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DOE OSTI · 1719905

Materials Data on Gd8MgAlNi2 by Materials Project

Abstract

MgGd8Ni2Al crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to one Mg, nine Gd, and two Al atoms to form distorted MgGd9MgAl2 cuboctahedra that share a cornercorner with one MgGd9MgAl2 cuboctahedra, corners with two AlGd9Mg2Al cuboctahedra, a faceface with one MgGd9MgAl2 cuboctahedra, and faces with two AlGd9Mg2Al cuboctahedra. The Mg–Mg bond length is 2.99 Å. There are a spread of Mg–Gd bond distances ranging from 3.36–3.60 Å. Both Mg–Al bond lengths are 2.99 Å. In the second Mg site, Mg is bonded to one Mg, nine Gd, and two Al atoms to form distorted MgGd9MgAl2 cuboctahedra that share a cornercorner with one MgGd9MgAl2 cuboctahedra, corners with two AlGd9Mg2Al cuboctahedra, a faceface with one MgGd9MgAl2 cuboctahedra, and faces with two AlGd9Mg2Al cuboctahedra. There are a spread of Mg–Gd bond distances ranging from 3.35–3.60 Å. Both Mg–Al bond lengths are 2.99 Å. There are sixteen inequivalent Gd sites. In the first Gd site, Gd is bonded in a 3-coordinate geometry to two Mg, three Gd, three Ni, and one Al atom. There are a spread of Gd–Gd bond distances ranging from 3.48–3.56 Å. There are a spread of Gd–Ni bond distances ranging from 2.80–2.82 Å. The Gd–Al bond length is 3.50 Å. In the second Gd site, Gd is bonded in a 3-coordinate geometry to two Mg, three Gd, three Ni, and one Al atom. There are one shorter (3.47 Å) and two longer (3.55 Å) Gd–Gd bond lengths. There are one shorter (2.81 Å) and two longer (2.82 Å) Gd–Ni bond lengths. The Gd–Al bond length is 3.49 Å. In the third Gd site, Gd is bonded in a 3-coordinate geometry to one Mg, three Gd, three Ni, and two Al atoms. There are a spread of Gd–Gd bond distances ranging from 3.45–3.54 Å. There are a spread of Gd–Ni bond distances ranging from 2.81–2.83 Å. There are one shorter (3.41 Å) and one longer (3.43 Å) Gd–Al bond lengths. In the fourth Gd site, Gd is bonded in a 3-coordinate geometry to one Mg, three Gd, three Ni, and two Al atoms. There are two shorter (3.46 Å) and one longer (3.54 Å) Gd–Gd bond lengths. There are a spread of Gd–Ni bond distances ranging from 2.80–2.83 Å. There are one shorter (3.41 Å) and one longer (3.42 Å) Gd–Al bond lengths. In the fifth Gd site, Gd is bonded in a distorted bent 150 degrees geometry to one Mg, four Gd, two Ni, and one Al atom. There are a spread of Gd–Gd bond distances ranging from 3.59–3.64 Å. There are one shorter (2.80 Å) and one longer (2.83 Å) Gd–Ni bond lengths. The Gd–Al bond length is 3.54 Å. In the sixth Gd site, Gd is bonded in a distorted bent 150 degrees geometry to one Mg, four Gd, two Ni, and one Al atom. There are a spread of Gd–Gd bond distances ranging from 3.59–3.65 Å. There are one shorter (2.80 Å) and one longer (2.82 Å) Gd–Ni bond lengths. The Gd–Al bond length is 3.53 Å. In the seventh Gd site, Gd is bonded in a bent 150 degrees geometry to two Mg, four Gd, and two Ni atoms. There are a spread of Gd–Gd bond distances ranging from 3.64–3.67 Å. Both Gd–Ni bond lengths are 2.79 Å. In the eighth Gd site, Gd is bonded in a distorted bent 150 degrees geometry to one Mg, four Gd, two Ni, and one Al atom. There are a spread of Gd–Gd bond distances ranging from 3.58–3.65 Å. There are one shorter (2.81 Å) and one longer (2.84 Å) Gd–Ni bond lengths. The Gd–Al bond length is 3.52 Å. In