Ac3Sc is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Ac(1) is bonded to eight equivalent Ac(1) and four equivalent Sc(1) atoms to form distorted AcAc8Sc4 cuboctahedra that share corners with four equivalent Sc(1)Ac12 cuboctahedra, corners with fourteen equivalent Ac(1)Ac8Sc4 cuboctahedra, edges with six equivalent Sc(1)Ac12 cuboctahedra, edges with twelve equivalent Ac(1)Ac8Sc4 cuboctahedra, faces with four equivalent Sc(1)Ac12 cuboctahedra, and faces with sixteen equivalent Ac(1)Ac8Sc4 cuboctahedra. Sc(1) is bonded to twelve equivalent Ac(1) atoms to form ScAc12 cuboctahedra that share corners with six equivalent Sc(1)Ac12 cuboctahedra, corners with twelve equivalent Ac(1)Ac8Sc4 cuboctahedra, edges with eighteen equivalent Ac(1)Ac8Sc4 cuboctahedra, faces with eight equivalent Sc(1)Ac12 cuboctahedra, and faces with twelve equivalent Ac(1)Ac8Sc4 cuboctahedra.
Ac3Sc is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Ac(1) is bonded to eight equivalent Ac(1) and four equivalent Sc(1) atoms to form distorted AcAc8Sc4 cuboctahedra that share corners with four equivalent Sc(1)Ac12 cuboctahedra, corners with fourteen equivalent Ac(1)Ac8Sc4 cuboctahedra, edges with six equivalent Sc(1)Ac12 cuboctahedra, edges with twelve equivalent Ac(1)Ac8Sc4 cuboctahedra, faces with four equivalent Sc(1)Ac12 cuboctahedra, and faces with sixteen equivalent Ac(1)Ac8Sc4 cuboctahedra. There are a spread of Ac(1)-Ac(1) bond distances ranging from 3.75-3.98 Å. There are two shorter (3.76 Å) and two longer (3.86 Å) Ac(1)-Sc(1) bond lengths. Sc(1) is bonded to twelve equivalent Ac(1) atoms to form ScAc12 cuboctahedra that share corners with six equivalent Sc(1)Ac12 cuboctahedra, corners with twelve equivalent Ac(1)Ac8Sc4 cuboctahedra, edges with eighteen equivalent Ac(1)Ac8Sc4 cuboctahedra, faces with eight equivalent Sc(1)Ac12 cuboctahedra, and faces with twelve equivalent Ac(1)Ac8Sc4 cuboctahedra.