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DOE OSTI · 1197102

Materials Data on TiFeSi2 by Materials Project

Abstract

TiFeSi2 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are two inequivalent Ti sites. In the first Ti site, Ti is bonded in a 7-coordinate geometry to six Fe and seven Si atoms. There are a spread of Ti–Fe bond distances ranging from 2.87–3.00 Å. There are a spread of Ti–Si bond distances ranging from 2.58–2.73 Å. In the second Ti site, Ti is bonded in a 8-coordinate geometry to four Fe and eight Si atoms. There are a spread of Ti–Fe bond distances ranging from 2.83–2.92 Å. There are a spread of Ti–Si bond distances ranging from 2.55–2.81 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded in a 12-coordinate geometry to five Ti, one Fe, and six Si atoms. The Fe–Fe bond length is 2.57 Å. There are a spread of Fe–Si bond distances ranging from 2.26–2.45 Å. In the second Fe site, Fe is bonded to four Ti, two equivalent Fe, and six Si atoms to form a mixture of distorted face and edge-sharing FeTi4Fe2Si6 cuboctahedra. There are a spread of Fe–Si bond distances ranging from 2.34–2.39 Å. There are five inequivalent Si sites. In the first Si site, Si is bonded in a 6-coordinate geometry to two equivalent Ti and four Fe atoms. In the second Si site, Si is bonded in a 7-coordinate geometry to three Ti, three Fe, and one Si atom. The Si–Si bond length is 2.36 Å. In the third Si site, Si is bonded in a 2-coordinate geometry to four equivalent Ti, two equivalent Fe, and one Si atom. The Si–Si bond length is 2.42 Å. In the fourth Si site, Si is bonded in a 9-coordinate geometry to six Ti, two equivalent Fe, and one Si atom. The Si–Si bond length is 2.38 Å. In the fifth Si site, Si is bonded in a 9-coordinate geometry to five Ti and four Fe atoms.

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2020-07-15. Materials Data on TiFeSi2 by Materials Project. https://doi.org/10.17188/1197102

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36 MATERIALS SCIENCE↗