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DOE OSTI · 1733480

Materials Data on Ta24Al19 by Materials Project

Abstract

Ta24Al19 is Frank-Kasper $\mu$ Phase-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are twelve inequivalent Ta sites. In the first Ta site, Ta is bonded in a 6-coordinate geometry to nine Ta and five Al atoms. There are a spread of Ta–Ta bond distances ranging from 2.64–3.43 Å. There are a spread of Ta–Al bond distances ranging from 2.80–2.93 Å. In the second Ta site, Ta is bonded in a 10-coordinate geometry to seven Ta and seven Al atoms. There are a spread of Ta–Ta bond distances ranging from 2.79–3.30 Å. There are a spread of Ta–Al bond distances ranging from 2.79–3.07 Å. In the third Ta site, Ta is bonded in a 7-coordinate geometry to nine Ta and five Al atoms. There are a spread of Ta–Ta bond distances ranging from 2.65–3.21 Å. There are a spread of Ta–Al bond distances ranging from 2.80–2.92 Å. In the fourth Ta site, Ta is bonded in a 6-coordinate geometry to nine Ta and five Al atoms. There are a spread of Ta–Ta bond distances ranging from 2.87–3.27 Å. There are a spread of Ta–Al bond distances ranging from 2.84–2.89 Å. In the fifth Ta site, Ta is bonded in a 1-coordinate geometry to three Ta and nine Al atoms. There are a spread of Ta–Ta bond distances ranging from 2.82–3.11 Å. There are a spread of Ta–Al bond distances ranging from 2.70–3.20 Å. In the sixth Ta site, Ta is bonded in a 1-coordinate geometry to five Ta and seven Al atoms. There are one shorter (2.73 Å) and one longer (3.33 Å) Ta–Ta bond lengths. There are a spread of Ta–Al bond distances ranging from 2.65–3.05 Å. In the seventh Ta site, Ta is bonded in a 1-coordinate geometry to four Ta and seven Al atoms. There are a spread of Ta–Ta bond distances ranging from 2.83–3.04 Å. There are a spread of Ta–Al bond distances ranging from 2.68–3.09 Å. In the eighth Ta site, Ta is bonded in a 7-coordinate geometry to six Ta and five Al atoms. There are one shorter (2.67 Å) and one longer (3.12 Å) Ta–Ta bond lengths. There are a spread of Ta–Al bond distances ranging from 2.70–2.86 Å. In the ninth Ta site, Ta is bonded in a 7-coordinate geometry to six Ta and five Al atoms. The Ta–Ta bond length is 3.23 Å. There are a spread of Ta–Al bond distances ranging from 2.72–2.93 Å. In the tenth Ta site, Ta is bonded in a 2-coordinate geometry to nine Ta and five Al atoms. There are one shorter (3.25 Å) and one longer (3.37 Å) Ta–Ta bond lengths. There are a spread of Ta–Al bond distances ranging from 2.73–2.93 Å. In the eleventh Ta site, Ta is bonded in a 1-coordinate geometry to six Ta and nine Al atoms. There are a spread of Ta–Al bond distances ranging from 2.78–3.20 Å. In the twelfth Ta site, Ta is bonded in a 1-coordinate geometry to six Ta and eight Al atoms. There are a spread of Ta–Al bond distances ranging from 2.77–3.14 Å. There are ten inequivalent Al sites. In the first Al site, Al is bonded in a 11-coordinate geometry to eight Ta and three Al atoms. There are a spread of Al–Al bond distances ranging from 2.50–3.00 Å. In the second Al site, Al is bonded to seven Ta and five Al atoms to form AlTa7Al5 cuboctahedra that share corners with eight AlTa12 cuboctahedra, an edgeedge with one AlTa7Al5 cuboctahedra, and faces with eight AlTa7Al5 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.65–2.75 Å. In the third Al site, Al is bonded to eight Ta and four Al atoms to form AlTa8Al4 cuboctahedra that share corners with ten AlTa12 cuboctahedra, edges with two equivalent AlTa7Al5 cuboctahedra, and faces with seven AlTa7Al5 cuboctahedra. There are one shorter (2.64 Å) and two longer (2.66 Å) Al–Al bond lengths. In the fourth Al site, Al is bonded in a 12-coordinate geometry to eight Ta and four Al atoms. There are one shorter (2.75 Å) and one longer (2.85 Å) Al–Al bond lengths. In the fifth Al site, Al is bonded to twelve Ta atoms to form AlTa12 cuboctahedra that share corners with sixteen AlTa9Al3 cuboctahedra and faces with six AlTa7Al5 cuboctahedra. In the sixth Al site, Al is bonded to seven Ta and five Al atoms to form distorted AlTa7Al5 cuboctahedra that share corners with eight AlTa7Al5 cuboctahedra, edges with two AlTa9Al3 cuboctahedra, and faces with seven AlTa12 cuboctahedra. There are one shorter (2.61 Å) and one longer (2.79 Å) Al–Al bond lengths. In the seventh Al site, Al is bonded to nine Ta and three Al atoms to form AlTa9Al3 cuboctahedra that share corners with seven AlTa7Al5 cuboctahedra, edges with three AlTa7Al5 cuboctahedra, and faces with six AlTa12 cuboctahedra. There are one shorter (2.56 Å) and one longer (2.61 Å) Al–Al bond lengths. In the eighth Al site, Al is bonded to seven Ta and five Al atoms to form AlTa7Al5 cuboctahedra that share corners with nine AlTa12 cuboctahedra, edges with two equivalent AlTa8Al4 cuboctahedra, and faces with six AlTa7Al5 cuboctahedra. The Al–Al bond length is 2.60 Å. In the ninth Al site, Al is bonded in a 11-coordinate geometry to eight Ta and three Al atoms. In the tenth Al site, Al is bonded to nine Ta and three Al atoms to form distorted AlTa9Al3 cuboctahedra that share corners with eight AlTa12 cuboctahedra, edges with three AlTa7Al5 cuboctahedra, and faces with seven AlTa12 cuboctahedra.

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2020-04-29. Materials Data on Ta24Al19 by Materials Project. https://doi.org/10.17188/1733480

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