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DOE OSTI · 1744403

Materials Data on Y4Mg25 by Materials Project

Abstract

Mg25Y4 is alpha-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are seven inequivalent Mg sites. In the first Mg site, Mg is bonded in a 4-coordinate geometry to nine Mg and one Y atom. There are three shorter (3.20 Å) and six longer (3.43 Å) Mg–Mg bond lengths. The Mg–Y bond length is 3.58 Å. In the second Mg site, Mg is bonded to eleven Mg and one Y atom to form a mixture of distorted edge and corner-sharing MgYMg11 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 2.97–3.39 Å. The Mg–Y bond length is 3.20 Å. In the third Mg site, Mg is bonded in a 1-coordinate geometry to twelve Mg and one Y atom. There are a spread of Mg–Mg bond distances ranging from 3.00–3.39 Å. The Mg–Y bond length is 3.68 Å. In the fourth Mg site, Mg is bonded in a 2-coordinate geometry to eleven Mg and two equivalent Y atoms. There are a spread of Mg–Mg bond distances ranging from 2.97–3.39 Å. There are one shorter (3.22 Å) and one longer (3.68 Å) Mg–Y bond lengths. In the fifth Mg site, Mg is bonded in a 12-coordinate geometry to eight Mg and four Y atoms. There are one shorter (2.86 Å) and two longer (3.02 Å) Mg–Mg bond lengths. There are a spread of Mg–Y bond distances ranging from 3.46–3.57 Å. In the sixth Mg site, Mg is bonded in a 11-coordinate geometry to eight Mg and three Y atoms. Both Mg–Mg bond lengths are 3.04 Å. There are two shorter (3.46 Å) and one longer (3.47 Å) Mg–Y bond lengths. In the seventh Mg site, Mg is bonded in a 12-coordinate geometry to nine Mg and three Y atoms. There are one shorter (2.87 Å) and one longer (3.02 Å) Mg–Mg bond lengths. There are two shorter (3.45 Å) and one longer (3.57 Å) Mg–Y bond lengths. There are two inequivalent Y sites. In the first Y site, Y is bonded in a 12-coordinate geometry to thirteen Mg and three equivalent Y atoms. All Y–Y bond lengths are 3.64 Å. In the second Y site, Y is bonded in a 3-coordinate geometry to fifteen Mg and one Y atom.

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2020-05-01. Materials Data on Y4Mg25 by Materials Project. https://doi.org/10.17188/1744403

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