ThCo3Al2 crystallizes in the orthorhombic Cmmm space group. Th(1) is bonded in a 6-coordinate geometry to four equivalent Co(2) and six equivalent Co(1) atoms. There are two inequivalent Co sites. In the first Co site, Co(2) is bonded in a 12-coordinate geometry to four equivalent Th(1), four equivalent Co(1), and four equivalent Al(1) atoms. In the second Co site, Co(1) is bonded in a 12-coordinate geometry to three equivalent Th(1), two equivalent Co(2), three equivalent Co(1), and four equivalent Al(1) atoms. Al(1) is bonded to two equivalent Co(2) and four equivalent Co(1) atoms to form a mixture of distorted face, corner, and edge-sharing AlCo6 cuboctahedra.
ThCo3Al2 crystallizes in the orthorhombic Cmmm space group. Th(1) is bonded in a 6-coordinate geometry to four equivalent Co(2) and six equivalent Co(1) atoms. All Th(1)-Co(2) bond lengths are 3.35 Å. There are two shorter (2.82 Å) and four longer (2.98 Å) Th(1)-Co(1) bond lengths. There are two inequivalent Co sites. In the first Co site, Co(2) is bonded in a 12-coordinate geometry to four equivalent Th(1), four equivalent Co(1), and four equivalent Al(1) atoms. All Co(2)-Co(1) bond lengths are 2.48 Å. All Co(2)-Al(1) bond lengths are 2.48 Å. In the second Co site, Co(1) is bonded in a 12-coordinate geometry to three equivalent Th(1), two equivalent Co(2), three equivalent Co(1), and four equivalent Al(1) atoms. There is one shorter (2.76 Å) and two longer (3.01 Å) Co(1)-Co(1) bond lengths. All Co(1)-Al(1) bond lengths are 2.55 Å. Al(1) is bonded to two equivalent Co(2) and four equivalent Co(1) atoms to form a mixture of distorted face, corner, and edge-sharing AlCo6 cuboctahedra.