DOE OSTI2020
Ni3Hg crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Ni sites. In the first Ni site, Ni is bonded to eight Ni and four equivalent Hg atoms to form NiNi8Hg4 cuboctahedra that share corners with four equivalent HgNi12 cuboctahedra, corners with fourteen equivalent NiNi8Hg4 cuboctahedra, edges with six equivalent HgNi12 cuboctahedra, edges with twelve NiNi8Hg4 cuboctahedra, faces with four equivalent HgNi12 cuboctahedra, and faces with sixteen NiNi8Hg4 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.49–2.85 Å. There are two shorter (2.67 Å) and two longer (2.69 Å) Ni–Hg bond lengths. In the second Ni site, Ni is bonded to eight Ni and four equivalent Hg atoms to form NiNi8Hg4 cuboctahedra that share corners with four equivalent HgNi12 cuboctahedra, corners with fourteen NiNi8Hg4 cuboctahedra, edges with six equivalent HgNi12 cuboctahedra, edges with twelve NiNi8Hg4 cuboctahedra, faces with four equivalent HgNi12 cuboctahedra, and faces with sixteen NiNi8Hg4 cuboctahedra. There are one shorter (2.49 Å) and one longer (2.85 Å) Ni–Ni bond lengths. There are two shorter (2.67 Å) and two longer (2.69 Å) Ni–Hg bond lengths. Hg is bonded to twelve Ni atoms to form HgNi12 cuboctahedra that share corners with six equivalent HgNi12 cuboctahedra, corners with twelve NiNi8Hg4 cuboctahedra, edges with eighteen NiNi8Hg4 cuboctahedra, faces with eight equivalent HgNi12 cuboctahedra, and faces with twelve NiNi8Hg4 cuboctahedra.