Materials Data on AcSc3 by Materials Project
AcSc3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ac is bonded to twelve Sc atoms to form AcSc12 cuboctahedra that share corners with six equivalent AcSc12 cuboctahedra, corners with twelve ScAc4Sc8 cuboctahedra, edges with eighteen ScAc4Sc8 cuboctahedra, faces with eight equivalent AcSc12 cuboctahedra, and faces with twelve ScAc4Sc8 cuboctahedra. All Ac–Sc bond lengths are 3.49 Å. There are three inequivalent Sc sites. In the first Sc site, Sc is bonded to four equivalent Ac and eight Sc atoms to form distorted ScAc4Sc8 cuboctahedra that share corners with four equivalent AcSc12 cuboctahedra, corners with fourteen ScAc4Sc8 cuboctahedra, edges with six equivalent AcSc12 cuboctahedra, edges with twelve ScAc4Sc8 cuboctahedra, faces with four equivalent AcSc12 cuboctahedra, and faces with sixteen ScAc4Sc8 cuboctahedra. There are a spread of Sc–Sc bond distances ranging from 3.33–3.64 Å. In the second Sc site, Sc is bonded to four equivalent Ac and eight Sc atoms to form distorted ScAc4Sc8 cuboctahedra that share corners with four equivalent AcSc12 cuboctahedra, corners with fourteen ScAc4Sc8 cuboctahedra, edges with six equivalent AcSc12 cuboctahedra, edges with twelve ScAc4Sc8 cuboctahedra, faces with four equivalent AcSc12 cuboctahedra, and faces with sixteen ScAc4Sc8 cuboctahedra. There are a spread of Sc–Sc bond distances ranging from 3.33–3.64 Å. In the third Sc site, Sc is bonded to four equivalent Ac and eight Sc atoms to form distorted ScAc4Sc8 cuboctahedra that share corners with four equivalent AcSc12 cuboctahedra, corners with fourteen ScAc4Sc8 cuboctahedra, edges with six equivalent AcSc12 cuboctahedra, edges with twelve ScAc4Sc8 cuboctahedra, faces with four equivalent AcSc12 cuboctahedra, and faces with sixteen ScAc4Sc8 cuboctahedra. Both Sc–Sc bond lengths are 3.38 Å.