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DOE OSTI · 1203071

Materials Data on MnWN2 by Materials Project

Abstract

MnWN2 crystallizes in the hexagonal P6_3mc space group. The structure is three-dimensional. W4+ is bonded to six N3- atoms to form WN6 octahedra that share corners with six equivalent MnN4 tetrahedra, edges with six equivalent WN6 octahedra, and edges with three equivalent MnN4 tetrahedra. There are three shorter (2.10 Å) and three longer (2.34 Å) W–N bond lengths. Mn2+ is bonded to four N3- atoms to form MnN4 tetrahedra that share corners with six equivalent WN6 octahedra, corners with six equivalent MnN4 tetrahedra, and edges with three equivalent WN6 octahedra. The corner-sharing octahedra tilt angles range from 27–57°. There is three shorter (1.81 Å) and one longer (2.01 Å) Mn–N bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted trigonal non-coplanar geometry to three equivalent W4+ and three equivalent Mn2+ atoms. In the second N3- site, N3- is bonded in a distorted rectangular see-saw-like geometry to three equivalent W4+ and one Mn2+ atom.

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2020-07-16. Materials Data on MnWN2 by Materials Project. https://doi.org/10.17188/1203071

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36 MATERIALS SCIENCE↗