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DOE OSTI · 1204499

Materials Data on ScFeSi2 by Materials Project

Abstract

ScFeSi2 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. there are three inequivalent Sc sites. In the first Sc site, Sc is bonded in a 12-coordinate geometry to four Fe and eight Si atoms. There are two shorter (2.97 Å) and two longer (3.02 Å) Sc–Fe bond lengths. There are a spread of Sc–Si bond distances ranging from 2.76–2.90 Å. In the second Sc site, Sc is bonded in a 7-coordinate geometry to four Fe and seven Si atoms. There are two shorter (3.00 Å) and two longer (3.01 Å) Sc–Fe bond lengths. There are a spread of Sc–Si bond distances ranging from 2.69–2.83 Å. In the third Sc site, Sc is bonded in a 8-coordinate geometry to four Fe and eight Si atoms. There are two shorter (2.92 Å) and two longer (2.99 Å) Sc–Fe bond lengths. There are a spread of Sc–Si bond distances ranging from 2.75–2.88 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded in a 12-coordinate geometry to four Sc and six Si atoms. There are a spread of Fe–Si bond distances ranging from 2.31–2.49 Å. In the second Fe site, Fe is bonded to four Sc, two equivalent Fe, and six Si atoms to form a mixture of distorted corner, edge, and face-sharing FeSc4Fe2Si6 cuboctahedra. Both Fe–Fe bond lengths are 2.53 Å. There are a spread of Fe–Si bond distances ranging from 2.42–2.47 Å. In the third Fe site, Fe is bonded to four Sc, two equivalent Fe, and six Si atoms to form a mixture of distorted corner, edge, and face-sharing FeSc4Fe2Si6 cuboctahedra. Both Fe–Fe bond lengths are 2.53 Å. There are four shorter (2.42 Å) and two longer (2.48 Å) Fe–Si bond lengths. There are six inequivalent Si sites. In the first Si site, Si is bonded in a 10-coordinate geometry to six Sc, two equivalent Fe, and two equivalent Si atoms. Both Si–Si bond lengths are 2.53 Å. In the second Si site, Si is bonded in a 12-coordinate geometry to four Sc, two equivalent Fe, and two equivalent Si atoms. There are one shorter (2.50 Å) and one longer (2.57 Å) Si–Si bond lengths. In the third Si site, Si is bonded in a 7-coordinate geometry to three Sc and four Fe atoms. In the fourth Si site, Si is bonded in a 7-coordinate geometry to three Sc, three Fe, and one Si atom. The Si–Si bond length is 2.37 Å. In the fifth Si site, Si is bonded in a 12-coordinate geometry to four Sc and four Fe atoms. In the sixth Si site, Si is bonded in a 7-coordinate geometry to three equivalent Sc, three Fe, and one Si atom.

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2020-07-15. Materials Data on ScFeSi2 by Materials Project. https://doi.org/10.17188/1204499

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