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DOE OSTI · 1726489

Materials Data on Eu2BiS4 by Materials Project

Abstract

Eu2BiS4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Eu+2.50+ sites. In the first Eu+2.50+ site, Eu+2.50+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Eu–S bond distances ranging from 2.94–3.43 Å. In the second Eu+2.50+ site, Eu+2.50+ is bonded to seven S2- atoms to form distorted EuS7 pentagonal bipyramids that share corners with three equivalent BiS6 octahedra, edges with two equivalent BiS6 octahedra, and edges with four equivalent EuS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 7–49°. There are a spread of Eu–S bond distances ranging from 2.85–3.03 Å. Bi3+ is bonded to six S2- atoms to form BiS6 octahedra that share corners with three equivalent EuS7 pentagonal bipyramids, edges with four equivalent BiS6 octahedra, and edges with two equivalent EuS7 pentagonal bipyramids. There are a spread of Bi–S bond distances ranging from 2.67–3.04 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to three Eu+2.50+ and two equivalent Bi3+ atoms. In the second S2- site, S2- is bonded to four Eu+2.50+ and one Bi3+ atom to form distorted SEu4Bi trigonal bipyramids that share corners with three equivalent SEu3Bi3 octahedra, corners with six equivalent SEu5 square pyramids, edges with three equivalent SEu3Bi3 octahedra, edges with two equivalent SEu5 square pyramids, and edges with two equivalent SEu4Bi trigonal bipyramids. The corner-sharing octahedra tilt angles range from 4–30°. In the third S2- site, S2- is bonded to five Eu+2.50+ atoms to form distorted SEu5 square pyramids that share corners with four equivalent SEu3Bi3 octahedra, corners with six equivalent SEu4Bi trigonal bipyramids, edges with four equivalent SEu5 square pyramids, edges with two equivalent SEu4Bi trigonal bipyramids, and a faceface with one SEu3Bi3 octahedra. The corner-sharing octahedra tilt angles range from 55–60°. In the fourth S2- site, S2- is bonded to three Eu+2.50+ and three equivalent Bi3+ atoms to form SEu3Bi3 octahedra that share corners with four equivalent SEu5 square pyramids, corners with three equivalent SEu4Bi trigonal bipyramids, edges with four equivalent SEu3Bi3 octahedra, edges with three equivalent SEu4Bi trigonal bipyramids, and a faceface with one SEu5 square pyramid.

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2020-05-02. Materials Data on Eu2BiS4 by Materials Project. https://doi.org/10.17188/1726489

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