DOE OSTI2020
Ho4PdGa12 crystallizes in the cubic Im-3m space group. The structure is three-dimensional. Ho is bonded to twelve Ga atoms to form HoGa12 cuboctahedra that share corners with twelve equivalent HoGa12 cuboctahedra, edges with twelve equivalent GaHo4Ga8 cuboctahedra, faces with six equivalent HoGa12 cuboctahedra, faces with six equivalent GaHo4Ga8 cuboctahedra, and faces with two equivalent PdGa6 octahedra. There are six shorter (3.05 Å) and six longer (3.08 Å) Ho–Ga bond lengths. Pd is bonded to six equivalent Ga atoms to form PdGa6 octahedra that share corners with twenty-four equivalent GaHo4Ga8 cuboctahedra and faces with eight equivalent HoGa12 cuboctahedra. All Pd–Ga bond lengths are 2.56 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded to four equivalent Ho and eight Ga atoms to form distorted GaHo4Ga8 cuboctahedra that share corners with four equivalent GaHo4Ga8 cuboctahedra, corners with four equivalent PdGa6 octahedra, edges with eight equivalent HoGa12 cuboctahedra, edges with eight equivalent GaHo4Ga8 cuboctahedra, faces with four equivalent HoGa12 cuboctahedra, and faces with six equivalent GaHo4Ga8 cuboctahedra. The corner-sharing octahedral tilt angles are 51°. There are four shorter (2.79 Å) and four longer (3.05 Å) Ga–Ga bond lengths. In the second Ga site, Ga is bonded in a 1-coordinate geometry to four equivalent Ho, one Pd, and four equivalent Ga atoms.