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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Hf(FeSi)2 by Materials Project

Hf(FeSi)2 crystallizes in the orthorhombic Pbcm space group. The structure is three-dimensional. Hf4+ is bonded in a 6-coordinate geometry to eight Si4- atoms. There are a spread of Hf–Si bond distances ranging from 2.70–3.07 Å. There are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are a spread of Fe–Si bond distances ranging from 2.28–2.40 Å. In the second Fe2+ site, Fe2+ is bonded in a 7-coordinate geometry to two equivalent Fe2+ and five Si4- atoms. Both Fe–Fe bond lengths are 2.51 Å. There are a spread of Fe–Si bond distances ranging from 2.38–2.48 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to four equivalent Hf4+ and five Fe2+ atoms. In the second Si4- site, Si4- is bonded in a 11-coordinate geometry to four equivalent Hf4+, five Fe2+, and two equivalent Si4- atoms. Both Si–Si bond lengths are 2.51 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfFeSi2 by Materials Project

HfFeSi2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent Hf sites. In the first Hf site, Hf is bonded in a 1-coordinate geometry to three Fe and eight Si atoms. There are one shorter (2.28 Å) and two longer (2.91 Å) Hf–Fe bond lengths. There are a spread of Hf–Si bond distances ranging from 2.72–3.27 Å. In the second Hf site, Hf is bonded in a 7-coordinate geometry to four Fe and seven Si atoms. All Hf–Fe bond lengths are 3.06 Å. There are a spread of Hf–Si bond distances ranging from 2.66–3.13 Å. In the third Hf site, Hf is bonded in a 1-coordinate geometry to three Fe and eight Si atoms. There are one shorter (2.28 Å) and two longer (2.91 Å) Hf–Fe bond lengths. There are a spread of Hf–Si bond distances ranging from 2.72–3.28 Å. There are five inequivalent Fe sites. In the first Fe site, Fe is bonded to four Hf, two equivalent Fe, and six Si atoms to form distorted FeHf4Fe2Si6 cuboctahedra that share corners with four FeHf4Fe2Si6 cuboctahedra, corners with two equivalent FeHf2Si4 octahedra, edges with two equivalent FeHf4Fe2Si6 cuboctahedra, and faces with four FeHf4Fe2Si6 cuboctahedra. The corner-sharing octahedral tilt angles are 26°. Both Fe–Fe bond lengths are 2.55 Å. There are a spread of Fe–Si bond distances ranging from 2.37–2.41 Å. In the second Fe site, Fe is bonded to two Hf and four Si atoms to form distorted FeHf2Si4 octahedra that share corners with four FeHf4Fe2Si6 cuboctahedra and edges with two equivalent FeHf2Si4 octahedra. There are two shorter (2.29 Å) and two longer (2.34 Å) Fe–Si bond lengths. In the third Fe site, Fe is bonded to four Hf, two equivalent Fe, and six Si atoms to form distorted FeHf4Fe2Si6 cuboctahedra that share corners with four FeHf4Fe2Si6 cuboctahedra, corners with two equivalent FeHf2Si4 octahedra, edges with two equivalent FeHf4Fe2Si6 cuboctahedra, and faces with four FeHf4Fe2Si6 cuboctahedra. The corner-sharing octahedral tilt angles are 26°. Both Fe–Fe bond lengths are 2.55 Å. There are a spread of Fe–Si bond distances ranging from 2.37–2.41 Å. In the fourth Fe site, Fe is bonded to four Hf, two equivalent Fe, and six Si atoms to form distorted FeHf4Fe2Si6 cuboctahedra that share corners with four FeHf4Fe2Si6 cuboctahedra, corners with two equivalent FeHf2Si4 octahedra, edges with two equivalent FeHf4Fe2Si6 cuboctahedra, and faces with four FeHf4Fe2Si6 cuboctahedra. The corner-sharing octahedral tilt angles are 26°. There are a spread of Fe–Si bond distances ranging from 2.37–2.41 Å. In the fifth Fe site, Fe is bonded to four Hf, two equivalent Fe, and six Si atoms to form distorted FeHf4Fe2Si6 cuboctahedra that share corners with four FeHf4Fe2Si6 cuboctahedra, corners with two equivalent FeHf2Si4 octahedra, edges with two equivalent FeHf4Fe2Si6 cuboctahedra, and faces with four FeHf4Fe2Si6 cuboctahedra. The corner-sharing octahedral tilt angles are 26°. There are a spread of Fe–Si bond distances ranging from 2.37–2.41 Å. There are six inequivalent Si sites. In the first Si site, Si is bonded in a 3-coordinate geometry to four Hf, two equivalent Fe, and two equivalent Si atoms. There are one shorter (2.52 Å) and one longer (2.58 Å) Si–Si bond lengths. In the second Si site, Si is bonded in a 7-coordinate geometry to three Hf and four Fe atoms. In the third Si site, Si is bonded in a 12-coordinate geometry to four Hf and four Fe atoms. In the fourth Si site, Si is bonded in a 10-coordinate geometry to six Hf, two equivalent Fe, and two equivalent Si atoms. There are one shorter (2.46 Å) and one longer (2.64 Å) Si–Si bond lengths. In the fifth Si site, Si is bonded in a 6-coordinate geometry to three Hf, two Fe, and one Si atom. The Si–Si bond length is 2.33 Å. In the sixth Si site, Si is bonded in a 6-coordinate geometry to three Hf, two Fe, and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf6Fe16Si7 by Materials Project

