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DOE OSTI · 1269824

Materials Data on Na6PbO5 by Materials Project

Abstract

Na6PbO5 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.28–2.70 Å. In the second Na1+ site, Na1+ is bonded to five O2- atoms to form distorted NaO5 trigonal bipyramids that share corners with four equivalent NaO4 tetrahedra, a cornercorner with one NaO5 trigonal bipyramid, a cornercorner with one PbO5 trigonal bipyramid, edges with two equivalent NaO4 tetrahedra, edges with two equivalent NaO5 trigonal bipyramids, and edges with two equivalent PbO5 trigonal bipyramids. There are three shorter (2.48 Å) and two longer (2.52 Å) Na–O bond lengths. In the third Na1+ site, Na1+ is bonded to four equivalent O2- atoms to form distorted NaO4 tetrahedra that share corners with four equivalent NaO5 trigonal bipyramids, corners with four equivalent PbO5 trigonal bipyramids, edges with two equivalent NaO4 tetrahedra, and edges with two equivalent NaO5 trigonal bipyramids. There are two shorter (2.28 Å) and two longer (2.33 Å) Na–O bond lengths. Pb4+ is bonded to five O2- atoms to form distorted PbO5 trigonal bipyramids that share corners with eight equivalent NaO4 tetrahedra, corners with two equivalent NaO5 trigonal bipyramids, and edges with four equivalent NaO5 trigonal bipyramids. There are one shorter (2.15 Å) and four longer (2.21 Å) Pb–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to four Na1+ and one Pb4+ atom. In the second O2- site, O2- is bonded to six Na1+ and one Pb4+ atom to form a mixture of distorted face, edge, and corner-sharing ONa6Pb pentagonal bipyramids.

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2020-07-16. Materials Data on Na6PbO5 by Materials Project. https://doi.org/10.17188/1269824

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36 MATERIALS SCIENCE↗