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DOE OSTI · 1747069

Materials Data on Na4(WO3)5 by Materials Project

Abstract

Na4(WO3)5 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with ten NaO12 cuboctahedra, faces with four NaO12 cuboctahedra, and faces with eight WO6 octahedra. There are a spread of Na–O bond distances ranging from 2.74–2.83 Å. In the second Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with nine NaO12 cuboctahedra, faces with five NaO12 cuboctahedra, and faces with eight WO6 octahedra. There are a spread of Na–O bond distances ranging from 2.76–2.81 Å. There are three inequivalent W+5.20+ sites. In the first W+5.20+ site, W+5.20+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six WO6 octahedra and faces with seven NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are a spread of W–O bond distances ranging from 1.87–2.01 Å. In the second W+5.20+ site, W+5.20+ 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 0–5°. There are a spread of W–O bond distances ranging from 1.96–2.06 Å. In the third W+5.20+ site, W+5.20+ 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 octahedral tilt angles are 3°. There are four shorter (1.99 Å) and two longer (2.04 Å) W–O bond lengths. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to four Na1+ and two equivalent W+5.20+ atoms to form distorted ONa4W2 octahedra that share corners with four equivalent ONa4W2 octahedra, corners with sixteen ONa3W2 square pyramids, edges with four ONa3W2 square pyramids, faces with four ONa4W2 octahedra, and faces with four ONa3W2 square pyramids. The corner-sharing octahedral tilt angles are 60°. In the second O2- site, O2- is bonded to three Na1+ and two W+5.20+ atoms to form distorted ONa3W2 square pyramids that share corners with six ONa4W2 octahedra, corners with thirteen ONa3W2 square pyramids, an edgeedge with one ONa4W2 octahedra, edges with four ONa3W2 square pyramids, faces with three ONa4W2 octahedra, and a faceface with one ONa3W2 square pyramid. The corner-sharing octahedra tilt angles range from 2–62°. In the third O2- site, O2- is bonded to three Na1+ and two W+5.20+ atoms to form distorted ONa3W2 square pyramids that share corners with seven ONa4W2 octahedra, corners with eleven ONa3W2 square pyramids, an edgeedge with one ONa4W2 octahedra, edges with four ONa3W2 square pyramids, a faceface with one ONa4W2 octahedra, and faces with three ONa3W2 square pyramids. The corner-sharing octahedra tilt angles range from 0–61°. In the fourth O2- site, O2- is bonded to four Na1+ and two W+5.20+ atoms to form distorted ONa4W2 octahedra that share corners with six ONa4W2 octahedra, corners with fourteen ONa3W2 square pyramids, edges with two equivalent ONa4W2 octahedra, edges with two equivalent ONa3W2 square pyramids, faces with two equivalent ONa4W2 octahedra, and faces with six ONa3W2 square pyramids. The corner-sharing octahedra tilt angles range from 1–60°. In the fifth O2- site, O2- is bonded to three Na1+ and two W+5.20+ atoms to form distorted ONa3W2 square pyramids that share corners with four ONa4W2 octahedra, corners with thirteen ONa3W2 square pyramids, edges with two equivalent ONa4W2 octahedra, edges with four ONa3W2 square pyramids, faces with two equivalent ONa4W2 octahedra, and faces with two equivalent ONa3W2 square pyramids. The corner-sharing octahedra tilt angles range from 2–62°. In the sixth O2- site, O2- is bonded in a distorted square co-planar geometry to two equivalent Na1+ and two equivalent W+5.20+ atoms.

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2020-04-29. Materials Data on Na4(WO3)5 by Materials Project. https://doi.org/10.17188/1747069

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