PuAl3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Pu sites. In the first Pu site, Pu(1) is bonded to six equivalent Al(1) and six Al(2,2) atoms to form PuAl12 cuboctahedra that share corners with six equivalent Pu(1)Al12 cuboctahedra; corners with six equivalent Pu(2)Al12 cuboctahedra; edges with eighteen Al(2,2)Pu4Al8 cuboctahedra; faces with six equivalent Pu(2)Al12 cuboctahedra; and faces with six Al(2,2)Pu4Al8 cuboctahedra. In the second Pu site, Pu(2) is bonded to three equivalent Al(1) and nine Al(2,2) atoms to form PuAl12 cuboctahedra that share corners with three equivalent Pu(1)Al12 cuboctahedra; corners with six equivalent Pu(2)Al12 cuboctahedra; corners with six Al(2,2)Pu4Al8 cuboctahedra; edges with twelve Al(2,2)Pu4Al8 cuboctahedra; faces with three equivalent Pu(1)Al12 cuboctahedra; faces with four equivalent Pu(2)Al12 cuboctahedra; and faces with nine Al(2,2)Pu4Al8 cuboctahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded in a 12-coordinate geometry to two equivalent Pu(1), two equivalent Pu(2), four equivalent Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(2) is bonded to one Pu(1), three equivalent Pu(2), two equivalent Al(1), and six equivalent Al(2) atoms to form distorted AlPu4Al8 cuboctahedra that share corners with two equivalent Pu(2)Al12 cuboctahedra; corners with ten equivalent Al(2)Pu4Al8 cuboctahedra; edges with three equivalent Pu(1)Al12 cuboctahedra; edges with four equivalent Pu(2)Al12 cuboctahedra; edges with eight equivalent Al(2)Pu4Al8 cuboctahedra;  a faceface with one Pu(1)Al12 cuboctahedra; faces with three equivalent Pu(2)Al12 cuboctahedra; and faces with ten Al(2,2)Pu4Al8 cuboctahedra. In the third Al site, Al(2) is bonded to one Pu(1), three equivalent Pu(2), two equivalent Al(1), and six equivalent Al(2) atoms to form distorted AlPu4Al8 cuboctahedra that share corners with two equivalent Pu(2)Al12 cuboctahedra; corners with ten Al(2,2)Pu4Al8 cuboctahedra; edges with three equivalent Pu(1)Al12 cuboctahedra; edges with four equivalent Pu(2)Al12 cuboctahedra; edges with eight equivalent Al(2)Pu4Al8 cuboctahedra;  a faceface with one Pu(1)Al12 cuboctahedra; faces with three equivalent Pu(2)Al12 cuboctahedra; and faces with ten Al(2,2)Pu4Al8 cuboctahedra.
PuAl3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Pu sites. In the first Pu site, Pu(1) is bonded to six equivalent Al(1) and six Al(2,2) atoms to form PuAl12 cuboctahedra that share corners with six equivalent Pu(1)Al12 cuboctahedra; corners with six equivalent Pu(2)Al12 cuboctahedra; edges with eighteen Al(2,2)Pu4Al8 cuboctahedra; faces with six equivalent Pu(2)Al12 cuboctahedra; and faces with six Al(2,2)Pu4Al8 cuboctahedra. All Pu(1)-Al(1) bond lengths are 3.00 Å. All Pu(1)-Al(2,2) bond lengths are 2.98 Å. In the second Pu site, Pu(2) is bonded to three equivalent Al(1) and nine Al(2,2) atoms to form PuAl12 cuboctahedra that share corners with three equivalent Pu(1)Al12 cuboctahedra; corners with six equivalent Pu(2)Al12 cuboctahedra; corners with six Al(2,2)Pu4Al8 cuboctahedra; edges with twelve Al(2,2)Pu4Al8 cuboctahedra; faces with three equivalent Pu(1)Al12 cuboctahedra; faces with four equivalent Pu(2)Al12 cuboctahedra; and faces with nine Al(2,2)Pu4Al8 cuboctahedra. All Pu(2)-Al(1) bond lengths are 2.99 Å. There are three shorter (2.97 Å) and six longer (2.99 Å) Pu(2)-Al(2,2) bond lengths. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded in a 12-coordinate geometry to two equivalent Pu(1), two equivalent Pu(2), four equivalent Al(1), and four equivalent Al(2) atoms. There are two shorter (2.86 Å) and two longer (3.13 Å) Al(1)-Al(1) bond lengths. All Al(1)-Al(2) bond lengths are 2.94 Å. In the second Al site, Al(2) is bonded to one Pu(1), three equivalent Pu(2), two equivalent Al(1), and six equivalent Al(2) atoms to form distorted AlPu4Al8 cuboctahedra that share corners with two equivalent Pu(2)Al12 cuboctahedra; corners with ten equivalent Al(2)Pu4Al8 cuboctahedra; edges with three equivalent Pu(1)Al12 cuboctahedra; edges with four equivalent Pu(2)Al12 cuboctahedra; edges with eight equivalent Al(2)Pu4Al8 cuboctahedra;  a faceface with one Pu(1)Al12 cuboctahedra; faces with three equivalent Pu(2)Al12 cuboctahedra; and faces with ten Al(2,2)Pu4Al8 cuboctahedra. There are four shorter (2.96 Å) and two longer (3.03 Å) Al(2)-Al(2) bond lengths. In the third Al site, Al(2) is bonded to one Pu(1), three equivalent Pu(2), two equivalent Al(1), and six equivalent Al(2) atoms to form distorted AlPu4Al8 cuboctahedra that share corners with two equivalent Pu(2)Al12 cuboctahedra; corners with ten Al(2,2)Pu4Al8 cuboctahedra; edges with three equivalent Pu(1)Al12 cuboctahedra; edges with four equivalent Pu(2)Al12 cuboctahedra; edges with eight equivalent Al(2)Pu4Al8 cuboctahedra;  a faceface with one Pu(1)Al12 cuboctahedra; faces with three equivalent Pu(2)Al12 cuboctahedra; and faces with ten Al(2,2)Pu4Al8 cuboctahedra. Both Al(2)-Al(1) bond lengths are 2.94 Å. There are four shorter (2.96 Å) and two longer (3.03 Å) Al(2)-Al(2) bond lengths.