Materials Data on Y2Ni7 by Materials Project
Y2Ni7 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Y sites. In the first Y site, Y is bonded in a 12-coordinate geometry to twelve Ni atoms. There are a spread of Y–Ni bond distances ranging from 2.81–3.15 Å. In the second Y site, Y is bonded in a 6-coordinate geometry to eighteen Ni atoms. There are a spread of Y–Ni bond distances ranging from 2.85–3.25 Å. There are five inequivalent Ni sites. In the first Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Y and six Ni atoms. There are three shorter (2.41 Å) and three longer (2.44 Å) Ni–Ni bond lengths. In the second Ni site, Ni is bonded to six equivalent Y and six equivalent Ni atoms to form NiY6Ni6 cuboctahedra that share corners with twelve equivalent NiY5Ni7 cuboctahedra, edges with six equivalent NiY6Ni6 cuboctahedra, and faces with eighteen equivalent NiY5Ni7 cuboctahedra. All Ni–Ni bond lengths are 2.52 Å. In the third Ni site, Ni is bonded to four equivalent Y and eight Ni atoms to form NiY4Ni8 cuboctahedra that share corners with sixteen NiY5Ni7 cuboctahedra, edges with ten NiY5Ni7 cuboctahedra, and faces with ten NiY4Ni8 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.43–2.48 Å. In the fourth Ni site, Ni is bonded to five Y and seven Ni atoms to form distorted NiY5Ni7 cuboctahedra that share corners with seventeen NiY6Ni6 cuboctahedra, edges with eight NiY4Ni8 cuboctahedra, and faces with fourteen NiY6Ni6 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.44–2.47 Å. In the fifth Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Y and six Ni atoms.