DOE OSTI2020
DyNi4Al crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Dy is bonded in a 6-coordinate geometry to fifteen Ni and three equivalent Al atoms. There are three shorter (2.91 Å) and twelve longer (3.17 Å) Dy–Ni bond lengths. All Dy–Al bond lengths are 2.91 Å. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded to three equivalent Dy, six equivalent Ni, and three equivalent Al atoms to form NiDy3Al3Ni6 cuboctahedra that share corners with nine equivalent AlDy3Ni9 cuboctahedra, corners with twelve equivalent NiDy4Al2Ni6 cuboctahedra, edges with six equivalent NiDy3Al3Ni6 cuboctahedra, faces with three equivalent AlDy3Ni9 cuboctahedra, and faces with twenty NiDy3Al3Ni6 cuboctahedra. All Ni–Ni bond lengths are 2.40 Å. All Ni–Al bond lengths are 2.91 Å. In the second Ni site, Ni is bonded to four equivalent Dy, six Ni, and two equivalent Al atoms to form distorted NiDy4Al2Ni6 cuboctahedra that share corners with four equivalent AlDy3Ni9 cuboctahedra, corners with twenty NiDy3Al3Ni6 cuboctahedra, edges with ten equivalent NiDy4Al2Ni6 cuboctahedra, faces with six equivalent AlDy3Ni9 cuboctahedra, and faces with sixteen NiDy3Al3Ni6 cuboctahedra. There are two shorter (2.48 Å) and two longer (2.55 Å) Ni–Ni bond lengths. Both Ni–Al bond lengths are 2.43 Å. Al is bonded to three equivalent Dy and nine Ni atoms to form distorted AlDy3Ni9 cuboctahedra that share corners with twenty-one NiDy3Al3Ni6 cuboctahedra, edges with six equivalent AlDy3Ni9 cuboctahedra, faces with two equivalent AlDy3Ni9 cuboctahedra, and faces with twenty-one NiDy3Al3Ni6 cuboctahedra.