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DOE OSTI · 1269400

Materials Data on Cs2MnBi2S5 by Materials Project

Abstract

Cs2Bi2MnS5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of Cs–S bond distances ranging from 3.54–3.62 Å. In the second Cs1+ site, Cs1+ is bonded to six S2- atoms to form distorted CsS6 octahedra that share corners with five BiS6 octahedra, corners with three equivalent MnS4 tetrahedra, edges with four equivalent CsS6 octahedra, edges with five BiS6 octahedra, and an edgeedge with one MnS4 tetrahedra. The corner-sharing octahedra tilt angles range from 1–59°. There are a spread of Cs–S bond distances ranging from 3.48–3.65 Å. Mn2+ is bonded to four S2- atoms to form MnS4 tetrahedra that share corners with three equivalent CsS6 octahedra, corners with two equivalent MnS4 tetrahedra, an edgeedge with one CsS6 octahedra, and edges with four BiS6 octahedra. The corner-sharing octahedra tilt angles range from 1–27°. There are a spread of Mn–S bond distances ranging from 2.40–2.46 Å. There are two inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to six S2- atoms to form BiS6 octahedra that share a cornercorner with one BiS6 octahedra, corners with two equivalent CsS6 octahedra, edges with three equivalent CsS6 octahedra, edges with four BiS6 octahedra, and edges with two equivalent MnS4 tetrahedra. The corner-sharing octahedra tilt angles range from 11–36°. There are a spread of Bi–S bond distances ranging from 2.66–3.25 Å. In the second Bi3+ site, Bi3+ is bonded to six S2- atoms to form BiS6 octahedra that share a cornercorner with one BiS6 octahedra, corners with three equivalent CsS6 octahedra, edges with two equivalent CsS6 octahedra, edges with four BiS6 octahedra, and edges with two equivalent MnS4 tetrahedra. The corner-sharing octahedra tilt angles range from 1–59°. There are a spread of Bi–S bond distances ranging from 2.78–2.98 Å. There are five inequivalent S2- sites. In the first S2- site, S2- is bonded to three Cs1+, one Mn2+, and two equivalent Bi3+ atoms to form distorted SCs3MnBi2 octahedra that share a cornercorner with one SCs3Bi3 octahedra, corners with four equivalent SCs2Bi3 square pyramids, edges with four SCs3MnBi2 octahedra, and edges with two equivalent SCs2Bi3 square pyramids. The corner-sharing octahedral tilt angles are 16°. In the second S2- site, S2- is bonded to three equivalent Cs1+ and three Bi3+ atoms to form SCs3Bi3 octahedra that share a cornercorner with one SCs3MnBi2 octahedra, edges with six SCs3MnBi2 octahedra, and edges with two equivalent SCs2Bi3 square pyramids. The corner-sharing octahedral tilt angles are 16°. In the third S2- site, S2- is bonded in a 2-coordinate geometry to two equivalent Cs1+, two equivalent Mn2+, and two Bi3+ atoms. In the fourth S2- site, S2- is bonded to two equivalent Cs1+ and three Bi3+ atoms to form distorted SCs2Bi3 square pyramids that share corners with four equivalent SCs3MnBi2 octahedra, edges with four SCs3MnBi2 octahedra, and edges with two equivalent SCs2Bi3 square pyramids. The corner-sharing octahedra tilt angles range from 4–47°. In the fifth S2- site, S2- is bonded in a 6-coordinate geometry to three equivalent Cs1+, one Mn2+, and two equivalent Bi3+ atoms.

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2020-04-30. Materials Data on Cs2MnBi2S5 by Materials Project. https://doi.org/10.17188/1269400

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