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DOE OSTI · 1203449

Materials Data on NaTa3N5 by Materials Project

Abstract

NaTa3N5 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Na1+ is bonded in a 7-coordinate geometry to seven N3- atoms. There are a spread of Na–N bond distances ranging from 2.48–2.57 Å. There are two inequivalent Ta+4.67+ sites. In the first Ta+4.67+ site, Ta+4.67+ is bonded to six N3- atoms to form a mixture of distorted edge and corner-sharing TaN6 octahedra. The corner-sharing octahedra tilt angles range from 17–58°. There are a spread of Ta–N bond distances ranging from 2.00–2.42 Å. In the second Ta+4.67+ site, Ta+4.67+ is bonded to six N3- atoms to form a mixture of distorted edge and corner-sharing TaN6 octahedra. The corner-sharing octahedra tilt angles range from 17–25°. There are a spread of Ta–N bond distances ranging from 2.07–2.15 Å. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded to one Na1+ and four Ta+4.67+ atoms to form a mixture of distorted edge and corner-sharing NNaTa4 trigonal bipyramids. In the second N3- site, N3- is bonded to two equivalent Na1+ and three Ta+4.67+ atoms to form distorted NNa2Ta3 trigonal bipyramids that share corners with twelve NNaTa4 trigonal bipyramids, edges with six NNaTa4 trigonal bipyramids, and a faceface with one NNa2Ta3 trigonal bipyramid. In the third N3- site, N3- is bonded to one Na1+ and four Ta+4.67+ atoms to form a mixture of distorted edge and corner-sharing NNaTa4 trigonal bipyramids.

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2020-07-17. Materials Data on NaTa3N5 by Materials Project. https://doi.org/10.17188/1203449

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36 MATERIALS SCIENCE↗