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DOE OSTI · 1689592

Materials Data on HoTiFe11N by Materials Project

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Abstract

HoTiFe11N crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. Ho is bonded in a linear geometry to one Ti, ten Fe, and two equivalent N atoms. The Ho–Ti bond length is 3.17 Å. There are a spread of Ho–Fe bond distances ranging from 3.08–3.30 Å. Both Ho–N bond lengths are 2.40 Å. Ti is bonded in a 1-coordinate geometry to one Ho and thirteen Fe atoms. There are a spread of Ti–Fe bond distances ranging from 2.37–2.92 Å. There are six inequivalent Fe sites. In the first Fe site, Fe is bonded to two equivalent Ho, one Ti, and nine Fe atoms to form distorted FeHo2TiFe9 cuboctahedra that share corners with ten equivalent FeHo2TiFe9 cuboctahedra, corners with two equivalent NHo2Fe4 octahedra, edges with four equivalent FeHo2TiFe9 cuboctahedra, faces with six equivalent FeHo2TiFe9 cuboctahedra, and faces with two equivalent NHo2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 67–69°. There are a spread of Fe–Fe bond distances ranging from 2.39–2.63 Å. In the second Fe site, Fe is bonded in a single-bond geometry to six Fe and one N atom. Both Fe–Fe bond lengths are 2.63 Å. The Fe–N bond length is 1.92 Å. In the third Fe site, Fe is bonded in a single-bond geometry to two equivalent Ti, six Fe, and one N atom. Both Fe–Fe bond lengths are 2.66 Å. The Fe–N bond length is 1.91 Å. In the fourth Fe site, Fe is bonded in a single-bond geometry to one Ti, six Fe, and one N atom. Both Fe–Fe bond lengths are 2.67 Å. The Fe–N bond length is 1.91 Å. In the fifth Fe site, Fe is bonded in a 1-coordinate geometry to one Ti and eight Fe atoms. All Fe–Fe bond lengths are 2.95 Å. In the sixth Fe site, Fe is bonded in a 12-coordinate geometry to one Ho, two equivalent Ti, and eleven Fe atoms. The Fe–Fe bond length is 2.43 Å. N is bonded to two equivalent Ho and four Fe atoms to form NHo2Fe4 octahedra that share corners with eight equivalent FeHo2TiFe9 cuboctahedra, corners with two equivalent NHo2Fe4 octahedra, and faces with eight equivalent FeHo2TiFe9 cuboctahedra. The corner-sharing octahedral tilt angles are 2°.

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36 MATERIALS SCIENCEcrystal structureFe-Ho-N-TiHoTiFe11N

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2020-06-04. Materials Data on HoTiFe11N by Materials Project. https://doi.org/10.17188/1689592

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