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DOE OSTI · 1262561

Materials Data on NiAs2 by Materials Project

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Abstract

NiAs2 is Pyrite-like structured and crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. Ni2+ is bonded to six As1- atoms to form NiAs6 octahedra that share corners with ten equivalent NiAs6 octahedra, corners with six AsNi3As tetrahedra, and an edgeedge with one NiAs6 octahedra. The corner-sharing octahedra tilt angles range from 55–65°. There are a spread of Ni–As bond distances ranging from 2.37–2.41 Å. There are two inequivalent As1- sites. In the first As1- site, As1- is bonded to three equivalent Ni2+ and one As1- atom to form distorted AsNi3As tetrahedra that share corners with three equivalent NiAs6 octahedra and corners with fifteen AsNi3As tetrahedra. The corner-sharing octahedra tilt angles range from 71–79°. The As–As bond length is 2.49 Å. In the second As1- site, As1- is bonded to three equivalent Ni2+ and one As1- atom to form distorted AsNi3As tetrahedra that share corners with three equivalent NiAs6 octahedra, corners with thirteen AsNi3As tetrahedra, and an edgeedge with one AsNi3As tetrahedra. The corner-sharing octahedra tilt angles range from 75–84°.

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36 MATERIALS SCIENCEAs-Nicrystal structureNiAs2

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2020-07-14. Materials Data on NiAs2 by Materials Project. https://doi.org/10.17188/1262561

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