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DOE OSTI · 1283849

Materials Data on Eu8C4I9N7 by Materials Project

Abstract

Eu8C4N7I9 crystallizes in the trigonal P3m1 space group. The structure is three-dimensional. there are four inequivalent Eu+2.75+ sites. In the first Eu+2.75+ site, Eu+2.75+ is bonded in a 5-coordinate geometry to three N3- and five I1- atoms. There are one shorter (2.62 Å) and two longer (2.65 Å) Eu–N bond lengths. There are a spread of Eu–I bond distances ranging from 3.30–3.77 Å. In the second Eu+2.75+ site, Eu+2.75+ is bonded in a 7-coordinate geometry to two equivalent N3- and five I1- atoms. Both Eu–N bond lengths are 2.61 Å. There are a spread of Eu–I bond distances ranging from 3.31–3.39 Å. In the third Eu+2.75+ site, Eu+2.75+ is bonded in a 3-coordinate geometry to three equivalent N3- and three equivalent I1- atoms. All Eu–N bond lengths are 2.53 Å. All Eu–I bond lengths are 3.56 Å. In the fourth Eu+2.75+ site, Eu+2.75+ is bonded in a 6-coordinate geometry to three equivalent N3- and three equivalent I1- atoms. All Eu–N bond lengths are 2.62 Å. All Eu–I bond lengths are 3.36 Å. There are two inequivalent C2+ sites. In the first C2+ site, C2+ is bonded in a single-bond geometry to one N3- atom. The C–N bond length is 1.19 Å. In the second C2+ site, C2+ is bonded in a linear geometry to two N3- atoms. Both C–N bond lengths are 1.24 Å. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded to three Eu+2.75+ and one C2+ atom to form a mixture of distorted corner and edge-sharing NEu3C tetrahedra. In the second N3- site, N3- is bonded to three equivalent Eu+2.75+ and one C2+ atom to form distorted edge-sharing NEu3C tetrahedra. In the third N3- site, N3- is bonded to three Eu+2.75+ and one C2+ atom to form a mixture of distorted corner and edge-sharing NEu3C tetrahedra. There are three inequivalent I1- sites. In the first I1- site, I1- is bonded in a 4-coordinate geometry to four Eu+2.75+ atoms. In the second I1- site, I1- is bonded in a 3-coordinate geometry to five Eu+2.75+ atoms. In the third I1- site, I1- is bonded in a 3-coordinate geometry to three Eu+2.75+ atoms.

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2020-07-22. Materials Data on Eu8C4I9N7 by Materials Project. https://doi.org/10.17188/1283849

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