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DOE OSTI · 1188611

Materials Data on HfNi3 by Materials Project

Abstract

HfNi3 is beta Cu3Ti-like structured and 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 to twelve Ni atoms to form HfNi12 cuboctahedra that share corners with six equivalent NiHf4Ni8 cuboctahedra, corners with nine HfNi12 cuboctahedra, edges with twenty-one NiHf4Ni8 cuboctahedra, faces with seven HfNi12 cuboctahedra, and faces with twelve NiHf4Ni8 cuboctahedra. There are nine shorter (2.64 Å) and three longer (2.68 Å) Hf–Ni bond lengths. In the second Hf site, Hf is bonded to twelve Ni atoms to form HfNi12 cuboctahedra that share corners with six equivalent HfNi12 cuboctahedra, corners with twelve NiHf4Ni8 cuboctahedra, edges with eighteen NiHf4Ni8 cuboctahedra, faces with eight HfNi12 cuboctahedra, and faces with twelve NiHf4Ni8 cuboctahedra. There are a spread of Hf–Ni bond distances ranging from 2.63–2.68 Å. In the third Hf site, Hf is bonded to twelve Ni atoms to form HfNi12 cuboctahedra that share corners with twelve HfNi12 cuboctahedra, edges with twenty-four NiHf4Ni8 cuboctahedra, faces with six equivalent HfNi12 cuboctahedra, and faces with twelve NiHf4Ni8 cuboctahedra. All Hf–Ni bond lengths are 2.64 Å. There are six inequivalent Ni sites. In the first Ni site, Ni is bonded to four Hf and eight Ni atoms to form distorted NiHf4Ni8 cuboctahedra that share corners with four HfNi12 cuboctahedra, corners with fourteen NiHf4Ni8 cuboctahedra, edges with six HfNi12 cuboctahedra, edges with twelve NiHf4Ni8 cuboctahedra, faces with four HfNi12 cuboctahedra, and faces with sixteen NiHf4Ni8 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.57–2.65 Å. In the second Ni site, Ni is bonded to four Hf and eight Ni atoms to form distorted NiHf4Ni8 cuboctahedra that share corners with four HfNi12 cuboctahedra, corners with fourteen NiHf4Ni8 cuboctahedra, edges with six HfNi12 cuboctahedra, edges with twelve NiHf4Ni8 cuboctahedra, faces with four HfNi12 cuboctahedra, and faces with sixteen NiHf4Ni8 cuboctahedra. Both Ni–Hf bond lengths are 2.63 Å. There are a spread of Ni–Ni bond distances ranging from 2.57–2.65 Å. In the third Ni site, Ni is bonded to four Hf and eight Ni atoms to form distorted NiHf4Ni8 cuboctahedra that share corners with twelve NiHf4Ni8 cuboctahedra, edges with eight HfNi12 cuboctahedra, edges with sixteen NiHf4Ni8 cuboctahedra, faces with four HfNi12 cuboctahedra, and faces with fourteen NiHf4Ni8 cuboctahedra. There are two shorter (2.46 Å) and two longer (2.80 Å) Ni–Ni bond lengths. In the fourth Ni site, Ni is bonded to four Hf and eight Ni atoms to form distorted NiHf4Ni8 cuboctahedra that share corners with twelve NiHf4Ni8 cuboctahedra, edges with eight HfNi12 cuboctahedra, edges with sixteen NiHf4Ni8 cuboctahedra, faces with four HfNi12 cuboctahedra, and faces with fourteen NiHf4Ni8 cuboctahedra. There are one shorter (2.46 Å) and one longer (2.80 Å) Ni–Ni bond lengths. In the fifth Ni site, Ni is bonded to four Hf and eight Ni atoms to form distorted NiHf4Ni8 cuboctahedra that share corners with two equivalent HfNi12 cuboctahedra, corners with thirteen NiHf4Ni8 cuboctahedra, edges with seven HfNi12 cuboctahedra, edges with fourteen NiHf4Ni8 cuboctahedra, faces with four HfNi12 cuboctahedra, and faces with fifteen NiHf4Ni8 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.47–2.80 Å. In the sixth Ni site, Ni is bonded to four Hf and eight Ni atoms to form distorted NiHf4Ni8 cuboctahedra that share corners with two equivalent HfNi12 cuboctahedra, corners with thirteen NiHf4Ni8 cuboctahedra, edges with seven HfNi12 cuboctahedra, edges with fourteen NiHf4Ni8 cuboctahedra, faces with four HfNi12 cuboctahedra, and faces with fifteen NiHf4Ni8 cuboctahedra.

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2020-07-22. Materials Data on HfNi3 by Materials Project. https://doi.org/10.17188/1188611

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