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DOE OSTI · 1681669

Materials Data on Eu11(ZnSb2)6 by Materials Project

Abstract

Eu11Zn6Sb12 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are six inequivalent Eu+2.18+ sites. In the first Eu+2.18+ site, Eu+2.18+ is bonded in a 6-coordinate geometry to eight Sb3- atoms. There are a spread of Eu–Sb bond distances ranging from 3.37–3.82 Å. In the second Eu+2.18+ site, Eu+2.18+ is bonded to six Sb3- atoms to form EuSb6 octahedra that share corners with seven EuSb6 octahedra, corners with two equivalent ZnSb4 trigonal pyramids, edges with two equivalent EuSb6 octahedra, edges with four ZnSb4 tetrahedra, a faceface with one EuSb6 octahedra, and a faceface with one ZnSb4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 29–50°. There are a spread of Eu–Sb bond distances ranging from 3.13–3.36 Å. In the third Eu+2.18+ site, Eu+2.18+ is bonded to six Sb3- atoms to form EuSb6 octahedra that share corners with six EuSb6 octahedra, corners with four equivalent ZnSb4 tetrahedra, corners with three equivalent ZnSb4 trigonal pyramids, edges with two equivalent EuSb6 octahedra, edges with two equivalent ZnSb4 tetrahedra, and faces with two EuSb6 octahedra. The corner-sharing octahedra tilt angles range from 29–54°. There are a spread of Eu–Sb bond distances ranging from 3.15–3.46 Å. In the fourth Eu+2.18+ site, Eu+2.18+ is bonded to six Sb3- atoms to form EuSb6 octahedra that share corners with seven EuSb6 octahedra, corners with two equivalent ZnSb4 tetrahedra, corners with two equivalent ZnSb4 trigonal pyramids, edges with four equivalent EuSb6 octahedra, edges with three equivalent ZnSb4 trigonal pyramids, and faces with two EuSb6 octahedra. The corner-sharing octahedra tilt angles range from 34–54°. There are a spread of Eu–Sb bond distances ranging from 3.20–3.51 Å. In the fifth Eu+2.18+ site, Eu+2.18+ is bonded in a 6-coordinate geometry to six Sb3- atoms. There are a spread of Eu–Sb bond distances ranging from 3.22–3.70 Å. In the sixth Eu+2.18+ site, Eu+2.18+ is bonded to six Sb3- atoms to form EuSb6 octahedra that share corners with eight EuSb6 octahedra, corners with four equivalent ZnSb4 tetrahedra, edges with two equivalent EuSb6 octahedra, edges with four equivalent ZnSb4 tetrahedra, and faces with two equivalent EuSb6 octahedra. The corner-sharing octahedra tilt angles range from 34–50°. There are two shorter (3.23 Å) and four longer (3.37 Å) Eu–Sb bond lengths. There are three inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four Sb3- atoms to form distorted ZnSb4 trigonal pyramids that share corners with seven EuSb6 octahedra, corners with two equivalent ZnSb4 tetrahedra, corners with two equivalent ZnSb4 trigonal pyramids, edges with three equivalent EuSb6 octahedra, and a faceface with one EuSb6 octahedra. The corner-sharing octahedra tilt angles range from 25–47°. There are a spread of Zn–Sb bond distances ranging from 2.72–2.97 Å. In the second Zn2+ site, Zn2+ is bonded to four Sb3- atoms to form ZnSb4 tetrahedra that share corners with two equivalent EuSb6 octahedra, corners with four ZnSb4 tetrahedra, corners with two equivalent ZnSb4 trigonal pyramids, and edges with four EuSb6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are a spread of Zn–Sb bond distances ranging from 2.73–2.84 Å. In the third Zn2+ site, Zn2+ is bonded to four Sb3- atoms to form ZnSb4 tetrahedra that share corners with six EuSb6 octahedra, corners with four ZnSb4 tetrahedra, and edges with four EuSb6 octahedra. The corner-sharing octahedra tilt angles range from 44–69°. There are a spread of Zn–Sb bond distances ranging from 2.76–3.13 Å. There are six inequivalent Sb3- sites. In the first Sb3- site, Sb3- is bonded in a 6-coordinate geometry to five Eu+2.18+ and two equivalent Zn2+ atoms. In the second Sb3- site, Sb3- is bonded in a 7-coordinate geometry to five Eu+2.18+ and three Zn2+ atoms. In the third Sb3- site, Sb3- is bonded in a 7-coordinate geometry to six Eu+2.18+ and two equivalent Zn2+ atoms. In the fourth Sb3- site, Sb3- is bonded in a 8-coordinate geometry to six Eu+2.18+ and two Zn2+ atoms. In the fifth Sb3- site, Sb3- is bonded in a 9-coordinate geometry to six Eu+2.18+, two Zn2+, and one Sb3- atom. The Sb–Sb bond length is 2.86 Å. In the sixth Sb3- site, Sb3- is bonded in a 8-coordinate geometry to seven Eu+2.18+ and one Zn2+ atom.

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2020-05-03. Materials Data on Eu11(ZnSb2)6 by Materials Project. https://doi.org/10.17188/1681669

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