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DOE OSTI · 1195012

Materials Data on NiAs2 by Materials Project

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Abstract

NiAs2 is Marcasite structured and crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. Ni2+ is bonded to six equivalent As1- atoms to form NiAs6 octahedra that share corners with eight equivalent NiAs6 octahedra, corners with six equivalent AsNi3As tetrahedra, and edges with two equivalent NiAs6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are two shorter (2.36 Å) and four longer (2.40 Å) Ni–As bond lengths. 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 equivalent AsNi3As tetrahedra, and an edgeedge with one AsNi3As tetrahedra. The corner-sharing octahedra tilt angles range from 75–77°. The As–As bond length is 2.49 Å.

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36 MATERIALS SCIENCEAs-Nicrystal structureNiAs2

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2020-07-15. Materials Data on NiAs2 by Materials Project. https://doi.org/10.17188/1195012

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