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DOE OSTI · 1305908

Materials Data on Na10Mn2O9 by Materials Project

Abstract

Na10Mn2O9 is Aluminum carbonitride-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are ten inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 4-coordinate geometry to three O2- atoms. There are a spread of Na–O bond distances ranging from 2.19–2.53 Å. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with three equivalent MnO4 tetrahedra, corners with four NaO4 tetrahedra, a cornercorner with one NaO4 trigonal pyramid, and an edgeedge with one NaO4 trigonal pyramid. There are a spread of Na–O bond distances ranging from 2.26–2.41 Å. In the third Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with two MnO4 tetrahedra, corners with eight NaO4 tetrahedra, an edgeedge with one MnO4 tetrahedra, and an edgeedge with one NaO4 trigonal pyramid. There are a spread of Na–O bond distances ranging from 2.34–2.59 Å. In the fourth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with two MnO4 tetrahedra, corners with eight NaO4 tetrahedra, an edgeedge with one MnO4 tetrahedra, and an edgeedge with one NaO4 trigonal pyramid. There are a spread of Na–O bond distances ranging from 2.21–2.55 Å. In the fifth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share corners with two MnO4 tetrahedra, corners with eight NaO4 tetrahedra, an edgeedge with one MnO4 tetrahedra, and an edgeedge with one NaO4 trigonal pyramid. There are a spread of Na–O bond distances ranging from 2.34–2.44 Å. In the sixth Na1+ site, Na1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.24–2.45 Å. In the seventh Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share a cornercorner with one MnO4 tetrahedra, corners with four NaO4 tetrahedra, and an edgeedge with one MnO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.26–2.35 Å. In the eighth Na1+ site, Na1+ is bonded in a 3-coordinate geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.23–2.78 Å. In the ninth Na1+ site, Na1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.25–2.53 Å. In the tenth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 trigonal pyramids that share a cornercorner with one NaO4 tetrahedra, corners with two MnO4 tetrahedra, an edgeedge with one MnO4 tetrahedra, and edges with four NaO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.24–2.49 Å. There are two inequivalent Mn4+ sites. In the first Mn4+ site, Mn4+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with seven NaO4 tetrahedra, a cornercorner with one NaO4 trigonal pyramid, and an edgeedge with one NaO4 trigonal pyramid. There are a spread of Mn–O bond distances ranging from 1.80–1.84 Å. In the second Mn4+ site, Mn4+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with three NaO4 tetrahedra, a cornercorner with one NaO4 trigonal pyramid, and edges with four NaO4 tetrahedra. There are a spread of Mn–O bond distances ranging from 1.80–1.89 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to six Na1+ atoms to form a mixture of distorted corner and edge-sharing ONa6 octahedra. In the second O2- site, O2- is bonded in a 5-coordinate geometry to four Na1+ and one Mn4+ atom. In the third O2- site, O2- is bonded to four Na1+ and one Mn4+ atom to form a mixture of distorted corner and edge-sharing ONa4Mn trigonal bipyramids. The corner-sharing octahedra tilt angles range from 54–60°. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to four Na1+ and one Mn4+ atom. In the fifth O2- site, O2- is bonded in a 5-coordinate geometry to four Na1+ and one Mn4+ atom. In the sixth O2- site, O2- is bonded to four Na1+ and one Mn4+ atom to form distorted corner-sharing ONa4Mn trigonal bipyramids. The corner-sharing octahedral tilt angles are 49°. In the seventh O2- site, O2- is bonded in a 5-coordinate geometry to four Na1+ and one Mn4+ atom. In the eighth O2- site, O2- is bonded in a 5-coordinate geometry to four Na1+ and one Mn4+ atom. In the ninth O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one Mn4+ atom.

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2020-05-23. Materials Data on Na10Mn2O9 by Materials Project. https://doi.org/10.17188/1305908

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36 MATERIALS SCIENCE↗