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DOE OSTI · 1275878

Materials Data on La5Si5I3 by Materials Project

Abstract

La5Si5I3 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are five inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to five Si+2.40- and three I1- atoms to form a mixture of distorted edge and face-sharing LaSi5I3 hexagonal bipyramids. There are a spread of La–Si bond distances ranging from 3.04–3.13 Å. There are two shorter (3.33 Å) and one longer (3.34 Å) La–I bond lengths. In the second La3+ site, La3+ is bonded in a 9-coordinate geometry to eight Si+2.40- and one I1- atom. There are a spread of La–Si bond distances ranging from 3.12–3.19 Å. The La–I bond length is 3.38 Å. In the third La3+ site, La3+ is bonded in a 8-coordinate geometry to four Si+2.40- and four I1- atoms. There are two shorter (3.10 Å) and two longer (3.11 Å) La–Si bond lengths. There are a spread of La–I bond distances ranging from 3.37–3.68 Å. In the fourth La3+ site, La3+ is bonded in a 10-coordinate geometry to nine Si+2.40- and one I1- atom. There are a spread of La–Si bond distances ranging from 3.16–3.28 Å. The La–I bond length is 3.39 Å. In the fifth La3+ site, La3+ is bonded in a 8-coordinate geometry to four Si+2.40- and four I1- atoms. All La–Si bond lengths are 3.10 Å. There are a spread of La–I bond distances ranging from 3.42–3.56 Å. There are five inequivalent Si+2.40- sites. In the first Si+2.40- site, Si+2.40- is bonded in a 8-coordinate geometry to six La3+ and two Si+2.40- atoms. There are one shorter (2.38 Å) and one longer (2.48 Å) Si–Si bond lengths. In the second Si+2.40- site, Si+2.40- is bonded in a 8-coordinate geometry to six La3+ and two Si+2.40- atoms. The Si–Si bond length is 2.49 Å. In the third Si+2.40- site, Si+2.40- is bonded in a 9-coordinate geometry to six La3+ and three Si+2.40- atoms. There are one shorter (2.46 Å) and two longer (2.48 Å) Si–Si bond lengths. In the fourth Si+2.40- site, Si+2.40- is bonded in a 8-coordinate geometry to six La3+ and two Si+2.40- atoms. The Si–Si bond length is 2.38 Å. In the fifth Si+2.40- site, Si+2.40- is bonded in a 8-coordinate geometry to six La3+ and two Si+2.40- atoms. There are three inequivalent I1- sites. In the first I1- site, I1- is bonded to four La3+ atoms to form distorted corner-sharing ILa4 tetrahedra. In the second I1- site, I1- is bonded in a 4-coordinate geometry to four La3+ atoms. In the third I1- site, I1- is bonded in a 5-coordinate geometry to five La3+ atoms.

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2020-07-22. Materials Data on La5Si5I3 by Materials Project. https://doi.org/10.17188/1275878

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36 MATERIALS SCIENCE↗