Co5Ge7 crystallizes in the tetragonal I4mm space group. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded in a 5-coordinate geometry to one Ge(1) and four equivalent Ge(3) atoms. In the second Co site, Co(2) is bonded in a 4-coordinate geometry to two equivalent Ge(2) and four equivalent Ge(3) atoms. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a single-bond geometry to one Co(1) and four equivalent Ge(3) atoms. In the second Ge site, Ge(2) is bonded in a 10-coordinate geometry to four equivalent Co(2), two equivalent Ge(2), and four equivalent Ge(3) atoms. In the third Ge site, Ge(3) is bonded in a 10-coordinate geometry to one Co(1), four equivalent Co(2), one Ge(1), two equivalent Ge(2), and two equivalent Ge(3) atoms.
Co5Ge7 crystallizes in the tetragonal I4mm space group. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded in a 5-coordinate geometry to one Ge(1) and four equivalent Ge(3) atoms. The Co(1)-Ge(1) bond length is 2.23 Å. All Co(1)-Ge(3) bond lengths are 2.37 Å. In the second Co site, Co(2) is bonded in a 4-coordinate geometry to two equivalent Ge(2) and four equivalent Ge(3) atoms. Both Co(2)-Ge(2) bond lengths are 2.84 Å. There are two shorter (2.46 Å) and two longer (2.53 Å) Co(2)-Ge(3) bond lengths. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a single-bond geometry to one Co(1) and four equivalent Ge(3) atoms. All Ge(1)-Ge(3) bond lengths are 2.95 Å. In the second Ge site, Ge(2) is bonded in a 10-coordinate geometry to four equivalent Co(2), two equivalent Ge(2), and four equivalent Ge(3) atoms. Both Ge(2)-Ge(2) bond lengths are 2.93 Å. There are two shorter (2.51 Å) and two longer (2.56 Å) Ge(2)-Ge(3) bond lengths. In the third Ge site, Ge(3) is bonded in a 10-coordinate geometry to one Co(1), four equivalent Co(2), one Ge(1), two equivalent Ge(2), and two equivalent Ge(3) atoms. Both Ge(3)-Ge(3) bond lengths are 2.72 Å.