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DOE OSTI · 1723426

Materials Data on Na9(WO3)13 by Materials Project

Abstract

Na9(WO3)13 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are five inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with eleven NaO12 cuboctahedra, faces with two equivalent NaO12 cuboctahedra, and faces with eight WO6 octahedra. There are a spread of Na–O bond distances ranging from 2.77–2.80 Å. In the second Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with seven NaO12 cuboctahedra, faces with four NaO12 cuboctahedra, and faces with eight WO6 octahedra. There are a spread of Na–O bond distances ranging from 2.76–2.81 Å. In the third Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with ten NaO12 cuboctahedra, faces with four equivalent NaO12 cuboctahedra, and faces with eight WO6 octahedra. There are ten shorter (2.78 Å) and two longer (2.79 Å) Na–O bond lengths. In the fourth Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with nine NaO12 cuboctahedra, faces with three NaO12 cuboctahedra, and faces with eight WO6 octahedra. There are a spread of Na–O bond distances ranging from 2.78–2.81 Å. In the fifth Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with eight NaO12 cuboctahedra, faces with four NaO12 cuboctahedra, and faces with eight WO6 octahedra. There are a spread of Na–O bond distances ranging from 2.73–2.82 Å. There are seven inequivalent W+5.31+ sites. In the first W+5.31+ site, W+5.31+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six WO6 octahedra and faces with five NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of W–O bond distances ranging from 1.85–2.00 Å. In the second W+5.31+ site, W+5.31+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six WO6 octahedra and faces with six NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–5°. There are a spread of W–O bond distances ranging from 1.89–1.97 Å. In the third W+5.31+ site, W+5.31+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six WO6 octahedra and faces with five NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–2°. There are a spread of W–O bond distances ranging from 2.01–2.07 Å. In the fourth W+5.31+ site, W+5.31+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six WO6 octahedra and faces with six NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–2°. There are four shorter (2.02 Å) and two longer (2.06 Å) W–O bond lengths. In the fifth W+5.31+ site, W+5.31+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six WO6 octahedra and faces with five NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of W–O bond distances ranging from 1.91–2.04 Å. In the sixth W+5.31+ site, W+5.31+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six WO6 octahedra and faces with six NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–6°. There are a spread of W–O bond distances ranging from 1.88–2.01 Å. In the seventh W+5.31+ site, W+5.31+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six WO6 octahedra and faces with six NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are a spread of W–O bond distances ranging from 1.91–2.02 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted square co-planar geometry to two equivalent Na1+ and two equivalent W+5.31+ atoms. In the second O2- site, O2- is bonded to three Na1+ and two W+5.31+ atoms to form distorted ONa3W2 square pyramids that share a cornercorner with one ONa4W2 octahedra, corners with twelve ONa3W2 square pyramids, edges with four ONa3W2 square pyramids, and faces with four ONa3W2 square pyramids. The corner-sharing octahedral tilt angles are 61°. In the third O2- site, O2- is bonded to three Na1+ and two W+5.31+ atoms to form a mixture of distorted edge, face, and corner-sharing ONa3W2 square pyramids. In the fourth O2- site, O2- is bonded to three Na1+ and two W+5.31+ atoms to form distorted ONa3W2 square pyramids that share a cornercorner with one ONa4W2 octahedra, corners with twelve ONa3W2 square pyramids, edges with four ONa3W2 square pyramids, and faces with four ONa3W2 square pyramids. The corner-sharing octahedral tilt angles are 61°. In the fifth O2- site, O2- is bonded to three Na1+ and two W+5.31+ atoms to form a mixture of distorted edge, face, and corner-sharing ONa3W2 square pyramids. In the sixth O2- site, O2- is bonded to three Na1+ and two W+5.31+ atoms to form a mixture of distorted edge, face, and corner-sharing ONa3W2 square pyramids. In the seventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+ and two W+5.31+ atoms. In the eighth O2- site, O2- is bonded to three Na1+ and two W+5.31+ atoms to form distorted ONa3W2 square pyramids that share a cornercorner with one ONa4W2 octahedra, corners with fifteen ONa3W2 square pyramids, edges with five ONa3W2 square pyramids, a faceface with one ONa4W2 octahedra, and faces with three ONa3W2 square pyramids. The corner-sharing octahedral tilt angles are 60°. In the ninth O2- site, O2- is bonded to three Na1+ and two W+5.31+ atoms to form distorted ONa3W2 square pyramids that share corners with seventeen ONa3W2 square pyramids, edges with two equivalent ONa4W2 octahedra, edges with four ONa3W2 square pyramids, and faces with four ONa3W2 square pyramids. In the tenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+ and two W+5.31+ atoms. In the eleventh O2- site, O2- is bonded to three equivalent Na1+ and two W+5.31+ atoms to form a mixture of distorted edge, face, and corner-sharing ONa3W2 square pyramids. In the twelfth O2- site, O2- is bonded to three Na1+ and two W+5.31+ atoms to form distorted ONa3W2 square pyramids that share a cornercorner with one ONa4W2 octahedra, corners with seventeen ONa3W2 square pyramids, edges with five ONa3W2 square pyramids, a faceface with one ONa4W2 octahedra, and faces with three ONa3W2 square pyramids. The corner-sharing octahedral tilt angles are 60°. In the thirteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+ and two W+5.31+ atoms. In the fourteenth O2- site, O2- is bonded to four Na1+ and two equivalent W+5.31+ atoms to form distorted ONa4W2 octahedra that share corners with two equivalent ONa4W2 octahedra, corners with sixteen ONa3W2 square pyramids, edges with four equivalent ONa3W2 square pyramids, and faces with eight ONa3W2 square pyramids. The corner-sharing octahedral tilt angles are 0°.

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2020-05-02. Materials Data on Na9(WO3)13 by Materials Project. https://doi.org/10.17188/1723426

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