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DOE OSTI · 1758826

Materials Data on Na3MnS2(O4F)2 by Materials Project

Abstract

Na3MnS2(O4F)2 crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 7-coordinate geometry to six O2- and one F1- atom. There are a spread of Na–O bond distances ranging from 2.40–2.85 Å. The Na–F bond length is 2.42 Å. In the second Na1+ site, Na1+ is bonded to two equivalent O2- and four equivalent F1- atoms to form distorted NaO2F4 pentagonal pyramids that share corners with two equivalent MnO4F2 octahedra, corners with two equivalent SO4 tetrahedra, an edgeedge with one MnO4F2 octahedra, and edges with two equivalent NaO2F4 pentagonal pyramids. The corner-sharing octahedral tilt angles are 54°. Both Na–O bond lengths are 2.38 Å. There are two shorter (2.41 Å) and two longer (2.53 Å) Na–F bond lengths. Mn3+ is bonded to four O2- and two equivalent F1- atoms to form MnO4F2 octahedra that share corners with two equivalent NaO2F4 pentagonal pyramids, corners with four equivalent SO4 tetrahedra, and an edgeedge with one NaO2F4 pentagonal pyramid. There are two shorter (1.97 Å) and two longer (2.21 Å) Mn–O bond lengths. Both Mn–F bond lengths are 1.92 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with two equivalent MnO4F2 octahedra and a cornercorner with one NaO2F4 pentagonal pyramid. The corner-sharing octahedral tilt angles are 44°. There are a spread of S–O bond distances ranging from 1.47–1.53 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Na1+ and one S6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three equivalent Na1+ and one S6+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, one Mn3+, and one S6+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Mn3+, and one S6+ atom. F1- is bonded to three Na1+ and one Mn3+ atom to form a mixture of distorted edge and corner-sharing FNa3Mn tetrahedra.

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2020-09-03. Materials Data on Na3MnS2(O4F)2 by Materials Project. https://doi.org/10.17188/1758826

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