DOE OSTI2020
Dy(Mg4Al3)4 is gamma-brass-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are five inequivalent Mg sites. In the first Mg site, Mg is bonded in a 11-coordinate geometry to five Mg and six Al atoms. There are a spread of Mg–Mg bond distances ranging from 3.05–3.36 Å. There are a spread of Mg–Al bond distances ranging from 3.05–3.13 Å. In the second Mg site, Mg is bonded in a 3-coordinate geometry to seven Mg, one Dy, and five Al atoms. There are a spread of Mg–Mg bond distances ranging from 3.16–3.29 Å. The Mg–Dy bond length is 3.59 Å. There are a spread of Mg–Al bond distances ranging from 2.88–3.22 Å. In the third Mg site, Mg is bonded in a 9-coordinate geometry to three equivalent Mg, one Dy, and twelve Al atoms. The Mg–Dy bond length is 3.31 Å. There are a spread of Mg–Al bond distances ranging from 3.14–3.25 Å. In the fourth Mg site, Mg is bonded in a 1-coordinate geometry to seven Mg, one Dy, and five Al atoms. There are two shorter (3.12 Å) and two longer (3.15 Å) Mg–Mg bond lengths. The Mg–Dy bond length is 3.12 Å. There are a spread of Mg–Al bond distances ranging from 2.81–3.15 Å. In the fifth Mg site, Mg is bonded in a 12-coordinate geometry to seven Mg and five Al atoms. Both Mg–Mg bond lengths are 3.04 Å. There are a spread of Mg–Al bond distances ranging from 2.96–3.33 Å. Dy is bonded in a 12-coordinate geometry to seven Mg and nine Al atoms. There are six shorter (3.21 Å) and three longer (3.22 Å) Dy–Al bond lengths. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 12-coordinate geometry to eight Mg, one Dy, and three Al atoms. There are one shorter (2.68 Å) and two longer (2.74 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a 11-coordinate geometry to eight Mg and three Al atoms. Both Al–Al bond lengths are 2.75 Å. In the third Al site, Al is bonded in a distorted q6 geometry to seven Mg, one Dy, and three Al atoms. There are one shorter (2.72 Å) and one longer (2.78 Å) Al–Al bond lengths.