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DOE OSTI · 1299889

Materials Data on La2MgI8 by Materials Project

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Abstract

MgLa2I8 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Mg2+ is bonded to six I1- atoms to form MgI6 octahedra that share corners with two equivalent LaI7 pentagonal bipyramids and edges with four equivalent LaI7 pentagonal bipyramids. There are a spread of Mg–I bond distances ranging from 2.87–3.12 Å. La3+ is bonded to seven I1- atoms to form distorted LaI7 pentagonal bipyramids that share a cornercorner with one MgI6 octahedra, edges with two equivalent MgI6 octahedra, and edges with three equivalent LaI7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 52°. There are a spread of La–I bond distances ranging from 3.17–3.50 Å. There are four inequivalent I1- sites. In the first I1- site, I1- is bonded in a water-like geometry to two equivalent La3+ atoms. In the second I1- site, I1- is bonded in a 3-coordinate geometry to one Mg2+ and two equivalent La3+ atoms. In the third I1- site, I1- is bonded in a water-like geometry to one Mg2+ and one La3+ atom. In the fourth I1- site, I1- is bonded in a distorted trigonal non-coplanar geometry to one Mg2+ and two equivalent La3+ atoms.

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36 MATERIALS SCIENCEcrystal structureI-La-MgLa2MgI8

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2020-04-29. Materials Data on La2MgI8 by Materials Project. https://doi.org/10.17188/1299889

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