Materials Data on Tm3AlNi8 by Materials Project

Abstract

Tm3Ni8Al crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Tm sites. In the first Tm site, Tm is bonded in a 12-coordinate geometry to twelve Ni atoms. There are a spread of Tm–Ni bond distances ranging from 2.85–3.03 Å. In the second Tm site, Tm is bonded in a 6-coordinate geometry to fifteen Ni and three equivalent Al atoms. There are three shorter (2.89 Å) and twelve longer (3.19 Å) Tm–Ni bond lengths. All Tm–Al bond lengths are 2.89 Å. There are three inequivalent Ni sites. In the first Ni site, Ni is bonded to five Tm, six Ni, and one Al atom to form distorted NiTm5AlNi6 cuboctahedra that share corners with two equivalent AlTm3Ni9 cuboctahedra, corners with nineteen NiTm5AlNi6 cuboctahedra, edges with eight equivalent NiTm5AlNi6 cuboctahedra, faces with three equivalent AlTm3Ni9 cuboctahedra, and faces with seventeen NiTm5AlNi6 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.45–2.52 Å. The Ni–Al bond length is 2.44 Å. In the second Ni site, Ni is bonded to three equivalent Tm, six equivalent Ni, and three equivalent Al atoms to form NiTm3Al3Ni6 cuboctahedra that share corners with three equivalent AlTm3Ni9 cuboctahedra, corners with twelve equivalent NiTm5AlNi6 cuboctahedra, edges with six equivalent NiTm3Al3Ni6 cuboctahedra, faces with three equivalent AlTm3Ni9 cuboctahedra, and faces with twenty NiTm5AlNi6 cuboctahedra. All Ni–Al bond lengths are 2.89 Å. In the third Ni site, Ni is bonded to six equivalent Tm and six equivalent Ni atoms to form NiTm6Ni6 cuboctahedra that share corners with six equivalent AlTm3Ni9 cuboctahedra, corners with twelve equivalent NiTm5AlNi6 cuboctahedra, edges with six equivalent NiTm6Ni6 cuboctahedra, and faces with twenty NiTm5AlNi6 cuboctahedra. Al is bonded to three equivalent Tm and nine Ni atoms to form distorted AlTm3Ni9 cuboctahedra that share corners with twenty-one NiTm5AlNi6 cuboctahedra, edges with six equivalent AlTm3Ni9 cuboctahedra, and faces with twenty-one NiTm5AlNi6 cuboctahedra.