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DOE OSTI · 1723164

Materials Data on Mg6FeNi by Materials Project

Abstract

Mg6FeNi crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded to eight Mg, two equivalent Fe, and two equivalent Ni atoms to form distorted MgMg8Fe2Ni2 cuboctahedra that share corners with four equivalent FeMg10Ni2 cuboctahedra, corners with fourteen MgMg8Fe2Ni2 cuboctahedra, edges with two equivalent FeMg10Ni2 cuboctahedra, edges with four MgMg8Fe2Ni2 cuboctahedra, faces with two equivalent FeMg10Ni2 cuboctahedra, and faces with six MgMg8Fe2Ni2 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 2.81–3.10 Å. There are one shorter (2.79 Å) and one longer (3.34 Å) Mg–Fe bond lengths. Both Mg–Ni bond lengths are 2.95 Å. In the second Mg site, Mg is bonded to ten Mg and two equivalent Fe atoms to form distorted MgMg10Fe2 cuboctahedra that share corners with four equivalent FeMg10Ni2 cuboctahedra, corners with fourteen MgMg8Fe2Ni2 cuboctahedra, edges with two equivalent FeMg10Ni2 cuboctahedra, edges with four equivalent MgMg8Fe2Ni2 cuboctahedra, faces with two equivalent FeMg10Ni2 cuboctahedra, and faces with six MgMg8Fe2Ni2 cuboctahedra. There are four shorter (2.94 Å) and two longer (2.95 Å) Mg–Mg bond lengths. Both Mg–Fe bond lengths are 2.96 Å. In the third Mg site, Mg is bonded in a 12-coordinate geometry to six Mg, two equivalent Fe, and one Ni atom. There are one shorter (3.03 Å) and one longer (3.10 Å) Mg–Mg bond lengths. Both Mg–Fe bond lengths are 2.93 Å. The Mg–Ni bond length is 2.74 Å. In the fourth Mg site, Mg is bonded in a 2-coordinate geometry to ten Mg and two equivalent Ni atoms. Both Mg–Ni bond lengths are 2.97 Å. Fe is bonded to ten Mg and two equivalent Ni atoms to form distorted FeMg10Ni2 cuboctahedra that share corners with six equivalent FeMg10Ni2 cuboctahedra, corners with twelve MgMg8Fe2Ni2 cuboctahedra, edges with six MgMg8Fe2Ni2 cuboctahedra, faces with two equivalent FeMg10Ni2 cuboctahedra, and faces with six MgMg8Fe2Ni2 cuboctahedra. Both Fe–Ni bond lengths are 2.70 Å. Ni is bonded in a 10-coordinate geometry to eight Mg and two equivalent Fe atoms.

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2020-05-02. Materials Data on Mg6FeNi by Materials Project. https://doi.org/10.17188/1723164

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