DOE OSTI2020
Sc3Pb is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Sc sites. In the first Sc site, Sc is bonded to eight Sc and four equivalent Pb atoms to form distorted ScSc8Pb4 cuboctahedra that share corners with twelve equivalent ScSc8Pb4 cuboctahedra, edges with eight equivalent ScSc8Pb4 cuboctahedra, edges with eight equivalent PbSc12 cuboctahedra, faces with four equivalent PbSc12 cuboctahedra, and faces with ten equivalent ScSc8Pb4 cuboctahedra. There are four shorter (3.11 Å) and four longer (3.31 Å) Sc–Sc bond lengths. All Sc–Pb bond lengths are 3.31 Å. In the second Sc site, Sc is bonded in a square co-planar geometry to eight equivalent Sc and four equivalent Pb atoms. All Sc–Pb bond lengths are 3.11 Å. Pb is bonded to twelve Sc atoms to form PbSc12 cuboctahedra that share corners with four equivalent PbSc12 cuboctahedra, edges with eight equivalent PbSc12 cuboctahedra, edges with sixteen equivalent ScSc8Pb4 cuboctahedra, faces with four equivalent PbSc12 cuboctahedra, and faces with eight equivalent ScSc8Pb4 cuboctahedra.