Materials Data on CeAlNi4 by Materials Project
CeNi4Al crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Ce is bonded in a 6-coordinate geometry to fifteen Ni and three equivalent Al atoms. There are three shorter (2.95 Å) and twelve longer (3.22 Å) Ce–Ni bond lengths. All Ce–Al bond lengths are 2.95 Å. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded to three equivalent Ce, six equivalent Ni, and three equivalent Al atoms to form NiCe3Al3Ni6 cuboctahedra that share corners with nine equivalent AlCe3Ni9 cuboctahedra, corners with twelve equivalent NiCe4Al2Ni6 cuboctahedra, edges with six equivalent NiCe3Al3Ni6 cuboctahedra, faces with three equivalent AlCe3Ni9 cuboctahedra, and faces with twenty NiCe3Al3Ni6 cuboctahedra. All Ni–Ni bond lengths are 2.43 Å. All Ni–Al bond lengths are 2.95 Å. In the second Ni site, Ni is bonded to four equivalent Ce, six Ni, and two equivalent Al atoms to form distorted NiCe4Al2Ni6 cuboctahedra that share corners with four equivalent AlCe3Ni9 cuboctahedra, corners with twenty NiCe3Al3Ni6 cuboctahedra, edges with ten equivalent NiCe4Al2Ni6 cuboctahedra, faces with six equivalent AlCe3Ni9 cuboctahedra, and faces with sixteen NiCe3Al3Ni6 cuboctahedra. There are two shorter (2.52 Å) and two longer (2.59 Å) Ni–Ni bond lengths. Both Ni–Al bond lengths are 2.46 Å. Al is bonded to three equivalent Ce and nine Ni atoms to form distorted AlCe3Ni9 cuboctahedra that share corners with twenty-one NiCe3Al3Ni6 cuboctahedra, edges with six equivalent AlCe3Ni9 cuboctahedra, faces with two equivalent AlCe3Ni9 cuboctahedra, and faces with twenty-one NiCe3Al3Ni6 cuboctahedra.