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DOE OSTI · 1308181

Materials Data on Na8NbO6 by Materials Project

Abstract

Na8NbO6 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are sixteen inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with two NbO4 tetrahedra, corners with ten NaO4 tetrahedra, and edges with five NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.36–2.66 Å. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with fourteen NaO4 tetrahedra, an edgeedge with one NbO4 tetrahedra, and edges with three NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.35–2.60 Å. In the third Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with fourteen NaO4 tetrahedra, an edgeedge with one NbO4 tetrahedra, and edges with three NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.36–2.60 Å. In the fourth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with two NbO4 tetrahedra, corners with ten NaO4 tetrahedra, and edges with five NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.37–2.67 Å. In the fifth Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with three equivalent NbO4 tetrahedra, corners with nine NaO4 tetrahedra, and edges with three NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.43–2.47 Å. In the sixth Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with three equivalent NbO4 tetrahedra, corners with nine NaO4 tetrahedra, and edges with three NaO4 tetrahedra. There are three shorter (2.44 Å) and one longer (2.47 Å) Na–O bond lengths. In the seventh Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with two NbO4 tetrahedra, corners with ten NaO4 tetrahedra, and edges with five NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.36–2.67 Å. In the eighth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with fourteen NaO4 tetrahedra, an edgeedge with one NbO4 tetrahedra, and edges with three NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.35–2.60 Å. In the ninth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with fourteen NaO4 tetrahedra, an edgeedge with one NbO4 tetrahedra, and edges with three NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.36–2.59 Å. In the tenth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with two NbO4 tetrahedra, corners with ten NaO4 tetrahedra, and edges with five NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.37–2.67 Å. In the eleventh Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with two NbO4 tetrahedra, corners with ten NaO4 tetrahedra, and edges with five NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.37–2.68 Å. In the twelfth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with fourteen NaO4 tetrahedra, an edgeedge with one NbO4 tetrahedra, and edges with three NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.36–2.60 Å. In the thirteenth Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with three equivalent NbO4 tetrahedra, corners with nine NaO4 tetrahedra, and edges with three NaO4 tetrahedra. There are three shorter (2.44 Å) and one longer (2.47 Å) Na–O bond lengths. In the fourteenth Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with three equivalent NbO4 tetrahedra, corners with nine NaO4 tetrahedra, and edges with three NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.43–2.47 Å. In the fifteenth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with fourteen NaO4 tetrahedra, an edgeedge with one NbO4 tetrahedra, and edges with three NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.35–2.60 Å. In the sixteenth Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with two NbO4 tetrahedra, corners with ten NaO4 tetrahedra, and edges with five NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.36–2.66 Å. There are two inequivalent Nb4+ sites. In the first Nb4+ site, Nb4+ is bonded to four O2- atoms to form NbO4 tetrahedra that share corners with twelve NaO4 tetrahedra and edges with three NaO4 tetrahedra. There is one shorter (1.89 Å) and three longer (1.90 Å) Nb–O bond length. In the second Nb4+ site, Nb4+ is bonded to four O2- atoms to form NbO4 tetrahedra that share corners with twelve NaO4 tetrahedra and edges with three NaO4 tetrahedra. There is three shorter (1.90 Å) and one longer (1.93 Å) Nb–O bond length. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded to four Na1+ and one Nb4+ atom to form distorted ONa4Nb trigonal bipyramids that share corners with two ONa7 pentagonal bipyramids, corners with six ONa4Nb trigonal bipyramids, and edges with two ONa7 pentagonal bipyramids. In the second O2- site, O2- is bonded to four Na1+ and one Nb4+ atom to form distorted ONa4Nb trigonal bipyramids that share corners with two ONa7 pentagonal bipyramids, corners with six ONa4Nb trigonal bipyramids, and edges with two ONa7 pentagonal bipyramids. In the third O2- site, O2- is bonded to seven Na1+ atoms to form distorted ONa7 pentagonal bipyramids that share corners with three ONa4Nb trigonal bipyramids, edges with three equivalent ONa7 pentagonal bipyramids, and edges with three ONa4Nb trigonal bipyramids. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to six Na1+ and one Nb4+ atom. In the fifth O2- site, O2- is bonded in a 7-coordinate geometry to six Na1+ and one Nb4+ atom. In the sixth O2- site, O2- is bonded to seven Na1+ atoms to form distorted ONa7 pentagonal bipyramids that share corners with three ONa4Nb trigonal bipyramids, edges with three equivalent ONa7 pentagonal bipyramids, and edges with three ONa4Nb trigonal bipyramids. In the seventh O2- site, O2- is bonded to four Na1+ and one Nb4+ atom to form distorted ONa4Nb trigonal bipyramids that share corners with two ONa7 pentagonal bipyramids, corners with six ONa4Nb trigonal bipyramids, and edges with two ONa7 pentagonal bipyramids. In the eighth O2- site, O2- is bonded to four Na1+ and one Nb4+ atom to form distorted ONa4Nb trigonal bipyramids that share corners with two ONa7 pentagonal bipyramids, corners with six ONa4Nb trigonal bipyramids, and edges with two ONa7 pentagonal bipyramids. In the ninth O2- site, O2- is bonded to four Na1+ and one Nb4+ atom to form distorted ONa4Nb trigonal bipyramids that share corners with two ONa7 pentagonal bipyramids, corners with six ONa4Nb trigonal bipyramids, and edges with two ONa7 pentagonal bipyramids. In the tenth O2- site, O2- is bonded to seven Na1+ atoms to form distorted ONa7 pentagonal bipyramids that share corners with three ONa4Nb trigonal bipyramids, edges with three equivalent ONa7 pentagonal bipyramids, and edges with three ONa4Nb trigonal bipyramids. In the eleventh O2- site, O2- is bonded to seven Na1+ atoms to form distorted ONa7 pentagonal bipyramids that share corners with three ONa4Nb trigonal bipyramids, edges with three equivalent ONa7 pentagonal bipyramids, and edges with three ONa4Nb trigonal bipyramids. In the twelfth O2- site, O2- is bonded to four Na1+ and one Nb4+ atom to form distorted ONa4Nb trigonal bipyramids that share corners with two ONa7 pentagonal bipyramids, corners with six ONa4Nb trigonal bipyramids, and edges with two ONa7 pentagonal bipyramids.

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2020-05-02. Materials Data on Na8NbO6 by Materials Project. https://doi.org/10.17188/1308181

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