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DOE OSTI · 1284083

Materials Data on Nb16N9 by Materials Project

Abstract

Nb16N9 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are eight inequivalent Nb sites. In the first Nb site, Nb is bonded in a linear geometry to two N atoms. Both Nb–N bond lengths are 2.22 Å. In the second Nb site, Nb is bonded to five N atoms to form corner-sharing NbN5 square pyramids. There are a spread of Nb–N bond distances ranging from 2.16–2.18 Å. In the third Nb site, Nb is bonded in a linear geometry to two N atoms. Both Nb–N bond lengths are 2.21 Å. In the fourth Nb site, Nb is bonded in a square co-planar geometry to four N atoms. There are two shorter (2.16 Å) and two longer (2.19 Å) Nb–N bond lengths. In the fifth Nb site, Nb is bonded in a T-shaped geometry to three N atoms. There are one shorter (2.21 Å) and two longer (2.23 Å) Nb–N bond lengths. In the sixth Nb site, Nb is bonded in a rectangular see-saw-like geometry to four N atoms. There are a spread of Nb–N bond distances ranging from 2.16–2.19 Å. In the seventh Nb site, Nb is bonded in a square co-planar geometry to four N atoms. All Nb–N bond lengths are 2.18 Å. In the eighth Nb site, Nb is bonded in a T-shaped geometry to three N atoms. There are one shorter (2.21 Å) and two longer (2.23 Å) Nb–N bond lengths. There are five inequivalent N sites. In the first N site, N is bonded to six Nb atoms to form a mixture of edge and corner-sharing NNb6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. In the second N site, N is bonded to six Nb atoms to form a mixture of edge and corner-sharing NNb6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. In the third N site, N is bonded to six Nb atoms to form a mixture of edge and corner-sharing NNb6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. In the fourth N site, N is bonded to six Nb atoms to form a mixture of edge and corner-sharing NNb6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. In the fifth N site, N is bonded to six Nb atoms to form edge-sharing NNb6 octahedra.

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2020-05-03. Materials Data on Nb16N9 by Materials Project. https://doi.org/10.17188/1284083

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36 MATERIALS SCIENCE↗