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DOE OSTI · 1190878

Materials Data on Li7TaN4 by Materials Project

Abstract

Li7TaN4 crystallizes in the cubic Pa-3 space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four N3- atoms to form distorted LiN4 tetrahedra that share corners with two equivalent TaN4 tetrahedra, corners with fourteen LiN4 tetrahedra, an edgeedge with one TaN4 tetrahedra, and edges with five LiN4 tetrahedra. There are a spread of Li–N bond distances ranging from 2.11–2.26 Å. In the second Li1+ site, Li1+ is bonded to four N3- atoms to form LiN4 tetrahedra that share corners with four equivalent TaN4 tetrahedra, corners with twelve LiN4 tetrahedra, and edges with six LiN4 tetrahedra. There are one shorter (2.15 Å) and three longer (2.19 Å) Li–N bond lengths. In the third Li1+ site, Li1+ is bonded to four N3- atoms to form distorted LiN4 tetrahedra that share corners with two equivalent TaN4 tetrahedra, corners with fourteen LiN4 tetrahedra, an edgeedge with one TaN4 tetrahedra, and edges with five LiN4 tetrahedra. There are a spread of Li–N bond distances ranging from 2.10–2.25 Å. Ta5+ is bonded to four N3- atoms to form TaN4 tetrahedra that share corners with sixteen LiN4 tetrahedra and edges with six LiN4 tetrahedra. There is one shorter (1.96 Å) and three longer (1.98 Å) Ta–N bond length. There are twelve inequivalent N3- sites. In the first N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. The N–Ta bond length is 1.98 Å. In the second N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.15–2.26 Å. The N–Ta bond length is 1.98 Å. In the third N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. The N–Li bond length is 2.19 Å. The N–Ta bond length is 1.98 Å. In the fourth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. The N–Ta bond length is 1.98 Å. In the fifth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.15–2.26 Å. The N–Ta bond length is 1.98 Å. In the sixth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.21 Å. The N–Ta bond length is 1.98 Å. In the seventh N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. In the eighth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.21 Å. In the ninth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. In the tenth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. The N–Ta bond length is 1.98 Å. In the eleventh N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. The N–Li bond length is 2.15 Å. In the twelfth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are three shorter (2.11 Å) and three longer (2.25 Å) N–Li bond lengths. The N–Ta bond length is 1.96 Å.

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2020-05-02. Materials Data on Li7TaN4 by Materials Project. https://doi.org/10.17188/1190878

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