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DOE OSTI · 1678638

Materials Data on Eu5As4 by Materials Project

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Abstract

Eu5As4 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. there are two inequivalent Eu+2.40+ sites. In the first Eu+2.40+ site, Eu+2.40+ is bonded to six As3- atoms to form a mixture of distorted edge, face, and corner-sharing EuAs6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 38–43°. There are a spread of Eu–As bond distances ranging from 3.09–3.23 Å. In the second Eu+2.40+ site, Eu+2.40+ is bonded to six As3- atoms to form a mixture of face and corner-sharing EuAs6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of Eu–As bond distances ranging from 3.08–3.18 Å. There are two inequivalent As3- sites. In the first As3- site, As3- is bonded to seven Eu+2.40+ atoms to form a mixture of distorted edge and corner-sharing AsEu7 pentagonal bipyramids. In the second As3- site, As3- is bonded in a 9-coordinate geometry to eight Eu+2.40+ and one As3- atom. The As–As bond length is 2.83 Å.

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36 MATERIALS SCIENCEAs-Eucrystal structureEu5As4

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2019-01-11. Materials Data on Eu5As4 by Materials Project. https://doi.org/10.17188/1678638

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