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DOE OSTI · 1193948

Materials Data on Na4W(NO)2 by Materials Project

Abstract

Na4W(NO)2 is Aluminum carbonitride-derived structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with four NaN4O square pyramids, corners with four equivalent NaN2O2 tetrahedra, corners with four equivalent WN2O2 tetrahedra, and edges with two equivalent NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.32–2.43 Å. In the second Na1+ site, Na1+ is bonded to four N3- and one O2- atom to form distorted NaN4O square pyramids that share corners with three equivalent NaN4O square pyramids, a cornercorner with one WN2O2 tetrahedra, corners with five NaO4 tetrahedra, edges with five NaN4O square pyramids, an edgeedge with one NaN2O2 tetrahedra, and edges with two equivalent WN2O2 tetrahedra. There are a spread of Na–N bond distances ranging from 2.48–2.68 Å. The Na–O bond length is 2.53 Å. In the third Na1+ site, Na1+ is bonded to four N3- and one O2- atom to form distorted NaN4O square pyramids that share corners with three equivalent NaN4O square pyramids, corners with three NaO4 tetrahedra, corners with three equivalent WN2O2 tetrahedra, edges with five NaN4O square pyramids, an edgeedge with one WN2O2 tetrahedra, and edges with two equivalent NaN2O2 tetrahedra. There are a spread of Na–N bond distances ranging from 2.46–2.54 Å. The Na–O bond length is 2.91 Å. In the fourth Na1+ site, Na1+ is bonded to two N3- and two O2- atoms to form NaN2O2 tetrahedra that share corners with four NaN4O square pyramids, corners with four equivalent NaO4 tetrahedra, corners with four equivalent WN2O2 tetrahedra, and edges with three NaN4O square pyramids. Both Na–N bond lengths are 2.41 Å. There are one shorter (2.37 Å) and one longer (2.40 Å) Na–O bond lengths. W6+ is bonded to two N3- and two O2- atoms to form WN2O2 tetrahedra that share corners with four NaN4O square pyramids, corners with eight NaO4 tetrahedra, and edges with three NaN4O square pyramids. Both W–N bond lengths are 1.85 Å. Both W–O bond lengths are 1.91 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded to five Na1+ and one W6+ atom to form distorted NNa5W octahedra that share corners with two equivalent NNa5W octahedra, corners with two equivalent ONa3W tetrahedra, and edges with six NNa5W octahedra. The corner-sharing octahedra tilt angles range from 19–38°. In the second N3- site, N3- is bonded to five Na1+ and one W6+ atom to form distorted NNa5W octahedra that share corners with two equivalent NNa5W octahedra, corners with two equivalent ONa3W tetrahedra, and edges with six NNa5W octahedra. The corner-sharing octahedra tilt angles range from 19–38°. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one W6+ atom. In the second O2- site, O2- is bonded to three Na1+ and one W6+ atom to form distorted ONa3W tetrahedra that share corners with four NNa5W octahedra and an edgeedge with one ONa3W tetrahedra. The corner-sharing octahedra tilt angles range from 62–69°.

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BibTeXRIS

2020-07-14. Materials Data on Na4W(NO)2 by Materials Project. https://doi.org/10.17188/1193948

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