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DOE OSTI · 1288999

Materials Data on Eu4O3F7 by Materials Project

Abstract

Eu4O3F7 crystallizes in the monoclinic P2 space group. The structure is three-dimensional. there are two inequivalent Eu sites. In the first Eu site, Eu is bonded in a distorted q6 geometry to three O and six F atoms. There are a spread of Eu–O bond distances ranging from 2.35–2.55 Å. There are a spread of Eu–F bond distances ranging from 2.41–2.54 Å. In the second Eu site, Eu is bonded in a 9-coordinate geometry to three O and six F atoms. There are a spread of Eu–O bond distances ranging from 2.37–2.50 Å. There are a spread of Eu–F bond distances ranging from 2.41–2.64 Å. There are three inequivalent O sites. In the first O site, O is bonded to four Eu atoms to form OEu4 tetrahedra that share corners with eight FEu4 tetrahedra, edges with two equivalent FEu4 tetrahedra, and edges with four OEu4 tetrahedra. In the second O site, O is bonded to four Eu atoms to form OEu4 tetrahedra that share corners with four equivalent OEu4 tetrahedra, corners with four equivalent FEu4 tetrahedra, edges with two equivalent OEu4 tetrahedra, and edges with four FEu4 tetrahedra. In the third O site, O is bonded to four Eu atoms to form OEu4 tetrahedra that share corners with four equivalent OEu4 tetrahedra, corners with eight FEu4 tetrahedra, edges with two equivalent OEu4 tetrahedra, and edges with two equivalent FEu4 tetrahedra. There are five inequivalent F sites. In the first F site, F is bonded to four Eu atoms to form FEu4 tetrahedra that share corners with four equivalent FEu4 tetrahedra, corners with eight OEu4 tetrahedra, edges with two equivalent OEu4 tetrahedra, and edges with two equivalent FEu4 tetrahedra. In the second F site, F is bonded to four Eu atoms to form FEu4 tetrahedra that share corners with four equivalent FEu4 tetrahedra, corners with eight OEu4 tetrahedra, edges with two equivalent OEu4 tetrahedra, and edges with two equivalent FEu4 tetrahedra. In the third F site, F is bonded in a trigonal non-coplanar geometry to three Eu atoms. In the fourth F site, F is bonded in a trigonal non-coplanar geometry to three Eu atoms. In the fifth F site, F is bonded to four Eu atoms to form FEu4 tetrahedra that share corners with four equivalent OEu4 tetrahedra, corners with eight FEu4 tetrahedra, and edges with four OEu4 tetrahedra.

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BibTeXRIS

2020-07-20. Materials Data on Eu4O3F7 by Materials Project. https://doi.org/10.17188/1288999

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