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DOE OSTI · 1738424

Materials Data on LaFe8Si5 by Materials Project

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Abstract

LaFe8Si5 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. La3+ is bonded in a 8-coordinate geometry to eight equivalent Si4- atoms. All La–Si bond lengths are 3.22 Å. There are two inequivalent Fe+2.12+ sites. In the first Fe+2.12+ site, Fe+2.12+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are a spread of Fe–Si bond distances ranging from 2.35–2.46 Å. In the second Fe+2.12+ site, Fe+2.12+ is bonded in a 9-coordinate geometry to two equivalent Fe+2.12+ and five Si4- atoms. Both Fe–Fe bond lengths are 2.36 Å. There are a spread of Fe–Si bond distances ranging from 2.40–2.58 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 11-coordinate geometry to two equivalent La3+, eight Fe+2.12+, and one Si4- atom. The Si–Si bond length is 2.52 Å. In the second Si4- site, Si4- is bonded in a cuboctahedral geometry to eight Fe+2.12+ and four equivalent Si4- atoms.

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36 MATERIALS SCIENCEcrystal structureFe-La-SiLaFe8Si5

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2020-05-03. Materials Data on LaFe8Si5 by Materials Project. https://doi.org/10.17188/1738424

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