AcPr3 is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. Ac(1) is bonded to four equivalent Pr(2) and eight equivalent Pr(1) atoms to form AcPr12 cuboctahedra that share corners with four equivalent Ac(1)Pr12 cuboctahedra, corners with eight equivalent Pr(2)Ac4Pr8 cuboctahedra, edges with eight equivalent Ac(1)Pr12 cuboctahedra, edges with sixteen equivalent Pr(1)Ac4Pr8 cuboctahedra, faces with four equivalent Ac(1)Pr12 cuboctahedra, faces with six equivalent Pr(2)Ac4Pr8 cuboctahedra, and faces with eight equivalent Pr(1)Ac4Pr8 cuboctahedra. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded to four equivalent Ac(1), four equivalent Pr(1), and four equivalent Pr(2) atoms to form PrAc4Pr8 cuboctahedra that share corners with twelve equivalent Pr(1)Ac4Pr8 cuboctahedra, edges with eight equivalent Ac(1)Pr12 cuboctahedra, edges with eight equivalent Pr(1)Ac4Pr8 cuboctahedra, edges with eight equivalent Pr(2)Ac4Pr8 cuboctahedra, faces with four equivalent Ac(1)Pr12 cuboctahedra, faces with four equivalent Pr(2)Ac4Pr8 cuboctahedra, and faces with ten equivalent Pr(1)Ac4Pr8 cuboctahedra. In the second Pr site, Pr(2) is bonded to four equivalent Ac(1) and eight equivalent Pr(1) atoms to form PrAc4Pr8 cuboctahedra that share corners with four equivalent Pr(2)Ac4Pr8 cuboctahedra, corners with eight equivalent Ac(1)Pr12 cuboctahedra, edges with eight equivalent Pr(2)Ac4Pr8 cuboctahedra, edges with sixteen equivalent Pr(1)Ac4Pr8 cuboctahedra, faces with four equivalent Pr(2)Ac4Pr8 cuboctahedra, faces with six equivalent Ac(1)Pr12 cuboctahedra, and faces with eight equivalent Pr(1)Ac4Pr8 cuboctahedra.
AcPr3 is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. Ac(1) is bonded to four equivalent Pr(2) and eight equivalent Pr(1) atoms to form AcPr12 cuboctahedra that share corners with four equivalent Ac(1)Pr12 cuboctahedra, corners with eight equivalent Pr(2)Ac4Pr8 cuboctahedra, edges with eight equivalent Ac(1)Pr12 cuboctahedra, edges with sixteen equivalent Pr(1)Ac4Pr8 cuboctahedra, faces with four equivalent Ac(1)Pr12 cuboctahedra, faces with six equivalent Pr(2)Ac4Pr8 cuboctahedra, and faces with eight equivalent Pr(1)Ac4Pr8 cuboctahedra. All Ac(1)-Pr(2) bond lengths are 3.80 Å. All Ac(1)-Pr(1) bond lengths are 3.80 Å. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded to four equivalent Ac(1), four equivalent Pr(1), and four equivalent Pr(2) atoms to form PrAc4Pr8 cuboctahedra that share corners with twelve equivalent Pr(1)Ac4Pr8 cuboctahedra, edges with eight equivalent Ac(1)Pr12 cuboctahedra, edges with eight equivalent Pr(1)Ac4Pr8 cuboctahedra, edges with eight equivalent Pr(2)Ac4Pr8 cuboctahedra, faces with four equivalent Ac(1)Pr12 cuboctahedra, faces with four equivalent Pr(2)Ac4Pr8 cuboctahedra, and faces with ten equivalent Pr(1)Ac4Pr8 cuboctahedra. All Pr(1)-Pr(1) bond lengths are 3.80 Å. All Pr(1)-Pr(2) bond lengths are 3.80 Å. In the second Pr site, Pr(2) is bonded to four equivalent Ac(1) and eight equivalent Pr(1) atoms to form PrAc4Pr8 cuboctahedra that share corners with four equivalent Pr(2)Ac4Pr8 cuboctahedra, corners with eight equivalent Ac(1)Pr12 cuboctahedra, edges with eight equivalent Pr(2)Ac4Pr8 cuboctahedra, edges with sixteen equivalent Pr(1)Ac4Pr8 cuboctahedra, faces with four equivalent Pr(2)Ac4Pr8 cuboctahedra, faces with six equivalent Ac(1)Pr12 cuboctahedra, and faces with eight equivalent Pr(1)Ac4Pr8 cuboctahedra.