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DOE OSTI · 1308046

Materials Data on BaMnS2 by Materials Project

Abstract

BaMnS2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ba2+ is bonded to seven S2- atoms to form distorted BaS7 pentagonal bipyramids that share corners with four equivalent BaS7 pentagonal bipyramids, corners with four equivalent MnS4 tetrahedra, edges with four equivalent BaS7 pentagonal bipyramids, edges with five equivalent MnS4 tetrahedra, and faces with two equivalent BaS7 pentagonal bipyramids. There are a spread of Ba–S bond distances ranging from 3.22–3.39 Å. Mn2+ is bonded to four S2- atoms to form MnS4 tetrahedra that share corners with four equivalent BaS7 pentagonal bipyramids, corners with four equivalent MnS4 tetrahedra, and edges with five equivalent BaS7 pentagonal bipyramids. There are a spread of Mn–S bond distances ranging from 2.40–2.43 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to four equivalent Ba2+ and two equivalent Mn2+ atoms to form distorted SBa4Mn2 octahedra that share corners with four equivalent SBa4Mn2 octahedra, corners with eight equivalent SBa3Mn2 square pyramids, edges with two equivalent SBa4Mn2 octahedra, edges with four equivalent SBa3Mn2 square pyramids, and faces with two equivalent SBa4Mn2 octahedra. The corner-sharing octahedral tilt angles are 64°. In the second S2- site, S2- is bonded to three equivalent Ba2+ and two equivalent Mn2+ atoms to form distorted SBa3Mn2 square pyramids that share corners with eight equivalent SBa4Mn2 octahedra, edges with four equivalent SBa4Mn2 octahedra, and edges with four equivalent SBa3Mn2 square pyramids. The corner-sharing octahedra tilt angles range from 29–67°.

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2020-08-03. Materials Data on BaMnS2 by Materials Project. https://doi.org/10.17188/1308046

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