the ninth Gd site, Gd is bonded in a distorted bent 150 degrees geometry to one Mg, four Gd, two Ni, and one Al atom. There are a spread of Gd–Gd bond distances ranging from 3.60–3.63 Å. There are one shorter (2.79 Å) and one longer (2.83 Å) Gd–Ni bond lengths. The Gd–Al bond length is 3.53 Å. In the tenth Gd site, Gd is bonded in a distorted bent 150 degrees geometry to four Gd, two Ni, and two Al atoms. There are a spread of Gd–Gd bond distances ranging from 3.56–3.59 Å. There are one shorter (2.83 Å) and one longer (2.84 Å) Gd–Ni bond lengths. There are one shorter (3.39 Å) and one longer (3.41 Å) Gd–Al bond lengths. In the eleventh Gd site, Gd is bonded in a 4-coordinate geometry to one Mg, ten Gd, two Ni, and one Al atom. There are a spread of Gd–Gd bond distances ranging from 3.56–3.59 Å. There are one shorter (3.47 Å) and one longer (3.51 Å) Gd–Ni bond lengths. The Gd–Al bond length is 3.25 Å. In the twelfth Gd site, Gd is bonded in a 4-coordinate geometry to one Mg, ten Gd, two Ni, and one Al atom. There are a spread of Gd–Gd bond distances ranging from 3.56–3.60 Å. There are one shorter (3.49 Å) and one longer (3.51 Å) Gd–Ni bond lengths. The Gd–Al bond length is 3.25 Å. In the thirteenth Gd site, Gd is bonded in a 4-coordinate geometry to ten Gd, two Ni, and two Al atoms. Both Gd–Gd bond lengths are 3.56 Å. Both Gd–Ni bond lengths are 3.51 Å. There are one shorter (3.30 Å) and one longer (3.33 Å) Gd–Al bond lengths. In the fourteenth Gd site, Gd is bonded in a 4-coordinate geometry to one Mg, ten Gd, two Ni, and one Al atom. There are one shorter (3.56 Å) and one longer (3.59 Å) Gd–Gd bond lengths. There are one shorter (3.49 Å) and one longer (3.52 Å) Gd–Ni bond lengths. The Gd–Al bond length is 3.25 Å. In the fifteenth Gd site, Gd is bonded in a 4-coordinate geometry to one Mg, ten Gd, two Ni, and one Al atom. The Gd–Gd bond length is 3.59 Å. There are one shorter (3.50 Å) and one longer (3.52 Å) Gd–Ni bond lengths. The Gd–Al bond length is 3.25 Å. In the sixteenth Gd site, Gd is bonded in a 4-coordinate geometry to two Mg, ten Gd, and two Ni atoms. There are one shorter (3.49 Å) and one longer (3.50 Å) Gd–Ni bond lengths. There are four inequivalent Ni sites. In the first Ni site, Ni is bonded in a 6-coordinate geometry to nine Gd atoms. In the second Ni site, Ni is bonded in a 6-coordinate geometry to nine Gd atoms. In the third Ni site, Ni is bonded in a 6-coordinate geometry to nine Gd atoms. In the fourth Ni site, Ni is bonded in a 6-coordinate geometry to nine Gd atoms. There are two inequivalent Al sites. In the first Al site, Al is bonded to two Mg, nine Gd, and one Al atom to form AlGd9Mg2Al cuboctahedra that share a cornercorner with one AlGd9Mg2Al cuboctahedra, corners with two MgGd9MgAl2 cuboctahedra, a faceface with one AlGd9Mg2Al cuboctahedra, and faces with two MgGd9MgAl2 cuboctahedra. The Al–Al bond length is 2.97 Å. In the second Al site, Al is bonded to two Mg, nine Gd, and one Al atom to form AlGd9Mg2Al cuboctahedra that share a cornercorner with one AlGd9Mg2Al cuboctahedra, corners with two MgGd9MgAl2 cuboctahedra, a faceface with one AlGd9Mg2Al cuboctahedra, and faces with two MgGd9MgAl2 cuboctahedra.

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2020-06-05. Materials Data on Gd8MgAlNi2 by Materials Project. https://doi.org/10.17188/1719905

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