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DOE OSTI · 1696265

Materials Data on Ca3ReN4 by Materials Project

Abstract

Ca3ReN4 crystallizes in the trigonal P31c space group. The structure is three-dimensional. there are eleven inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a trigonal planar geometry to three equivalent N3- atoms. All Ca–N bond lengths are 2.37 Å. In the second Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six N3- atoms. There are three shorter (2.51 Å) and three longer (2.90 Å) Ca–N bond lengths. In the third Ca2+ site, Ca2+ is bonded in a trigonal non-coplanar geometry to three equivalent N3- atoms. All Ca–N bond lengths are 2.39 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 4-coordinate geometry to five N3- atoms. There are a spread of Ca–N bond distances ranging from 2.46–3.05 Å. In the fifth Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Ca–N bond distances ranging from 2.37–2.99 Å. In the sixth Ca2+ site, Ca2+ is bonded to six N3- atoms to form distorted CaN6 octahedra that share corners with two equivalent CaN6 octahedra, a cornercorner with one CaN6 pentagonal pyramid, corners with two ReN4 tetrahedra, an edgeedge with one CaN6 pentagonal pyramid, edges with two equivalent ReN4 tetrahedra, and a faceface with one CaN6 pentagonal pyramid. The corner-sharing octahedral tilt angles are 30°. There are a spread of Ca–N bond distances ranging from 2.37–2.84 Å. In the seventh Ca2+ site, Ca2+ is bonded to six N3- atoms to form distorted CaN6 pentagonal pyramids that share a cornercorner with one CaN6 octahedra, corners with two equivalent CaN6 pentagonal pyramids, corners with two equivalent ReN4 tetrahedra, an edgeedge with one CaN6 octahedra, edges with two ReN4 tetrahedra, and a faceface with one CaN6 octahedra. The corner-sharing octahedral tilt angles are 87°. There are a spread of Ca–N bond distances ranging from 2.41–2.77 Å. In the eighth Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven N3- atoms. There are a spread of Ca–N bond distances ranging from 2.48–3.03 Å. In the ninth Ca2+ site, Ca2+ is bonded to five N3- atoms to form distorted CaN5 trigonal bipyramids that share corners with three ReN4 tetrahedra and an edgeedge with one ReN4 tetrahedra. There are a spread of Ca–N bond distances ranging from 2.31–2.66 Å. In the tenth Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Ca–N bond distances ranging from 2.39–2.88 Å. In the eleventh Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Ca–N bond distances ranging from 2.38–2.80 Å. There are three inequivalent Re6+ sites. In the first Re6+ site, Re6+ is bonded to four N3- atoms to form ReN4 tetrahedra that share a cornercorner with one CaN6 octahedra, corners with two equivalent CaN6 pentagonal pyramids, edges with two equivalent CaN6 octahedra, and an edgeedge with one CaN6 pentagonal pyramid. The corner-sharing octahedral tilt angles are 25°. There are a spread of Re–N bond distances ranging from 1.85–1.88 Å. In the second Re6+ site, Re6+ is bonded to four N3- atoms to form ReN4 tetrahedra that share a cornercorner with one CaN5 trigonal bipyramid and an edgeedge with one CaN5 trigonal bipyramid. There is two shorter (1.85 Å) and two longer (1.86 Å) Re–N bond length. In the third Re6+ site, Re6+ is bonded to four N3- atoms to form ReN4 tetrahedra that share a cornercorner with one CaN6 octahedra, corners with two equivalent CaN5 trigonal bipyramids, and an edgeedge with one CaN6 pentagonal pyramid. The corner-sharing octahedral tilt angles are 10°. There is two shorter (1.84 Å) and two longer (1.86 Å) Re–N bond length. There are twelve inequivalent N3- sites. In the first N3- site, N3- is bonded to four Ca2+ and one Re6+ atom to form a mixture of distorted corner and edge-sharing NCa4Re trigonal bipyramids. In the second N3- site, N3- is bonded in a 5-coordinate geometry to four Ca2+ and one Re6+ atom. In the third N3- site, N3- is bonded in a 5-coordinate geometry to four Ca2+ and one Re6+ atom. In the fourth N3- site, N3- is bonded to four Ca2+ and one Re6+ atom to form a mixture of distorted corner and edge-sharing NCa4Re trigonal bipyramids. In the fifth N3- site, N3- is bonded to four Ca2+ and one Re6+ atom to form a mixture of distorted corner and edge-sharing NCa4Re trigonal bipyramids. In the sixth N3- site, N3- is bonded in a 6-coordinate geometry to five Ca2+ and one Re6+ atom. In the seventh N3- site, N3- is bonded in a 4-coordinate geometry to four Ca2+ and one Re6+ atom. In the eighth N3- site, N3- is bonded to four Ca2+ and one Re6+ atom to form a mixture of distorted corner and edge-sharing NCa4Re trigonal bipyramids. In the ninth N3- site, N3- is bonded in a 5-coordinate geometry to four Ca2+ and one Re6+ atom. In the tenth N3- site, N3- is bonded in a 5-coordinate geometry to four Ca2+ and one Re6+ atom. In the eleventh N3- site, N3- is bonded in a 6-coordinate geometry to five Ca2+ and one Re6+ atom. In the twelfth N3- site, N3- is bonded in a 5-coordinate geometry to four Ca2+ and one Re6+ atom.

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2019-03-27. Materials Data on Ca3ReN4 by Materials Project. https://doi.org/10.17188/1696265

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