Ho3Gd is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to four equivalent Ho(1), four equivalent Ho(2), and four equivalent Gd(1) atoms to form HoGd4Ho8 cuboctahedra that share corners with twelve equivalent Ho(1)Gd4Ho8 cuboctahedra, edges with eight equivalent Ho(1)Gd4Ho8 cuboctahedra, edges with eight equivalent Ho(2)Gd4Ho8 cuboctahedra, edges with eight equivalent Gd(1)Ho12 cuboctahedra, faces with four equivalent Ho(2)Gd4Ho8 cuboctahedra, faces with four equivalent Gd(1)Ho12 cuboctahedra, and faces with ten equivalent Ho(1)Gd4Ho8 cuboctahedra. In the second Ho site, Ho(2) is bonded to eight equivalent Ho(1) and four equivalent Gd(1) atoms to form HoGd4Ho8 cuboctahedra that share corners with four equivalent Ho(2)Gd4Ho8 cuboctahedra, corners with eight equivalent Gd(1)Ho12 cuboctahedra, edges with eight equivalent Ho(2)Gd4Ho8 cuboctahedra, edges with sixteen equivalent Ho(1)Gd4Ho8 cuboctahedra, faces with four equivalent Ho(2)Gd4Ho8 cuboctahedra, faces with six equivalent Gd(1)Ho12 cuboctahedra, and faces with eight equivalent Ho(1)Gd4Ho8 cuboctahedra. Gd(1) is bonded to four equivalent Ho(2) and eight equivalent Ho(1) atoms to form GdHo12 cuboctahedra that share corners with four equivalent Gd(1)Ho12 cuboctahedra, corners with eight equivalent Ho(2)Gd4Ho8 cuboctahedra, edges with eight equivalent Gd(1)Ho12 cuboctahedra, edges with sixteen equivalent Ho(1)Gd4Ho8 cuboctahedra, faces with four equivalent Gd(1)Ho12 cuboctahedra, faces with six equivalent Ho(2)Gd4Ho8 cuboctahedra, and faces with eight equivalent Ho(1)Gd4Ho8 cuboctahedra.
Ho3Gd is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to four equivalent Ho(1), four equivalent Ho(2), and four equivalent Gd(1) atoms to form HoGd4Ho8 cuboctahedra that share corners with twelve equivalent Ho(1)Gd4Ho8 cuboctahedra, edges with eight equivalent Ho(1)Gd4Ho8 cuboctahedra, edges with eight equivalent Ho(2)Gd4Ho8 cuboctahedra, edges with eight equivalent Gd(1)Ho12 cuboctahedra, faces with four equivalent Ho(2)Gd4Ho8 cuboctahedra, faces with four equivalent Gd(1)Ho12 cuboctahedra, and faces with ten equivalent Ho(1)Gd4Ho8 cuboctahedra. All Ho(1)-Ho(1) bond lengths are 3.54 Å. All Ho(1)-Ho(2) bond lengths are 3.55 Å. All Ho(1)-Gd(1) bond lengths are 3.55 Å. In the second Ho site, Ho(2) is bonded to eight equivalent Ho(1) and four equivalent Gd(1) atoms to form HoGd4Ho8 cuboctahedra that share corners with four equivalent Ho(2)Gd4Ho8 cuboctahedra, corners with eight equivalent Gd(1)Ho12 cuboctahedra, edges with eight equivalent Ho(2)Gd4Ho8 cuboctahedra, edges with sixteen equivalent Ho(1)Gd4Ho8 cuboctahedra, faces with four equivalent Ho(2)Gd4Ho8 cuboctahedra, faces with six equivalent Gd(1)Ho12 cuboctahedra, and faces with eight equivalent Ho(1)Gd4Ho8 cuboctahedra. All Ho(2)-Gd(1) bond lengths are 3.54 Å. Gd(1) is bonded to four equivalent Ho(2) and eight equivalent Ho(1) atoms to form GdHo12 cuboctahedra that share corners with four equivalent Gd(1)Ho12 cuboctahedra, corners with eight equivalent Ho(2)Gd4Ho8 cuboctahedra, edges with eight equivalent Gd(1)Ho12 cuboctahedra, edges with sixteen equivalent Ho(1)Gd4Ho8 cuboctahedra, faces with four equivalent Gd(1)Ho12 cuboctahedra, faces with six equivalent Ho(2)Gd4Ho8 cuboctahedra, and faces with eight equivalent Ho(1)Gd4Ho8 cuboctahedra.