AcPm3 is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. Ac(1) is bonded to four equivalent Pm(2) and eight equivalent Pm(1) atoms to form AcPm12 cuboctahedra that share corners with four equivalent Ac(1)Pm12 cuboctahedra, corners with eight equivalent Pm(2)Ac4Pm8 cuboctahedra, edges with eight equivalent Ac(1)Pm12 cuboctahedra, edges with sixteen equivalent Pm(1)Ac4Pm8 cuboctahedra, faces with four equivalent Ac(1)Pm12 cuboctahedra, faces with six equivalent Pm(2)Ac4Pm8 cuboctahedra, and faces with eight equivalent Pm(1)Ac4Pm8 cuboctahedra. There are two inequivalent Pm sites. In the first Pm site, Pm(1) is bonded to four equivalent Ac(1), four equivalent Pm(1), and four equivalent Pm(2) atoms to form PmAc4Pm8 cuboctahedra that share corners with twelve equivalent Pm(1)Ac4Pm8 cuboctahedra, edges with eight equivalent Ac(1)Pm12 cuboctahedra, edges with eight equivalent Pm(1)Ac4Pm8 cuboctahedra, edges with eight equivalent Pm(2)Ac4Pm8 cuboctahedra, faces with four equivalent Ac(1)Pm12 cuboctahedra, faces with four equivalent Pm(2)Ac4Pm8 cuboctahedra, and faces with ten equivalent Pm(1)Ac4Pm8 cuboctahedra. In the second Pm site, Pm(2) is bonded to four equivalent Ac(1) and eight equivalent Pm(1) atoms to form PmAc4Pm8 cuboctahedra that share corners with four equivalent Pm(2)Ac4Pm8 cuboctahedra, corners with eight equivalent Ac(1)Pm12 cuboctahedra, edges with eight equivalent Pm(2)Ac4Pm8 cuboctahedra, edges with sixteen equivalent Pm(1)Ac4Pm8 cuboctahedra, faces with four equivalent Pm(2)Ac4Pm8 cuboctahedra, faces with six equivalent Ac(1)Pm12 cuboctahedra, and faces with eight equivalent Pm(1)Ac4Pm8 cuboctahedra.
AcPm3 is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. Ac(1) is bonded to four equivalent Pm(2) and eight equivalent Pm(1) atoms to form AcPm12 cuboctahedra that share corners with four equivalent Ac(1)Pm12 cuboctahedra, corners with eight equivalent Pm(2)Ac4Pm8 cuboctahedra, edges with eight equivalent Ac(1)Pm12 cuboctahedra, edges with sixteen equivalent Pm(1)Ac4Pm8 cuboctahedra, faces with four equivalent Ac(1)Pm12 cuboctahedra, faces with six equivalent Pm(2)Ac4Pm8 cuboctahedra, and faces with eight equivalent Pm(1)Ac4Pm8 cuboctahedra. All Ac(1)-Pm(2) bond lengths are 3.77 Å. All Ac(1)-Pm(1) bond lengths are 3.73 Å. There are two inequivalent Pm sites. In the first Pm site, Pm(1) is bonded to four equivalent Ac(1), four equivalent Pm(1), and four equivalent Pm(2) atoms to form PmAc4Pm8 cuboctahedra that share corners with twelve equivalent Pm(1)Ac4Pm8 cuboctahedra, edges with eight equivalent Ac(1)Pm12 cuboctahedra, edges with eight equivalent Pm(1)Ac4Pm8 cuboctahedra, edges with eight equivalent Pm(2)Ac4Pm8 cuboctahedra, faces with four equivalent Ac(1)Pm12 cuboctahedra, faces with four equivalent Pm(2)Ac4Pm8 cuboctahedra, and faces with ten equivalent Pm(1)Ac4Pm8 cuboctahedra. All Pm(1)-Pm(1) bond lengths are 3.77 Å. All Pm(1)-Pm(2) bond lengths are 3.73 Å. In the second Pm site, Pm(2) is bonded to four equivalent Ac(1) and eight equivalent Pm(1) atoms to form PmAc4Pm8 cuboctahedra that share corners with four equivalent Pm(2)Ac4Pm8 cuboctahedra, corners with eight equivalent Ac(1)Pm12 cuboctahedra, edges with eight equivalent Pm(2)Ac4Pm8 cuboctahedra, edges with sixteen equivalent Pm(1)Ac4Pm8 cuboctahedra, faces with four equivalent Pm(2)Ac4Pm8 cuboctahedra, faces with six equivalent Ac(1)Pm12 cuboctahedra, and faces with eight equivalent Pm(1)Ac4Pm8 cuboctahedra.