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DOE OSTI · 1740187

Materials Data on SrEu4Se5 by Materials Project

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Abstract

SrEu4Se5 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Sr2+ is bonded to six Se2- atoms to form SrSe6 octahedra that share corners with six EuSe6 octahedra, edges with two equivalent SrSe6 octahedra, and edges with ten EuSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. All Sr–Se bond lengths are 3.11 Å. There are two inequivalent Eu2+ sites. In the first Eu2+ site, Eu2+ is bonded to six Se2- atoms to form EuSe6 octahedra that share a cornercorner with one SrSe6 octahedra, corners with five EuSe6 octahedra, edges with two equivalent SrSe6 octahedra, and edges with ten EuSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are one shorter (3.08 Å) and five longer (3.10 Å) Eu–Se bond lengths. In the second Eu2+ site, Eu2+ is bonded to six Se2- atoms to form EuSe6 octahedra that share corners with two equivalent SrSe6 octahedra, corners with four EuSe6 octahedra, edges with three equivalent SrSe6 octahedra, and edges with nine EuSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are two shorter (3.08 Å) and four longer (3.10 Å) Eu–Se bond lengths. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to one Sr2+ and five Eu2+ atoms to form a mixture of edge and corner-sharing SeSrEu5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second Se2- site, Se2- is bonded to two equivalent Sr2+ and four Eu2+ atoms to form a mixture of edge and corner-sharing SeSr2Eu4 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third Se2- site, Se2- is bonded to six Eu2+ atoms to form a mixture of edge and corner-sharing SeEu6 octahedra. The corner-sharing octahedral tilt angles are 0°.

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36 MATERIALS SCIENCEcrystal structureEu-Se-SrSrEu4Se5

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2020-05-03. Materials Data on SrEu4Se5 by Materials Project. https://doi.org/10.17188/1740187

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