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DOE OSTI · 1275838

Materials Data on Al17Mo4 by Materials Project

Abstract

Al17Mo4 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are four inequivalent Mo sites. In the first Mo site, Mo is bonded in a 11-coordinate geometry to eleven Al atoms. There are a spread of Mo–Al bond distances ranging from 2.64–2.87 Å. In the second Mo site, Mo is bonded to twelve Al atoms to form MoAl12 cuboctahedra that share corners with five equivalent MoAl12 cuboctahedra, corners with five equivalent AlAl9Mo3 cuboctahedra, edges with four equivalent MoAl12 cuboctahedra, and faces with four equivalent AlAl9Mo3 cuboctahedra. There are a spread of Mo–Al bond distances ranging from 2.70–2.90 Å. In the third Mo site, Mo is bonded to twelve Al atoms to form MoAl12 cuboctahedra that share corners with five equivalent MoAl12 cuboctahedra, corners with five equivalent AlAl9Mo3 cuboctahedra, edges with four equivalent MoAl12 cuboctahedra, and faces with four equivalent AlAl9Mo3 cuboctahedra. There are a spread of Mo–Al bond distances ranging from 2.71–2.91 Å. In the fourth Mo site, Mo is bonded in a 11-coordinate geometry to eleven Al atoms. There are a spread of Mo–Al bond distances ranging from 2.64–2.87 Å. There are eighteen inequivalent Al sites. In the first Al site, Al is bonded in a 11-coordinate geometry to four Mo and seven Al atoms. There are a spread of Al–Al bond distances ranging from 2.59–2.92 Å. In the second Al site, Al is bonded in a distorted bent 150 degrees geometry to two equivalent Mo and four equivalent Al atoms. There are two shorter (2.71 Å) and two longer (2.78 Å) Al–Al bond lengths. In the third Al site, Al is bonded in a 2-coordinate geometry to two Mo and five Al atoms. There are a spread of Al–Al bond distances ranging from 2.67–2.93 Å. In the fourth Al site, Al is bonded in a distorted bent 150 degrees geometry to two equivalent Mo and four Al atoms. There are two shorter (2.71 Å) and two longer (2.79 Å) Al–Al bond lengths. In the fifth Al site, Al is bonded in a distorted bent 150 degrees geometry to two equivalent Mo and four Al atoms. There are a spread of Al–Al bond distances ranging from 2.70–2.80 Å. In the sixth Al site, Al is bonded in a 3-coordinate geometry to three Mo and eight Al atoms. There are a spread of Al–Al bond distances ranging from 2.67–2.87 Å. In the seventh Al site, Al is bonded in a 12-coordinate geometry to three Mo and nine Al atoms. There are a spread of Al–Al bond distances ranging from 2.67–2.88 Å. In the eighth Al site, Al is bonded in a 11-coordinate geometry to four Mo and seven Al atoms. There are a spread of Al–Al bond distances ranging from 2.69–2.93 Å. In the ninth Al site, Al is bonded in a 2-coordinate geometry to two equivalent Mo and four Al atoms. There are one shorter (2.66 Å) and one longer (2.81 Å) Al–Al bond lengths. In the tenth Al site, Al is bonded to three equivalent Mo and nine Al atoms to form distorted AlAl9Mo3 cuboctahedra that share corners with five equivalent MoAl12 cuboctahedra, corners with five equivalent AlAl9Mo3 cuboctahedra, edges with two equivalent AlAl9Mo3 cuboctahedra, faces with three equivalent AlAl9Mo3 cuboctahedra, and faces with four equivalent MoAl12 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.81–2.90 Å. In the eleventh Al site, Al is bonded to three equivalent Mo and nine Al atoms to form distorted AlAl9Mo3 cuboctahedra that share corners with five equivalent MoAl12 cuboctahedra, corners with five equivalent AlAl9Mo3 cuboctahedra, edges with two equivalent AlAl9Mo3 cuboctahedra, faces with three equivalent AlAl9Mo3 cuboctahedra, and faces with four equivalent MoAl12 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.71–2.86 Å. In the twelfth Al site, Al is bonded in a 3-coordinate geometry to three Mo and eight Al atoms. There are a spread of Al–Al bond distances ranging from 2.70–2.80 Å. In the thirteenth Al site, Al is bonded in a 2-coordinate geometry to two Mo and five Al atoms. In the fourteenth Al site, Al is bonded in a 2-coordinate geometry to two equivalent Mo and four Al atoms. There are one shorter (2.67 Å) and one longer (2.83 Å) Al–Al bond lengths. In the fifteenth Al site, Al is bonded in a distorted bent 150 degrees geometry to two equivalent Mo and four equivalent Al atoms. In the sixteenth Al site, Al is bonded in a 3-coordinate geometry to three Mo and six Al atoms. In the seventeenth Al site, Al is bonded in a 3-coordinate geometry to three Mo and six Al atoms. The Al–Al bond length is 2.80 Å. In the eighteenth Al site, Al is bonded in a 12-coordinate geometry to three Mo and nine Al atoms.

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2020-05-02. Materials Data on Al17Mo4 by Materials Project. https://doi.org/10.17188/1275838

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