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DOE OSTI · 1277353

Materials Data on Li16Nb2N8O by Materials Project

Abstract

Li16Nb2N8O crystallizes in the trigonal R-3 space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four N3- atoms to form LiN4 tetrahedra that share corners with four equivalent NbN4 tetrahedra, corners with twelve LiN4 tetrahedra, and edges with six LiN4 tetrahedra. There are three shorter (2.16 Å) and one longer (2.31 Å) Li–N bond lengths. In the second Li1+ site, Li1+ is bonded to three equivalent N3- and one O2- atom to form LiN3O tetrahedra that share corners with three equivalent NbN4 tetrahedra, corners with thirteen LiN4 tetrahedra, and edges with six LiN4 tetrahedra. All Li–N bond lengths are 2.22 Å. The Li–O bond length is 1.99 Å. In the third Li1+ site, Li1+ is bonded to three N3- and one O2- atom to form distorted LiN3O tetrahedra that share a cornercorner with one NbN4 tetrahedra, corners with fifteen LiN4 tetrahedra, an edgeedge with one NbN4 tetrahedra, and edges with five LiN4 tetrahedra. There are a spread of Li–N bond distances ranging from 2.04–2.22 Å. The Li–O bond length is 2.05 Å. In the fourth Li1+ site, Li1+ is bonded to four equivalent N3- atoms to form distorted LiN4 tetrahedra that share corners with two equivalent NbN4 tetrahedra, corners with fourteen LiN4 tetrahedra, an edgeedge with one NbN4 tetrahedra, and edges with five LiN4 tetrahedra. There are a spread of Li–N bond distances ranging from 2.06–2.34 Å. Nb5+ is bonded to four N3- atoms to form NbN4 tetrahedra that share corners with sixteen LiN4 tetrahedra and edges with six LiN4 tetrahedra. All Nb–N bond lengths are 1.98 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Nb5+ atom. In the second N3- site, N3- is bonded in a distorted body-centered cubic geometry to seven Li1+ and one Nb5+ atom. O2- is bonded in a body-centered cubic geometry to eight Li1+ atoms.

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2020-07-14. Materials Data on Li16Nb2N8O by Materials Project. https://doi.org/10.17188/1277353

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36 MATERIALS SCIENCE↗