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DOE OSTI · 1277310

Materials Data on Ba4LiMo2N7 by Materials Project

Abstract

LiBa4Mo2N7 crystallizes in the monoclinic P2/c space group. The structure is three-dimensional. Li1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of Li–N bond distances ranging from 1.99–2.64 Å. There are five inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to seven N3- atoms to form distorted BaN7 hexagonal pyramids that share corners with two equivalent BaN7 hexagonal pyramids, a cornercorner with one MoN4 tetrahedra, an edgeedge with one BaN7 hexagonal pyramid, and edges with four MoN4 tetrahedra. There are a spread of Ba–N bond distances ranging from 2.90–3.19 Å. In the second Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven N3- atoms. There are a spread of Ba–N bond distances ranging from 2.77–3.44 Å. In the third Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven N3- atoms. There are a spread of Ba–N bond distances ranging from 2.75–3.30 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 4-coordinate geometry to four N3- atoms. There are two shorter (2.72 Å) and two longer (2.98 Å) Ba–N bond lengths. In the fifth Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven N3- atoms. There are a spread of Ba–N bond distances ranging from 2.73–3.45 Å. There are two inequivalent Mo6+ sites. In the first Mo6+ site, Mo6+ is bonded to four N3- atoms to form MoN4 tetrahedra that share a cornercorner with one MoN4 tetrahedra and edges with two equivalent BaN7 hexagonal pyramids. There are a spread of Mo–N bond distances ranging from 1.86–1.96 Å. In the second Mo6+ site, Mo6+ is bonded to four N3- atoms to form MoN4 tetrahedra that share a cornercorner with one BaN7 hexagonal pyramid, a cornercorner with one MoN4 tetrahedra, and edges with two equivalent BaN7 hexagonal pyramids. There are a spread of Mo–N bond distances ranging from 1.84–1.97 Å. There are eight inequivalent N3- sites. In the first N3- site, N3- is bonded in a 3-coordinate geometry to two equivalent Li1+, two Ba2+, and one Mo6+ atom. In the second N3- site, N3- is bonded in a 5-coordinate geometry to four Ba2+ and one Mo6+ atom. In the third N3- site, N3- is bonded in a 1-coordinate geometry to one Li1+, three Ba2+, and one Mo6+ atom. In the fourth N3- site, N3- is bonded to five Ba2+ and one Mo6+ atom to form distorted NBa5Mo octahedra that share a cornercorner with one NBa5Mo octahedra, corners with two equivalent NBa3Mo2 trigonal bipyramids, and edges with three NBa5Mo octahedra. The corner-sharing octahedral tilt angles are 14°. In the fifth N3- site, N3- is bonded in a 1-coordinate geometry to five Ba2+ and one Mo6+ atom. In the sixth N3- site, N3- is bonded to four Ba2+ and two equivalent Mo6+ atoms to form distorted NBa4Mo2 octahedra that share corners with two equivalent NBa3Mo2 trigonal bipyramids and edges with four equivalent NBa5Mo octahedra. In the seventh N3- site, N3- is bonded to three Ba2+ and two equivalent Mo6+ atoms to form distorted corner-sharing NBa3Mo2 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 28–61°. In the eighth N3- site, N3- is bonded in a 6-coordinate geometry to one Li1+, four Ba2+, and one Mo6+ atom.

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BibTeXRIS

2020-04-30. Materials Data on Ba4LiMo2N7 by Materials Project. https://doi.org/10.17188/1277310

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36 MATERIALS SCIENCE↗