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DOE OSTI · 1705990

Materials Data on Eu2Mg3H10 by Materials Project

Abstract

Eu2Mg3H10 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six H1- atoms to form MgH6 octahedra that share corners with four MgH6 octahedra, edges with two equivalent EuH12 cuboctahedra, and edges with two equivalent MgH6 octahedra. The corner-sharing octahedra tilt angles range from 52–60°. There are a spread of Mg–H bond distances ranging from 1.90–1.93 Å. In the second Mg2+ site, Mg2+ is bonded to six H1- atoms to form MgH6 octahedra that share corners with five MgH6 octahedra and faces with three equivalent EuH12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–60°. There are a spread of Mg–H bond distances ranging from 1.90–1.96 Å. In the third Mg2+ site, Mg2+ is bonded to six H1- atoms to form MgH6 octahedra that share corners with two equivalent EuH12 cuboctahedra, corners with three MgH6 octahedra, an edgeedge with one MgH6 octahedra, and faces with two equivalent EuH12 cuboctahedra. The corner-sharing octahedra tilt angles range from 9–52°. There are a spread of Mg–H bond distances ranging from 1.86–2.02 Å. There are two inequivalent Eu2+ sites. In the first Eu2+ site, Eu2+ is bonded to twelve H1- atoms to form distorted EuH12 cuboctahedra that share corners with four equivalent EuH12 cuboctahedra, corners with two equivalent MgH6 octahedra, an edgeedge with one EuH12 cuboctahedra, edges with two equivalent MgH6 octahedra, and faces with five MgH6 octahedra. The corner-sharing octahedral tilt angles are 47°. There are a spread of Eu–H bond distances ranging from 2.52–2.84 Å. In the second Eu2+ site, Eu2+ is bonded in a 12-coordinate geometry to twelve H1- atoms. There are a spread of Eu–H bond distances ranging from 2.42–2.90 Å. There are eight inequivalent H1- sites. In the first H1- site, H1- is bonded in a distorted single-bond geometry to one Mg2+ and four Eu2+ atoms. In the second H1- site, H1- is bonded in a linear geometry to two equivalent Mg2+ and four Eu2+ atoms. In the third H1- site, H1- is bonded to one Mg2+ and three Eu2+ atoms to form a mixture of distorted edge and corner-sharing HEu3Mg tetrahedra. In the fourth H1- site, H1- is bonded in a distorted linear geometry to two Mg2+ and three Eu2+ atoms. In the fifth H1- site, H1- is bonded in a distorted bent 120 degrees geometry to two Mg2+ and two Eu2+ atoms. In the sixth H1- site, H1- is bonded in a 4-coordinate geometry to two equivalent Mg2+ and two equivalent Eu2+ atoms. In the seventh H1- site, H1- is bonded in a trigonal planar geometry to three Mg2+ atoms. In the eighth H1- site, H1- is bonded in a distorted L-shaped geometry to two equivalent Mg2+ and one Eu2+ atom.

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2020-05-03. Materials Data on Eu2Mg3H10 by Materials Project. https://doi.org/10.17188/1705990

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