DOE OSTI2020
Y5Bi3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are four inequivalent Y sites. In the first Y site, Y is bonded to five Bi atoms to form distorted YBi5 square pyramids that share corners with five equivalent YBi6 octahedra, corners with four equivalent YBi5 trigonal bipyramids, an edgeedge with one YBi6 octahedra, edges with two equivalent YBi5 square pyramids, an edgeedge with one YBi5 trigonal bipyramid, a faceface with one YBi6 octahedra, and a faceface with one YBi5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 37–45°. There are a spread of Y–Bi bond distances ranging from 3.18–3.27 Å. In the second Y site, Y is bonded to six Bi atoms to form distorted YBi6 octahedra that share corners with five equivalent YBi5 square pyramids, corners with six equivalent YBi5 trigonal bipyramids, an edgeedge with one YBi5 square pyramid, edges with two equivalent YBi5 trigonal bipyramids, faces with two equivalent YBi6 octahedra, and a faceface with one YBi5 square pyramid. There are a spread of Y–Bi bond distances ranging from 3.14–3.46 Å. In the third Y site, Y is bonded in a 5-coordinate geometry to five Bi atoms. There are a spread of Y–Bi bond distances ranging from 3.12–3.53 Å. In the fourth Y site, Y is bonded to five Bi atoms to form distorted YBi5 trigonal bipyramids that share corners with six equivalent YBi6 octahedra, corners with four equivalent YBi5 square pyramids, edges with two equivalent YBi6 octahedra, an edgeedge with one YBi5 square pyramid, edges with two equivalent YBi5 trigonal bipyramids, and a faceface with one YBi5 square pyramid. The corner-sharing octahedra tilt angles range from 31–41°. There are a spread of Y–Bi bond distances ranging from 3.15–3.40 Å. There are two inequivalent Bi sites. In the first Bi site, Bi is bonded in a 9-coordinate geometry to nine Y atoms. In the second Bi site, Bi is bonded in a 8-coordinate geometry to eight Y atoms.