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DOE OSTI · 1757029

Materials Data on KBi3S5 by Materials Project

Abstract

KBi3S5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. K1+ is bonded to five S2- atoms to form distorted KS5 square pyramids that share corners with five BiS6 octahedra, edges with six BiS6 octahedra, and edges with two equivalent KS5 square pyramids. The corner-sharing octahedra tilt angles range from 3–20°. There are a spread of K–S bond distances ranging from 3.20–3.39 Å. There are three inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to six S2- atoms to form BiS6 octahedra that share corners with two equivalent BiS6 octahedra, a cornercorner with one KS5 square pyramid, edges with nine BiS6 octahedra, and edges with two equivalent KS5 square pyramids. The corner-sharing octahedral tilt angles are 2°. There are a spread of Bi–S bond distances ranging from 2.72–3.04 Å. In the second Bi3+ site, Bi3+ is bonded to six S2- atoms to form BiS6 octahedra that share corners with three BiS6 octahedra, edges with seven BiS6 octahedra, and edges with two equivalent KS5 square pyramids. The corner-sharing octahedra tilt angles range from 2–7°. There are a spread of Bi–S bond distances ranging from 2.78–2.94 Å. In the third Bi3+ site, Bi3+ is bonded to six S2- atoms to form BiS6 octahedra that share a cornercorner with one BiS6 octahedra, corners with four equivalent KS5 square pyramids, edges with six BiS6 octahedra, and edges with two equivalent KS5 square pyramids. The corner-sharing octahedral tilt angles are 7°. There are a spread of Bi–S bond distances ranging from 2.67–3.11 Å. There are five inequivalent S2- sites. In the first S2- site, S2- is bonded to two equivalent K1+ and three Bi3+ atoms to form distorted SK2Bi3 square pyramids that share a cornercorner with one SKBi5 octahedra, corners with four equivalent SK2Bi3 square pyramids, edges with two equivalent SKBi5 octahedra, and edges with four SK2Bi3 square pyramids. The corner-sharing octahedral tilt angles are 0°. In the second S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Bi3+ atoms. In the third S2- site, S2- is bonded to one K1+ and five Bi3+ atoms to form SKBi5 octahedra that share a cornercorner with one SK2Bi3 square pyramid, edges with four equivalent SKBi5 octahedra, and edges with four SK2Bi3 square pyramids. In the fourth S2- site, S2- is bonded in a distorted T-shaped geometry to three Bi3+ atoms. In the fifth S2- site, S2- is bonded to two equivalent K1+ and three Bi3+ atoms to form SK2Bi3 square pyramids that share corners with four equivalent SK2Bi3 square pyramids, edges with two equivalent SKBi5 octahedra, and edges with four SK2Bi3 square pyramids.

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2020-09-03. Materials Data on KBi3S5 by Materials Project. https://doi.org/10.17188/1757029

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