site, Hf is bonded in a 3-coordinate geometry to three equivalent Ge atoms. There are a spread of Hf–Ge bond distances ranging from 2.76–2.94 Å. In the second Hf site, Hf is bonded in a distorted see-saw-like geometry to four equivalent Ge atoms. There are a spread of Hf–Ge bond distances ranging from 2.77–2.83 Å. In the third Hf site, Hf is bonded in a distorted bent 150 degrees geometry to two equivalent Ge atoms. There are one shorter (2.78 Å) and one longer (2.84 Å) Hf–Ge bond lengths. Ge is bonded in a 9-coordinate geometry to nine Hf atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf2Ge by Materials Project

Hf2Ge crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. Hf is bonded in a 2-coordinate geometry to two equivalent Ge atoms. Both Hf–Ge bond lengths are 2.68 Å. Ge is bonded to four equivalent Hf and two equivalent Ge atoms to form distorted corner-sharing GeHf4Ge2 octahedra. The corner-sharing octahedra tilt angles range from 0–44°. Both Ge–Ge bond lengths are 2.57 Å.

36 MATERIALS SCIENCE↗