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DOE OSTI · 1719236

Materials Data on Eu11(ZnAs2)6 by Materials Project

Abstract

Eu11(ZnAs2)6 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 six As3- atoms. There are a spread of Eu–As bond distances ranging from 3.09–3.18 Å. In the second Eu+2.18+ site, Eu+2.18+ is bonded to six As3- atoms to form EuAs6 octahedra that share corners with seven EuAs6 octahedra, corners with two equivalent ZnAs4 trigonal pyramids, edges with two equivalent EuAs6 octahedra, edges with two equivalent ZnAs4 tetrahedra, a faceface with one EuAs6 octahedra, and a faceface with one ZnAs4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 28–54°. There are a spread of Eu–As bond distances ranging from 2.98–3.16 Å. In the third Eu+2.18+ site, Eu+2.18+ is bonded to six As3- atoms to form EuAs6 octahedra that share corners with six EuAs6 octahedra, corners with three equivalent ZnAs4 trigonal pyramids, edges with two equivalent EuAs6 octahedra, edges with two equivalent ZnAs4 tetrahedra, and faces with two EuAs6 octahedra. The corner-sharing octahedra tilt angles range from 28–58°. There are a spread of Eu–As bond distances ranging from 3.01–3.26 Å. In the fourth Eu+2.18+ site, Eu+2.18+ is bonded to six As3- atoms to form EuAs6 octahedra that share corners with seven EuAs6 octahedra, corners with two equivalent ZnAs4 trigonal pyramids, edges with four equivalent EuAs6 octahedra, edges with three equivalent ZnAs4 trigonal pyramids, and faces with two EuAs6 octahedra. The corner-sharing octahedra tilt angles range from 35–58°. There are a spread of Eu–As bond distances ranging from 3.07–3.27 Å. In the fifth Eu+2.18+ site, Eu+2.18+ is bonded in a 5-coordinate geometry to six As3- atoms. There are a spread of Eu–As bond distances ranging from 3.00–3.52 Å. In the sixth Eu+2.18+ site, Eu+2.18+ is bonded to six As3- atoms to form EuAs6 octahedra that share corners with eight EuAs6 octahedra, corners with four equivalent ZnAs4 tetrahedra, edges with two equivalent EuAs6 octahedra, and faces with two equivalent EuAs6 octahedra. The corner-sharing octahedra tilt angles range from 35–54°. There are two shorter (3.10 Å) and four longer (3.12 Å) Eu–As bond lengths. There are three inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four As3- atoms to form distorted ZnAs4 trigonal pyramids that share corners with seven EuAs6 octahedra, corners with two equivalent ZnAs4 tetrahedra, corners with two equivalent ZnAs4 trigonal pyramids, edges with three equivalent EuAs6 octahedra, and a faceface with one EuAs6 octahedra. The corner-sharing octahedra tilt angles range from 27–45°. There are a spread of Zn–As bond distances ranging from 2.51–2.96 Å. In the second Zn2+ site, Zn2+ is bonded to four As3- atoms to form ZnAs4 tetrahedra that share corners with two equivalent EuAs6 octahedra, corners with two equivalent ZnAs4 tetrahedra, corners with two equivalent ZnAs4 trigonal pyramids, and edges with four EuAs6 octahedra. The corner-sharing octahedral tilt angles are 44°. There are a spread of Zn–As bond distances ranging from 2.52–2.76 Å. In the third Zn2+ site, Zn2+ is bonded in a trigonal planar geometry to three As3- atoms. There are two shorter (2.45 Å) and one longer (2.65 Å) Zn–As bond lengths. There are six inequivalent As3- sites. In the first As3- site, As3- is bonded in a 6-coordinate geometry to four Eu+2.18+ and two equivalent Zn2+ atoms. In the second As3- site, As3- is bonded in a 7-coordinate geometry to four Eu+2.18+ and three Zn2+ atoms. In the third As3- site, As3- is bonded in a 2-coordinate geometry to six Eu+2.18+ and two equivalent Zn2+ atoms. In the fourth As3- site, As3- is bonded in a 8-coordinate geometry to six Eu+2.18+ and two Zn2+ atoms. In the fifth As3- site, As3- is bonded in a 8-coordinate geometry to six Eu+2.18+, one Zn2+, and one As3- atom. The As–As bond length is 2.49 Å. In the sixth As3- site, As3- is bonded in a 1-coordinate geometry to seven Eu+2.18+ and one Zn2+ atom.

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2020-05-05. Materials Data on Eu11(ZnAs2)6 by Materials Project. https://doi.org/10.17188/1719236

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