Ti4Co4Ge7 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a 7-coordinate geometry to two equivalent Ge(2), two equivalent Ge(4), and three equivalent Ge(1) atoms. In the second Ti site, Ti(2) is bonded to one Ge(3), two equivalent Ge(1), two equivalent Ge(2), and two equivalent Ge(4) atoms to form a mixture of distorted corner, edge, and face-sharing TiGe7 pentagonal bipyramids. Co(1) is bonded in a 6-coordinate geometry to two equivalent Ge(1), two equivalent Ge(2), and two equivalent Ge(3) atoms. There are four inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to two equivalent Ti(2), three equivalent Ti(1), and four equivalent Co(1) atoms. In the second Ge site, Ge(2) is bonded in a 8-coordinate geometry to two equivalent Ti(1), two equivalent Ti(2), and four equivalent Co(1) atoms. In the third Ge site, Ge(3) is bonded in a 6-coordinate geometry to one Ti(2), four equivalent Co(1), and one Ge(3) atom. In the fourth Ge site, Ge(4) is bonded in a 10-coordinate geometry to four equivalent Ti(1), four equivalent Ti(2), and two equivalent Ge(4) atoms.
Ti4Co4Ge7 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a 7-coordinate geometry to two equivalent Ge(2), two equivalent Ge(4), and three equivalent Ge(1) atoms. Both Ti(1)-Ge(2) bond lengths are 2.58 Å. Both Ti(1)-Ge(4) bond lengths are 2.79 Å. There are two shorter (2.81 Å) and one longer (2.93 Å) Ti(1)-Ge(1) bond length. In the second Ti site, Ti(2) is bonded to one Ge(3), two equivalent Ge(1), two equivalent Ge(2), and two equivalent Ge(4) atoms to form a mixture of distorted corner, edge, and face-sharing TiGe7 pentagonal bipyramids. The Ti(2)-Ge(3) bond length is 2.72 Å. Both Ti(2)-Ge(1) bond lengths are 2.60 Å. Both Ti(2)-Ge(2) bond lengths are 2.81 Å. Both Ti(2)-Ge(4) bond lengths are 2.78 Å. Co(1) is bonded in a 6-coordinate geometry to two equivalent Ge(1), two equivalent Ge(2), and two equivalent Ge(3) atoms. Both Co(1)-Ge(1) bond lengths are 2.38 Å. Both Co(1)-Ge(2) bond lengths are 2.47 Å. Both Co(1)-Ge(3) bond lengths are 2.42 Å. There are four inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to two equivalent Ti(2), three equivalent Ti(1), and four equivalent Co(1) atoms. In the second Ge site, Ge(2) is bonded in a 8-coordinate geometry to two equivalent Ti(1), two equivalent Ti(2), and four equivalent Co(1) atoms. In the third Ge site, Ge(3) is bonded in a 6-coordinate geometry to one Ti(2), four equivalent Co(1), and one Ge(3) atom. The Ge(3)-Ge(3) bond length is 2.49 Å. In the fourth Ge site, Ge(4) is bonded in a 10-coordinate geometry to four equivalent Ti(1), four equivalent Ti(2), and two equivalent Ge(4) atoms. There is one shorter (2.54 Å) and one longer (2.55 Å) Ge(4)-Ge(4) bond length.