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Hf3Pb is Uranium Silicide-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Hf is bonded in a distorted see-saw-like geometry to four equivalent Pb atoms. There are two shorter (3.17 Å) and two longer (3.18 Å) Hf–Pb bond lengths. Pb is bonded to twelve equivalent Hf atoms to form a mixture of corner and face-sharing PbHf12 cuboctahedra.
Hf5Pb crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are three inequivalent Hf sites. In the first Hf site, Hf is bonded to twelve Hf atoms to form HfHf12 cuboctahedra that share corners with four equivalent PbHf8Pb4 cuboctahedra, corners with eight equivalent HfHf12 cuboctahedra, edges with four equivalent PbHf8Pb4 cuboctahedra, edges with twenty HfHf12 cuboctahedra, a faceface with one PbHf8Pb4 cuboctahedra, and faces with seventeen HfHf12 cuboctahedra. There are a spread of Hf–Hf bond distances ranging from 3.11–3.20 Å. In the second Hf site, Hf is bonded to eight Hf and four equivalent Pb atoms to form distorted HfHf8Pb4 cuboctahedra that share corners with twelve HfHf8Pb4 cuboctahedra, edges with eight equivalent PbHf8Pb4 cuboctahedra, edges with sixteen HfHf12 cuboctahedra, faces with four equivalent PbHf8Pb4 cuboctahedra, and faces with fourteen HfHf12 cuboctahedra. All Hf–Hf bond lengths are 3.20 Å. All Hf–Pb bond lengths are 3.33 Å. In the third Hf site, Hf is bonded to twelve Hf atoms to form HfHf12 cuboctahedra that share corners with twelve HfHf8Pb4 cuboctahedra, edges with twenty-four HfHf12 cuboctahedra, and faces with eighteen HfHf12 cuboctahedra. All Hf–Hf bond lengths are 3.20 Å. Pb is bonded to eight equivalent Hf and four equivalent Pb atoms to form distorted PbHf8Pb4 cuboctahedra that share corners with four equivalent PbHf8Pb4 cuboctahedra, corners with eight equivalent HfHf12 cuboctahedra, edges with twenty-four HfHf12 cuboctahedra, faces with eight equivalent PbHf8Pb4 cuboctahedra, and faces with ten HfHf12 cuboctahedra. All Pb–Pb bond lengths are 3.20 Å.