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DOE OSTI · 1717179

Materials Data on Ta11Al4 by Materials Project

Abstract

Ta11Al4 is beta Uranium-derived structured and crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. there are nine inequivalent Ta sites. In the first Ta site, Ta is bonded in a 6-coordinate geometry to ten Ta and four Al atoms. There are a spread of Ta–Ta bond distances ranging from 2.61–3.30 Å. There are a spread of Ta–Al bond distances ranging from 2.89–2.93 Å. In the second Ta site, Ta is bonded in a 6-coordinate geometry to ten Ta and four Al atoms. There are a spread of Ta–Ta bond distances ranging from 2.57–3.37 Å. There are a spread of Ta–Al bond distances ranging from 2.89–2.94 Å. In the third Ta site, Ta is bonded in a 9-coordinate geometry to nine Ta and six Al atoms. There are two shorter (2.78 Å) and one longer (2.92 Å) Ta–Ta bond lengths. There are a spread of Ta–Al bond distances ranging from 2.99–3.09 Å. In the fourth Ta site, Ta is bonded in a 7-coordinate geometry to eleven Ta and four Al atoms. There are a spread of Ta–Ta bond distances ranging from 2.77–3.06 Å. There are two shorter (2.99 Å) and two longer (3.10 Å) Ta–Al bond lengths. In the fifth Ta site, Ta is bonded in a 6-coordinate geometry to twelve Ta and two equivalent Al atoms. There are a spread of Ta–Ta bond distances ranging from 2.73–3.24 Å. Both Ta–Al bond lengths are 2.85 Å. In the sixth Ta site, Ta is bonded in a 6-coordinate geometry to six Ta and four Al atoms. The Ta–Ta bond length is 2.64 Å. There are a spread of Ta–Al bond distances ranging from 2.80–2.85 Å. In the seventh Ta site, Ta is bonded in a 6-coordinate geometry to six Ta and four Al atoms. The Ta–Ta bond length is 2.68 Å. There are a spread of Ta–Al bond distances ranging from 2.80–2.84 Å. In the eighth Ta site, Ta is bonded in a 6-coordinate geometry to twelve Ta and two equivalent Al atoms. There are one shorter (2.69 Å) and two longer (2.86 Å) Ta–Ta bond lengths. There are one shorter (2.84 Å) and one longer (2.86 Å) Ta–Al bond lengths. In the ninth Ta site, Ta is bonded to ten Ta and two Al atoms to form distorted TaTa10Al2 cuboctahedra that share a cornercorner with one TaTa10Al2 cuboctahedra, corners with ten AlTa10Al2 cuboctahedra, edges with three equivalent TaTa10Al2 cuboctahedra, and faces with seven AlTa11Al cuboctahedra. There are one shorter (2.67 Å) and one longer (2.76 Å) Ta–Al bond lengths. There are five inequivalent Al sites. In the first Al site, Al is bonded to ten Ta and two Al atoms to form AlTa10Al2 cuboctahedra that share corners with four equivalent TaTa10Al2 cuboctahedra, corners with seven AlTa10Al2 cuboctahedra, edges with three equivalent AlTa10Al2 cuboctahedra, and faces with seven AlTa11Al cuboctahedra. There are one shorter (2.71 Å) and one longer (2.79 Å) Al–Al bond lengths. In the second Al site, Al is bonded to eleven Ta and one Al atom to form AlTa11Al cuboctahedra that share corners with two equivalent TaTa10Al2 cuboctahedra, corners with nine AlTa11Al cuboctahedra, edges with three equivalent AlTa11Al cuboctahedra, faces with two equivalent TaTa10Al2 cuboctahedra, and faces with five AlTa10Al2 cuboctahedra. The Al–Al bond length is 2.75 Å. In the third Al site, Al is bonded to ten Ta and two Al atoms to form AlTa10Al2 cuboctahedra that share corners with eleven AlTa10Al2 cuboctahedra, edges with three equivalent AlTa10Al2 cuboctahedra, faces with three AlTa10Al2 cuboctahedra, and faces with four equivalent TaTa10Al2 cuboctahedra. The Al–Al bond length is 2.71 Å. In the fourth Al site, Al is bonded to ten Ta and two equivalent Al atoms to form AlTa10Al2 cuboctahedra that share corners with four equivalent TaTa10Al2 cuboctahedra, corners with twelve AlTa10Al2 cuboctahedra, edges with two equivalent AlTa10Al2 cuboctahedra, faces with two equivalent TaTa10Al2 cuboctahedra, and faces with two equivalent AlTa11Al cuboctahedra. In the fifth Al site, Al is bonded to eight Ta and four Al atoms to form AlTa8Al4 cuboctahedra that share corners with four equivalent TaTa10Al2 cuboctahedra, corners with twelve AlTa10Al2 cuboctahedra, edges with two equivalent AlTa8Al4 cuboctahedra, and faces with four AlTa10Al2 cuboctahedra.

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2020-05-01. Materials Data on Ta11Al4 by Materials Project. https://doi.org/10.17188/1717179

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