Ta6Co16Si7 crystallizes in the cubic Fm-3m space group. Ta(1) is bonded in a 12-coordinate geometry to four equivalent Co(1), four equivalent Co(2), and four equivalent Si(1) atoms. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded in a 13-coordinate geometry to three equivalent Ta(1), three equivalent Co(1), three equivalent Co(2), one Si(2), and three equivalent Si(1) atoms. In the second Co site, Co(2) is bonded in a 12-coordinate geometry to three equivalent Ta(1), three equivalent Co(1), three equivalent Co(2), and three equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(2) is bonded in a body-centered cubic geometry to eight equivalent Co(1) atoms. In the second Si site, Si(1) is bonded to four equivalent Ta(1), four equivalent Co(1), and four equivalent Co(2) atoms to form a mixture of face and corner-sharing SiTa4Co8 cuboctahedra.
Ta6Co16Si7 crystallizes in the cubic Fm-3m space group. Ta(1) is bonded in a 12-coordinate geometry to four equivalent Co(1), four equivalent Co(2), and four equivalent Si(1) atoms. All Ta(1)-Co(1) bond lengths are 2.71 Å. All Ta(1)-Co(2) bond lengths are 2.64 Å. All Ta(1)-Si(1) bond lengths are 2.82 Å. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded in a 13-coordinate geometry to three equivalent Ta(1), three equivalent Co(1), three equivalent Co(2), one Si(2), and three equivalent Si(1) atoms. All Co(1)-Co(1) bond lengths are 2.62 Å. All Co(1)-Co(2) bond lengths are 2.49 Å. The Co(1)-Si(2) bond length is 2.27 Å. All Co(1)-Si(1) bond lengths are 2.44 Å. In the second Co site, Co(2) is bonded in a 12-coordinate geometry to three equivalent Ta(1), three equivalent Co(1), three equivalent Co(2), and three equivalent Si(1) atoms. All Co(2)-Co(2) bond lengths are 2.61 Å. All Co(2)-Si(1) bond lengths are 2.26 Å. There are two inequivalent Si sites. In the first Si site, Si(2) is bonded in a body-centered cubic geometry to eight equivalent Co(1) atoms. In the second Si site, Si(1) is bonded to four equivalent Ta(1), four equivalent Co(1), and four equivalent Co(2) atoms to form a mixture of face and corner-sharing SiTa4Co8 cuboctahedra.