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DOE OSTI · 1750949

Materials Data on Th2Fe14B by Materials Project

Abstract

Th2Fe14B crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. there are two inequivalent Th sites. In the first Th site, Th is bonded in a 12-coordinate geometry to sixteen Fe and two equivalent B atoms. There are a spread of Th–Fe bond distances ranging from 3.03–3.25 Å. Both Th–B bond lengths are 3.22 Å. In the second Th site, Th is bonded in a 1-coordinate geometry to sixteen Fe and one B atom. There are a spread of Th–Fe bond distances ranging from 3.03–3.35 Å. The Th–B bond length is 2.86 Å. There are six inequivalent Fe sites. In the first Fe site, Fe is bonded in a distorted q6 geometry to two Th and ten Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.38–2.65 Å. In the second Fe site, Fe is bonded to four Th and eight Fe atoms to form FeTh4Fe8 cuboctahedra that share corners with twelve FeTh4Fe8 cuboctahedra and faces with four equivalent FeTh3Fe9 cuboctahedra. All Fe–Fe bond lengths are 2.56 Å. In the third Fe site, Fe is bonded in a distorted L-shaped geometry to two equivalent Th, four Fe, and two equivalent B atoms. There are two shorter (2.51 Å) and two longer (2.75 Å) Fe–Fe bond lengths. Both Fe–B bond lengths are 2.06 Å. In the fourth Fe site, Fe is bonded in a 2-coordinate geometry to two Th and twelve Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.63–2.79 Å. In the fifth Fe site, Fe is bonded in a distorted single-bond geometry to two Th, seven Fe, and one B atom. The Fe–Fe bond length is 2.60 Å. The Fe–B bond length is 2.10 Å. In the sixth Fe site, Fe is bonded to three Th and nine Fe atoms to form distorted FeTh3Fe9 cuboctahedra that share corners with eight FeTh4Fe8 cuboctahedra, an edgeedge with one FeTh3Fe9 cuboctahedra, and faces with four FeTh4Fe8 cuboctahedra. The Fe–Fe bond length is 2.41 Å. B is bonded in a 6-coordinate geometry to three Th and six Fe atoms.

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2020-06-05. Materials Data on Th2Fe14B by Materials Project. https://doi.org/10.17188/1750949

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36 MATERIALS SCIENCE↗