Hf6Fe16Si7 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Hf is bonded in a 12-coordinate geometry to eight Fe and four equivalent Si atoms. There are four shorter (2.78 Å) and four longer (2.85 Å) Hf–Fe bond lengths. All Hf–Si bond lengths are 2.90 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded in a 7-coordinate geometry to three equivalent Hf, six Fe, and four Si atoms. There are three shorter (2.48 Å) and three longer (2.76 Å) Fe–Fe bond lengths. There are one shorter (2.39 Å) and three longer (2.50 Å) Fe–Si bond lengths. In the second Fe site, Fe is bonded in a 12-coordinate geometry to three equivalent Hf, six Fe, and three equivalent Si atoms. All Fe–Fe bond lengths are 2.41 Å. All Fe–Si bond lengths are 2.34 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded in a body-centered cubic geometry to eight equivalent Fe atoms. In the second Si site, Si is bonded to four equivalent Hf and eight Fe atoms to form a mixture of corner and face-sharing SiHf4Fe8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf2Fe3Si by Materials Project

Hf2Fe3Si is Hexagonal Laves-derived structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Hf is bonded in a 12-coordinate geometry to nine equivalent Fe and three equivalent Si atoms. There are three shorter (2.87 Å) and six longer (2.89 Å) Hf–Fe bond lengths. All Hf–Si bond lengths are 2.90 Å. Fe is bonded to six equivalent Hf, four equivalent Fe, and two equivalent Si atoms to form FeHf6Fe4Si2 cuboctahedra that share corners with four equivalent SiHf6Fe6 cuboctahedra, corners with fourteen equivalent FeHf6Fe4Si2 cuboctahedra, edges with six equivalent FeHf6Fe4Si2 cuboctahedra, faces with six equivalent SiHf6Fe6 cuboctahedra, and faces with twelve equivalent FeHf6Fe4Si2 cuboctahedra. There are two shorter (2.43 Å) and two longer (2.52 Å) Fe–Fe bond lengths. Both Fe–Si bond lengths are 2.47 Å. Si is bonded to six equivalent Hf and six equivalent Fe atoms to form SiHf6Fe6 cuboctahedra that share corners with twelve equivalent FeHf6Fe4Si2 cuboctahedra, edges with six equivalent SiHf6Fe6 cuboctahedra, faces with two equivalent SiHf6Fe6 cuboctahedra, and faces with eighteen equivalent FeHf6Fe4Si2 cuboctahedra.

36 MATERIALS SCIENCE↗