Materials Data on HoSiNi4 by Materials Project

Abstract

HoNi4Si is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Ho is bonded in a 6-coordinate geometry to fourteen Ni and four equivalent Si atoms. There are a spread of Ho–Ni bond distances ranging from 2.79–3.10 Å. All Ho–Si bond lengths are 3.20 Å. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Ho, five Ni, and two equivalent Si atoms. There are four shorter (2.46 Å) and one longer (2.56 Å) Ni–Ni bond lengths. Both Ni–Si bond lengths are 2.35 Å. In the second Ni site, Ni is bonded to four equivalent Ho, six Ni, and two equivalent Si atoms to form NiHo4Si2Ni6 cuboctahedra that share corners with four equivalent SiHo4Ni8 cuboctahedra, corners with twelve equivalent NiHo4Si2Ni6 cuboctahedra, edges with four equivalent SiHo4Ni8 cuboctahedra, edges with six equivalent NiHo4Si2Ni6 cuboctahedra, faces with four equivalent SiHo4Ni8 cuboctahedra, and faces with six equivalent NiHo4Si2Ni6 cuboctahedra. Both Ni–Ni bond lengths are 2.52 Å. Both Ni–Si bond lengths are 2.40 Å. Si is bonded to four equivalent Ho and eight Ni atoms to form distorted SiHo4Ni8 cuboctahedra that share corners with eight equivalent NiHo4Si2Ni6 cuboctahedra, corners with eight equivalent SiHo4Ni8 cuboctahedra, edges with two equivalent SiHo4Ni8 cuboctahedra, edges with eight equivalent NiHo4Si2Ni6 cuboctahedra, faces with two equivalent SiHo4Ni8 cuboctahedra, and faces with eight equivalent NiHo4Si2Ni6 cuboctahedra.