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DOE OSTI · 1289129

Materials Data on Nd4O3F7 by Materials Project

Abstract

Nd4O3F7 crystallizes in the monoclinic P2 space group. The structure is three-dimensional. there are two inequivalent Nd sites. In the first Nd site, Nd is bonded in a distorted q6 geometry to three O and six F atoms. There are a spread of Nd–O bond distances ranging from 2.38–2.54 Å. There are a spread of Nd–F bond distances ranging from 2.41–2.56 Å. In the second Nd site, Nd is bonded in a 9-coordinate geometry to three O and six F atoms. There are a spread of Nd–O bond distances ranging from 2.38–2.49 Å. There are a spread of Nd–F bond distances ranging from 2.44–2.67 Å. There are three inequivalent O sites. In the first O site, O is bonded to four Nd atoms to form ONd4 tetrahedra that share corners with eight FNd4 tetrahedra, edges with two equivalent FNd4 tetrahedra, and edges with four ONd4 tetrahedra. In the second O site, O is bonded to four Nd atoms to form ONd4 tetrahedra that share corners with four equivalent ONd4 tetrahedra, corners with four equivalent FNd4 tetrahedra, edges with two equivalent ONd4 tetrahedra, and edges with four FNd4 tetrahedra. In the third O site, O is bonded to four Nd atoms to form ONd4 tetrahedra that share corners with four equivalent ONd4 tetrahedra, corners with eight FNd4 tetrahedra, edges with two equivalent ONd4 tetrahedra, and edges with two equivalent FNd4 tetrahedra. There are five inequivalent F sites. In the first F site, F is bonded to four Nd atoms to form FNd4 tetrahedra that share corners with four equivalent FNd4 tetrahedra, corners with eight ONd4 tetrahedra, edges with two equivalent ONd4 tetrahedra, and edges with two equivalent FNd4 tetrahedra. In the second F site, F is bonded in a trigonal non-coplanar geometry to three Nd atoms. In the third F site, F is bonded to four Nd atoms to form FNd4 tetrahedra that share corners with four equivalent FNd4 tetrahedra, corners with eight ONd4 tetrahedra, edges with two equivalent ONd4 tetrahedra, and edges with two equivalent FNd4 tetrahedra. In the fourth F site, F is bonded in a trigonal non-coplanar geometry to three Nd atoms. In the fifth F site, F is bonded to four Nd atoms to form FNd4 tetrahedra that share corners with four equivalent ONd4 tetrahedra, corners with eight FNd4 tetrahedra, and edges with four ONd4 tetrahedra.

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2020-07-22. Materials Data on Nd4O3F7 by Materials Project. https://doi.org/10.17188/1289129

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