DOE OSTI2020
Ho3As is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded to eight Ho and four equivalent As atoms to form distorted HoHo8As4 cuboctahedra that share corners with twelve equivalent HoHo8As4 cuboctahedra, edges with eight equivalent HoHo8As4 cuboctahedra, edges with eight equivalent AsHo12 cuboctahedra, faces with four equivalent AsHo12 cuboctahedra, and faces with ten equivalent HoHo8As4 cuboctahedra. There are four shorter (3.16 Å) and four longer (3.41 Å) Ho–Ho bond lengths. All Ho–As bond lengths are 3.41 Å. In the second Ho site, Ho is bonded in a square co-planar geometry to eight equivalent Ho and four equivalent As atoms. All Ho–As bond lengths are 3.16 Å. As is bonded to twelve Ho atoms to form AsHo12 cuboctahedra that share corners with four equivalent AsHo12 cuboctahedra, edges with eight equivalent AsHo12 cuboctahedra, edges with sixteen equivalent HoHo8As4 cuboctahedra, faces with four equivalent AsHo12 cuboctahedra, and faces with eight equivalent HoHo8As4 cuboctahedra.