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DOE OSTI · 1728318

Materials Data on TiMnAl by Materials Project

Abstract

MnAlTi crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are six inequivalent Ti sites. In the first Ti site, Ti is bonded in a 12-coordinate geometry to four Ti, five Mn, and seven Al atoms. There are a spread of Ti–Ti bond distances ranging from 3.03–3.20 Å. There are a spread of Ti–Mn bond distances ranging from 2.80–2.96 Å. There are a spread of Ti–Al bond distances ranging from 2.88–2.95 Å. In the second Ti site, Ti is bonded in a 1-coordinate geometry to four Ti, seven Mn, and five Al atoms. There are one shorter (2.85 Å) and two longer (3.03 Å) Ti–Ti bond lengths. There are a spread of Ti–Mn bond distances ranging from 2.80–2.98 Å. There are a spread of Ti–Al bond distances ranging from 2.78–2.99 Å. In the third Ti site, Ti is bonded in a 1-coordinate geometry to four Ti, seven Mn, and five Al atoms. There are two shorter (3.03 Å) and one longer (3.05 Å) Ti–Ti bond lengths. There are a spread of Ti–Mn bond distances ranging from 2.80–2.98 Å. There are a spread of Ti–Al bond distances ranging from 2.78–2.99 Å. In the fourth Ti site, Ti is bonded in a 12-coordinate geometry to four Ti, five Mn, and seven Al atoms. There are one shorter (3.05 Å) and one longer (3.20 Å) Ti–Ti bond lengths. There are a spread of Ti–Mn bond distances ranging from 2.80–2.96 Å. There are a spread of Ti–Al bond distances ranging from 2.88–2.95 Å. In the fifth Ti site, Ti is bonded in a 1-coordinate geometry to four Ti, seven Mn, and five Al atoms. The Ti–Ti bond length is 2.85 Å. There are a spread of Ti–Mn bond distances ranging from 2.80–2.98 Å. There are a spread of Ti–Al bond distances ranging from 2.78–2.99 Å. In the sixth Ti site, Ti is bonded in a 1-coordinate geometry to four Ti, seven Mn, and five Al atoms. There are two shorter (3.03 Å) and one longer (3.05 Å) Ti–Ti bond lengths. There are a spread of Ti–Mn bond distances ranging from 2.80–2.98 Å. There are a spread of Ti–Al bond distances ranging from 2.78–2.99 Å. There are three inequivalent Mn sites. In the first Mn site, Mn is bonded to six Ti and six Al atoms to form distorted MnTi6Al6 cuboctahedra that share corners with four equivalent AlTi6Mn4Al2 cuboctahedra, corners with fourteen MnTi6Al6 cuboctahedra, edges with six MnTi6Al6 cuboctahedra, faces with four equivalent MnTi6Mn4Al2 cuboctahedra, and faces with fourteen AlTi6Mn4Al2 cuboctahedra. There are two shorter (2.40 Å) and four longer (2.52 Å) Mn–Al bond lengths. In the second Mn site, Mn is bonded to six Ti, four Mn, and two equivalent Al atoms to form distorted MnTi6Mn4Al2 cuboctahedra that share corners with eight MnTi6Al6 cuboctahedra, corners with ten AlTi6Mn4Al2 cuboctahedra, edges with two equivalent MnTi6Mn4Al2 cuboctahedra, edges with four equivalent AlTi6Mn2Al4 cuboctahedra, faces with eight AlTi6Mn4Al2 cuboctahedra, and faces with ten MnTi6Al6 cuboctahedra. There are a spread of Mn–Mn bond distances ranging from 2.29–2.66 Å. Both Mn–Al bond lengths are 2.47 Å. In the third Mn site, Mn is bonded to six Ti, four equivalent Mn, and two equivalent Al atoms to form distorted MnTi6Mn4Al2 cuboctahedra that share corners with six MnTi6Al6 cuboctahedra, corners with twelve AlTi6Mn4Al2 cuboctahedra, edges with six MnTi6Al6 cuboctahedra, faces with eight equivalent MnTi6Mn4Al2 cuboctahedra, and faces with ten AlTi6Mn4Al2 cuboctahedra. Both Mn–Al bond lengths are 2.49 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to six Ti, four Mn, and two equivalent Al atoms to form distorted AlTi6Mn4Al2 cuboctahedra that share corners with four equivalent AlTi6Mn2Al4 cuboctahedra, corners with eight MnTi6Al6 cuboctahedra, edges with six equivalent AlTi6Mn4Al2 cuboctahedra, faces with eight AlTi6Mn4Al2 cuboctahedra, and faces with twelve MnTi6Al6 cuboctahedra. Both Al–Al bond lengths are 2.60 Å. In the second Al site, Al is bonded to six Ti, two equivalent Mn, and four Al atoms to form distorted AlTi6Mn2Al4 cuboctahedra that share corners with eight AlTi6Mn4Al2 cuboctahedra, corners with ten MnTi6Mn4Al2 cuboctahedra, edges with two equivalent AlTi6Mn2Al4 cuboctahedra, edges with four equivalent MnTi6Mn4Al2 cuboctahedra, faces with eight MnTi6Al6 cuboctahedra, and faces with ten AlTi6Mn4Al2 cuboctahedra. There are one shorter (2.43 Å) and one longer (2.55 Å) Al–Al bond lengths.

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2019-01-12. Materials Data on TiMnAl by Materials Project. https://doi.org/10.17188/1728318

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