AcSc3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Ac(1) is bonded to twelve Sc(1,1,1) atoms to form AcSc12 cuboctahedra that share corners with six equivalent Ac(1)Sc12 cuboctahedra; corners with twelve Sc(1,1)Ac4Sc8 cuboctahedra; edges with eighteen Sc(1,1,1)Ac4Sc8 cuboctahedra; faces with eight equivalent Ac(1)Sc12 cuboctahedra; and faces with twelve Sc(1,1,1)Ac4Sc8 cuboctahedra. There are three inequivalent Sc sites. In the first Sc site, Sc(1) is bonded to four equivalent Ac(1) and eight Sc(1,1) atoms to form distorted ScAc4Sc8 cuboctahedra that share corners with four equivalent Ac(1)Sc12 cuboctahedra; corners with fourteen Sc(1,1,1)Ac4Sc8 cuboctahedra; edges with six equivalent Ac(1)Sc12 cuboctahedra; edges with twelve Sc(1,1)Ac4Sc8 cuboctahedra; faces with four equivalent Ac(1)Sc12 cuboctahedra; and faces with sixteen Sc(1,1,1)Ac4Sc8 cuboctahedra. In the second Sc site, Sc(1) is bonded to four equivalent Ac(1) and eight Sc(1,1,1) atoms to form distorted ScAc4Sc8 cuboctahedra that share corners with four equivalent Ac(1)Sc12 cuboctahedra; corners with fourteen Sc(1,1,1)Ac4Sc8 cuboctahedra; edges with six equivalent Ac(1)Sc12 cuboctahedra; edges with twelve Sc(1,1,1)Ac4Sc8 cuboctahedra; faces with four equivalent Ac(1)Sc12 cuboctahedra; and faces with sixteen Sc(1,1,1)Ac4Sc8 cuboctahedra. In the third Sc site, Sc(1) is bonded to four equivalent Ac(1) and eight Sc(1,1) atoms to form distorted ScAc4Sc8 cuboctahedra that share corners with four equivalent Ac(1)Sc12 cuboctahedra; corners with fourteen Sc(1,1,1)Ac4Sc8 cuboctahedra; edges with six equivalent Ac(1)Sc12 cuboctahedra; edges with twelve Sc(1,1)Ac4Sc8 cuboctahedra; faces with four equivalent Ac(1)Sc12 cuboctahedra; and faces with sixteen Sc(1,1,1)Ac4Sc8 cuboctahedra.
AcSc3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Ac(1) is bonded to twelve Sc(1,1,1) atoms to form AcSc12 cuboctahedra that share corners with six equivalent Ac(1)Sc12 cuboctahedra; corners with twelve Sc(1,1)Ac4Sc8 cuboctahedra; edges with eighteen Sc(1,1,1)Ac4Sc8 cuboctahedra; faces with eight equivalent Ac(1)Sc12 cuboctahedra; and faces with twelve Sc(1,1,1)Ac4Sc8 cuboctahedra. All Ac(1)-Sc(1,1,1) bond lengths are 3.49 Å. There are three inequivalent Sc sites. In the first Sc site, Sc(1) is bonded to four equivalent Ac(1) and eight Sc(1,1) atoms to form distorted ScAc4Sc8 cuboctahedra that share corners with four equivalent Ac(1)Sc12 cuboctahedra; corners with fourteen Sc(1,1,1)Ac4Sc8 cuboctahedra; edges with six equivalent Ac(1)Sc12 cuboctahedra; edges with twelve Sc(1,1)Ac4Sc8 cuboctahedra; faces with four equivalent Ac(1)Sc12 cuboctahedra; and faces with sixteen Sc(1,1,1)Ac4Sc8 cuboctahedra. There are a spread of Sc(1)-Sc(1,1) bond distances ranging from 3.33-3.64 Å. In the second Sc site, Sc(1) is bonded to four equivalent Ac(1) and eight Sc(1,1,1) atoms to form distorted ScAc4Sc8 cuboctahedra that share corners with four equivalent Ac(1)Sc12 cuboctahedra; corners with fourteen Sc(1,1,1)Ac4Sc8 cuboctahedra; edges with six equivalent Ac(1)Sc12 cuboctahedra; edges with twelve Sc(1,1,1)Ac4Sc8 cuboctahedra; faces with four equivalent Ac(1)Sc12 cuboctahedra; and faces with sixteen Sc(1,1,1)Ac4Sc8 cuboctahedra. There are a spread of Sc(1)-Sc(1,1) bond distances ranging from 3.33-3.64 Å. In the third Sc site, Sc(1) is bonded to four equivalent Ac(1) and eight Sc(1,1) atoms to form distorted ScAc4Sc8 cuboctahedra that share corners with four equivalent Ac(1)Sc12 cuboctahedra; corners with fourteen Sc(1,1,1)Ac4Sc8 cuboctahedra; edges with six equivalent Ac(1)Sc12 cuboctahedra; edges with twelve Sc(1,1)Ac4Sc8 cuboctahedra; faces with four equivalent Ac(1)Sc12 cuboctahedra; and faces with sixteen Sc(1,1,1)Ac4Sc8 cuboctahedra.