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DOE OSTI · 1274248

Materials Data on Mg41Al67 by Materials Project

Abstract

Mg41Al67 crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded to three Mg and nine Al atoms to form distorted MgMg3Al9 cuboctahedra that share corners with four MgMg3Al9 cuboctahedra, corners with eight AlMg6Al6 cuboctahedra, edges with seven MgMg3Al9 cuboctahedra, edges with fourteen AlMg6Al6 cuboctahedra, faces with six MgMg3Al9 cuboctahedra, and faces with eleven AlMg4Al8 cuboctahedra. There are one shorter (3.04 Å) and two longer (3.08 Å) Mg–Mg bond lengths. There are a spread of Mg–Al bond distances ranging from 2.88–2.99 Å. In the second Mg site, Mg is bonded to eight Mg and four Al atoms to form distorted MgMg8Al4 cuboctahedra that share corners with four equivalent MgMg3Al9 cuboctahedra, corners with eight AlMg6Al6 cuboctahedra, edges with twelve MgMg3Al9 cuboctahedra, edges with twelve AlMg6Al6 cuboctahedra, faces with eight AlMg6Al6 cuboctahedra, and faces with ten MgMg8Al4 cuboctahedra. There are four shorter (3.02 Å) and four longer (3.16 Å) Mg–Mg bond lengths. All Mg–Al bond lengths are 2.97 Å. In the third Mg site, Mg is bonded to six Mg and six Al atoms to form MgMg6Al6 cuboctahedra that share corners with three equivalent MgMg6Al6 cuboctahedra, corners with six equivalent AlMg5Al7 cuboctahedra, edges with nine MgMg3Al9 cuboctahedra, edges with fifteen AlMg6Al6 cuboctahedra, faces with nine MgMg3Al9 cuboctahedra, and faces with nine AlMg6Al6 cuboctahedra. All Mg–Al bond lengths are 3.02 Å. In the fourth Mg site, Mg is bonded to twelve Al atoms to form MgAl12 cuboctahedra that share corners with twelve AlMg6Al6 cuboctahedra, edges with twenty-four MgMg3Al9 cuboctahedra, faces with two equivalent MgMg8Al4 cuboctahedra, and faces with sixteen AlMg6Al6 cuboctahedra. All Mg–Al bond lengths are 2.98 Å. There are fifteen inequivalent Al sites. In the first Al site, Al is bonded to six Mg and six Al atoms to form distorted AlMg6Al6 cuboctahedra that share corners with six MgMg3Al9 cuboctahedra, corners with six AlMg6Al6 cuboctahedra, edges with eight MgMg3Al9 cuboctahedra, edges with fourteen AlMg6Al6 cuboctahedra, faces with nine MgMg3Al9 cuboctahedra, and faces with nine AlMg6Al6 cuboctahedra. There are a spread of Al–Mg bond distances ranging from 2.97–2.99 Å. There are a spread of Al–Al bond distances ranging from 2.89–3.06 Å. In the second Al site, Al is bonded to six Mg and six Al atoms to form distorted AlMg6Al6 cuboctahedra that share corners with six MgMg3Al9 cuboctahedra, corners with six AlMg4Al8 cuboctahedra, edges with eight MgMg3Al9 cuboctahedra, edges with fourteen AlMg6Al6 cuboctahedra, faces with nine MgMg3Al9 cuboctahedra, and faces with nine AlMg6Al6 cuboctahedra. There are two shorter (2.99 Å) and two longer (3.02 Å) Al–Mg bond lengths. There are a spread of Al–Al bond distances ranging from 2.89–3.06 Å. In the third Al site, Al is bonded to four equivalent Mg and eight Al atoms to form distorted AlMg4Al8 cuboctahedra that share corners with five MgMg3Al9 cuboctahedra, corners with seven AlMg6Al6 cuboctahedra, edges with six MgMg3Al9 cuboctahedra, edges with sixteen AlMg6Al6 cuboctahedra, faces with six equivalent MgMg3Al9 cuboctahedra, and faces with ten AlAl12 cuboctahedra. All Al–Mg bond lengths are 2.98 Å. There are a spread of Al–Al bond distances ranging from 2.88–3.08 Å. In the fourth Al site, Al is bonded to four equivalent Mg and eight Al atoms to form distorted AlMg4Al8 cuboctahedra that share corners with five MgMg3Al9 cuboctahedra, corners with seven AlMg6Al6 cuboctahedra, edges with six MgMg3Al9 cuboctahedra, edges with sixteen AlMg6Al6 cuboctahedra, faces with six equivalent MgMg3Al9 cuboctahedra, and faces with ten AlMg4Al8 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.88–3.08 Å. In the fifth Al site, Al is bonded to five Mg and seven Al atoms to form distorted AlMg5Al7 cuboctahedra that share corners with four equivalent MgMg6Al6 cuboctahedra, corners with six AlAl12 cuboctahedra, edges with eight MgMg3Al9 cuboctahedra, edges with sixteen AlMg6Al6 cuboctahedra, faces with seven MgMg3Al9 cuboctahedra, and faces with nine AlMg6Al6 cuboctahedra. There are two shorter (2.94 Å) and two longer (2.97 Å) Al–Al bond