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DOE OSTI · 1709643

Materials Data on Zr5N5O2 by Materials Project

Abstract

Zr5N5O2 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are five inequivalent Zr+3.80+ sites. In the first Zr+3.80+ site, Zr+3.80+ is bonded to five N3- and one O2- atom to form ZrN5O octahedra that share corners with three ZrN5O octahedra, corners with four equivalent ZrN5O2 pentagonal bipyramids, edges with five ZrN5O octahedra, and an edgeedge with one ZrN5O2 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 2–59°. There are two shorter (2.20 Å) and three longer (2.25 Å) Zr–N bond lengths. The Zr–O bond length is 2.20 Å. In the second Zr+3.80+ site, Zr+3.80+ is bonded in a 7-coordinate geometry to five N3- and two equivalent O2- atoms. There are a spread of Zr–N bond distances ranging from 2.30–2.45 Å. Both Zr–O bond lengths are 2.25 Å. In the third Zr+3.80+ site, Zr+3.80+ is bonded to five N3- and two equivalent O2- atoms to form distorted ZrN5O2 pentagonal bipyramids that share corners with eight ZrN5O octahedra, edges with four ZrN5O octahedra, and faces with two equivalent ZrN5O2 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 21–70°. There are a spread of Zr–N bond distances ranging from 2.29–2.43 Å. Both Zr–O bond lengths are 2.26 Å. In the fourth Zr+3.80+ site, Zr+3.80+ is bonded to five N3- and one O2- atom to form ZrN5O octahedra that share corners with three ZrN5O octahedra, corners with two equivalent ZrN5O2 pentagonal bipyramids, and edges with five ZrN5O octahedra. The corner-sharing octahedra tilt angles range from 2–59°. There are a spread of Zr–N bond distances ranging from 2.20–2.25 Å. The Zr–O bond length is 2.19 Å. In the fifth Zr+3.80+ site, Zr+3.80+ is bonded to four N3- and two O2- atoms to form ZrN4O2 octahedra that share corners with two ZrN5O octahedra, corners with two equivalent ZrN5O2 pentagonal bipyramids, edges with two equivalent ZrN4O2 octahedra, and edges with three equivalent ZrN5O2 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 59°. All Zr–N bond lengths are 2.24 Å. Both Zr–O bond lengths are 2.15 Å. There are five inequivalent N3- sites. In the first N3- site, N3- is bonded in a rectangular see-saw-like geometry to four Zr+3.80+ atoms. In the second N3- site, N3- is bonded to five Zr+3.80+ atoms to form distorted NZr5 trigonal bipyramids that share corners with four equivalent OZr4 tetrahedra, corners with six NZr5 trigonal bipyramids, edges with three OZr4 tetrahedra, and edges with six NZr5 trigonal bipyramids. In the third N3- site, N3- is bonded to five Zr+3.80+ atoms to form distorted NZr5 trigonal bipyramids that share corners with five OZr4 tetrahedra, corners with four NZr5 trigonal bipyramids, an edgeedge with one OZr4 tetrahedra, and edges with five NZr5 trigonal bipyramids. In the fourth N3- site, N3- is bonded to five Zr+3.80+ atoms to form distorted NZr5 trigonal bipyramids that share corners with five OZr4 tetrahedra, corners with four NZr5 trigonal bipyramids, an edgeedge with one OZr4 tetrahedra, and edges with five NZr5 trigonal bipyramids. In the fifth N3- site, N3- is bonded to five Zr+3.80+ atoms to form distorted NZr5 trigonal bipyramids that share corners with four equivalent OZr4 tetrahedra, corners with six NZr5 trigonal bipyramids, edges with three OZr4 tetrahedra, and edges with six NZr5 trigonal bipyramids. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four Zr+3.80+ atoms to form distorted OZr4 tetrahedra that share corners with three OZr4 tetrahedra, corners with nine NZr5 trigonal bipyramids, and edges with four NZr5 trigonal bipyramids. In the second O2- site, O2- is bonded to four Zr+3.80+ atoms to form distorted OZr4 tetrahedra that share corners with three OZr4 tetrahedra, corners with nine NZr5 trigonal bipyramids, and edges with four NZr5 trigonal bipyramids.

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2020-05-02. Materials Data on Zr5N5O2 by Materials Project. https://doi.org/10.17188/1709643

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