DOE OSTI2020
Y5Ni2Bi crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Y sites. In the first Y site, Y is bonded to four equivalent Ni and two equivalent Bi atoms to form distorted YNi4Bi2 octahedra that share corners with six equivalent YNi4Bi2 octahedra, corners with sixteen equivalent YNi3Bi2 trigonal bipyramids, and faces with eight equivalent YNi3Bi2 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 0–51°. All Y–Ni bond lengths are 3.02 Å. Both Y–Bi bond lengths are 3.41 Å. In the second Y site, Y is bonded to three equivalent Ni and two equivalent Bi atoms to form distorted YNi3Bi2 trigonal bipyramids that share corners with four equivalent YNi4Bi2 octahedra, corners with twelve equivalent YNi3Bi2 trigonal bipyramids, edges with seven equivalent YNi3Bi2 trigonal bipyramids, faces with two equivalent YNi4Bi2 octahedra, and a faceface with one YNi3Bi2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 42–62°. There are two shorter (2.90 Å) and one longer (2.98 Å) Y–Ni bond lengths. Both Y–Bi bond lengths are 3.31 Å. Ni is bonded in a 8-coordinate geometry to eight Y atoms. Bi is bonded in a distorted q6 geometry to ten Y atoms.