lengths. In the sixth Al site, Al is bonded to four equivalent Mg and eight Al atoms to form distorted AlMg4Al8 cuboctahedra that share corners with five MgMg3Al9 cuboctahedra, corners with seven AlMg6Al6 cuboctahedra, edges with six MgMg3Al9 cuboctahedra, edges with sixteen AlMg6Al6 cuboctahedra, faces with six equivalent MgMg3Al9 cuboctahedra, and faces with ten AlMg4Al8 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.88–3.08 Å. In the seventh Al site, Al is bonded to four equivalent Mg and eight Al atoms to form distorted AlMg4Al8 cuboctahedra that share corners with six MgMg3Al9 cuboctahedra, corners with six AlMg6Al6 cuboctahedra, edges with twelve MgMg3Al9 cuboctahedra, edges with twelve AlMg6Al6 cuboctahedra, faces with five MgMg3Al9 cuboctahedra, and faces with eleven AlMg4Al8 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.89–3.05 Å. In the eighth Al site, Al is bonded to six Mg and six Al atoms to form distorted AlMg6Al6 cuboctahedra that share corners with six MgMg3Al9 cuboctahedra, corners with six AlMg6Al6 cuboctahedra, edges with eight MgMg3Al9 cuboctahedra, edges with fourteen AlMg6Al6 cuboctahedra, faces with nine MgMg3Al9 cuboctahedra, and faces with nine AlMg5Al7 cuboctahedra. Both Al–Mg bond lengths are 2.99 Å. There are one shorter (2.98 Å) and two longer (3.06 Å) Al–Al bond lengths. In the ninth Al site, Al is bonded to six Mg and six Al atoms to form distorted AlMg6Al6 cuboctahedra that share corners with six MgMg3Al9 cuboctahedra, corners with six AlMg6Al6 cuboctahedra, edges with eight MgMg3Al9 cuboctahedra, edges with fourteen AlMg6Al6 cuboctahedra, faces with nine MgMg3Al9 cuboctahedra, and faces with nine AlMg6Al6 cuboctahedra. The Al–Al bond length is 3.06 Å. In the tenth Al site, Al is bonded to twelve Al atoms to form AlAl12 cuboctahedra that share corners with twelve equivalent AlMg5Al7 cuboctahedra, edges with twenty-four equivalent MgMg3Al9 cuboctahedra, and faces with twelve AlMg4Al8 cuboctahedra. All Al–Al bond lengths are 2.88 Å. In the eleventh Al site, Al is bonded to six Mg and six Al atoms to form distorted AlMg6Al6 cuboctahedra that share corners with six MgMg3Al9 cuboctahedra, corners with six AlMg6Al6 cuboctahedra, edges with eight MgMg3Al9 cuboctahedra, edges with fourteen AlMg6Al6 cuboctahedra, faces with nine MgMg3Al9 cuboctahedra, and faces with nine AlMg6Al6 cuboctahedra. The Al–Mg bond length is 2.97 Å. There are a spread of Al–Al bond distances ranging from 2.89–3.06 Å. In the twelfth Al site, Al is bonded to four equivalent Mg and eight Al atoms to form distorted AlMg4Al8 cuboctahedra that share corners with five MgMg3Al9 cuboctahedra, corners with seven AlMg6Al6 cuboctahedra, edges with six MgMg3Al9 cuboctahedra, edges with sixteen AlMg4Al8 cuboctahedra, faces with six equivalent MgMg3Al9 cuboctahedra, and faces with ten AlAl12 cuboctahedra. All Al–Mg bond lengths are 2.98 Å. There are a spread of Al–Al bond distances ranging from 2.88–3.08 Å. In the thirteenth Al site, Al is bonded in a distorted rectangular see-saw-like geometry to four equivalent Mg and eight Al atoms. Both Al–Al bond lengths are 2.92 Å. In the fourteenth Al site, Al is bonded to four equivalent Mg and eight Al atoms to form distorted AlMg4Al8 cuboctahedra that share corners with five MgMg3Al9 cuboctahedra, corners with seven AlMg6Al6 cuboctahedra, edges with six MgMg3Al9 cuboctahedra, edges with sixteen AlMg6Al6 cuboctahedra, faces with six equivalent MgMg3Al9 cuboctahedra, and faces with ten AlMg4Al8 cuboctahedra. All Al–Mg bond lengths are 2.98 Å. There are two shorter (2.88 Å) and one longer (3.08 Å) Al–Al bond lengths. In the fifteenth Al site, Al is bonded to four equivalent Mg and eight Al atoms to form distorted AlMg4Al8 cuboctahedra that share corners with five MgMg3Al9 cuboctahedra, corners with seven AlMg6Al6 cuboctahedra, edges with six MgMg3Al9 cuboctahedra, edges with sixteen AlMg6Al6 cuboctahedra, faces with six equivalent MgMg3Al9 cuboctahedra, and faces with ten AlMg4Al8 cuboctahedra. All Al–Mg bond lengths are 2.98 Å. The Al–Al bond length is 3.08 Å.

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2020-04-30. Materials Data on Mg41Al67 by Materials Project. https://doi.org/10.17188/1274248

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