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DOE OSTI · 1758222

Materials Data on Nd2Fe17C by Materials Project

Abstract

Nd2Fe17C crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Nd is bonded in a distorted single-bond geometry to fourteen Fe and one C atom. There are a spread of Nd–Fe bond distances ranging from 3.06–3.35 Å. The Nd–C bond length is 2.58 Å. There are seven inequivalent Fe sites. In the first Fe site, Fe is bonded in a 2-coordinate geometry to one Nd and thirteen Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.40–2.76 Å. In the second Fe site, Fe is bonded in a single-bond geometry to seven Fe and one C atom. There are two shorter (2.48 Å) and four longer (2.57 Å) Fe–Fe bond lengths. The Fe–C bond length is 1.92 Å. In the third Fe site, Fe is bonded to three equivalent Nd and nine Fe atoms to form FeNd3Fe9 cuboctahedra that share corners with seventeen FeNd3Fe9 cuboctahedra, corners with two equivalent CNd2Fe4 octahedra, edges with seven FeNd3Fe9 cuboctahedra, faces with fourteen FeNd3Fe9 cuboctahedra, and a faceface with one CNd2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 65–70°. There are a spread of Fe–Fe bond distances ranging from 2.48–2.69 Å. In the fourth Fe site, Fe is bonded in a single-bond geometry to eight Fe and one C atom. There are two shorter (2.44 Å) and two longer (2.48 Å) Fe–Fe bond lengths. The Fe–C bond length is 1.85 Å. In the fifth Fe site, Fe is bonded to two equivalent Nd and ten Fe atoms to form distorted FeNd2Fe10 cuboctahedra that share corners with sixteen FeNd3Fe9 cuboctahedra, corners with two equivalent CNd2Fe4 octahedra, edges with four FeNd3Fe9 cuboctahedra, an edgeedge with one CNd2Fe4 octahedra, and faces with fifteen FeNd3Fe9 cuboctahedra. The corner-sharing octahedra tilt angles range from 24–30°. There are two shorter (2.44 Å) and one longer (2.48 Å) Fe–Fe bond lengths. In the sixth Fe site, Fe is bonded to two equivalent Nd and ten Fe atoms to form FeNd2Fe10 cuboctahedra that share corners with twelve FeNd3Fe9 cuboctahedra, corners with two equivalent CNd2Fe4 octahedra, edges with eight FeNd2Fe10 cuboctahedra, and faces with twelve FeNd3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles are 45°. In the seventh Fe site, Fe is bonded to two equivalent Nd and ten Fe atoms to form distorted FeNd2Fe10 cuboctahedra that share corners with eighteen FeNd3Fe9 cuboctahedra, edges with six FeNd2Fe10 cuboctahedra, faces with fourteen FeNd3Fe9 cuboctahedra, and faces with two equivalent CNd2Fe4 octahedra. C is bonded to two equivalent Nd and four Fe atoms to form CNd2Fe4 octahedra that share corners with eighteen FeNd2Fe10 cuboctahedra, edges with four equivalent FeNd2Fe10 cuboctahedra, and faces with eight FeNd2Fe10 cuboctahedra.

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2020-09-03. Materials Data on Nd2Fe17C by Materials Project. https://doi.org/10.17188/1758222

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