Materials Data on HoNi3 by Materials Project
HoNi3 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded in a 12-coordinate geometry to twelve Ni atoms. There are a spread of Ho–Ni bond distances ranging from 2.83–3.07 Å. In the second Ho site, Ho is bonded in a distorted hexagonal planar geometry to eighteen Ni atoms. There are six shorter (2.85 Å) and twelve longer (3.17 Å) Ho–Ni bond lengths. There are three inequivalent Ni sites. In the first Ni site, Ni is bonded to five Ho and seven Ni atoms to form a mixture of distorted edge, corner, and face-sharing NiHo5Ni7 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.44–2.50 Å. In the second Ni site, Ni is bonded to six equivalent Ho and six equivalent Ni atoms to form NiHo6Ni6 cuboctahedra that share corners with twelve equivalent NiHo5Ni7 cuboctahedra, edges with six equivalent NiHo6Ni6 cuboctahedra, and faces with eighteen equivalent NiHo5Ni7 cuboctahedra. In the third Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Ho and six equivalent Ni atoms.