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DOE OSTI · 1754204

Materials Data on Hf4Ni3As8 by Materials Project

Abstract

Hf4Ni3As8 crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded in a 8-coordinate geometry to eight As+2.75- atoms. There are four shorter (2.86 Å) and four longer (2.87 Å) Hf–As bond lengths. In the second Hf4+ site, Hf4+ is bonded in a 8-coordinate geometry to eight As+2.75- atoms. There are four shorter (2.83 Å) and four longer (2.85 Å) Hf–As bond lengths. There are two inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded to four equivalent As+2.75- atoms to form a mixture of edge and corner-sharing NiAs4 tetrahedra. All Ni–As bond lengths are 2.40 Å. In the second Ni2+ site, Ni2+ is bonded to four equivalent As+2.75- atoms to form corner-sharing NiAs4 tetrahedra. All Ni–As bond lengths are 2.31 Å. There are four inequivalent As+2.75- sites. In the first As+2.75- site, As+2.75- is bonded in a 6-coordinate geometry to four equivalent Hf4+ and two equivalent Ni2+ atoms. In the second As+2.75- site, As+2.75- is bonded in a 8-coordinate geometry to four equivalent Hf4+ and four equivalent Ni2+ atoms. In the third As+2.75- site, As+2.75- is bonded in a 8-coordinate geometry to four Hf4+ and four equivalent As+2.75- atoms. All As–As bond lengths are 2.71 Å. In the fourth As+2.75- site, As+2.75- is bonded in a 8-coordinate geometry to four Hf4+ and four equivalent As+2.75- atoms.

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2020-05-02. Materials Data on Hf4Ni3As8 by Materials Project. https://doi.org/10.17188/1754204

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