Tb12Co7 crystallizes in the monoclinic P2_1/c space group. There are six inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 5-coordinate geometry to one Co(1), one Co(2), one Co(3), and two equivalent Co(4) atoms. In the second Tb site, Tb(2) is bonded in a 4-coordinate geometry to one Co(2), one Co(4), and two equivalent Co(3) atoms. In the third Tb site, Tb(3) is bonded in a 4-coordinate geometry to one Co(2), one Co(4), and two equivalent Co(3) atoms. In the fourth Tb site, Tb(4) is bonded in a 5-coordinate geometry to one Co(1), one Co(2), one Co(3), and two equivalent Co(4) atoms. In the fifth Tb site, Tb(5) is bonded to one Co(1), one Co(2), one Co(3), and one Co(4) atom to form distorted corner-sharing TbCo4 tetrahedra. In the sixth Tb site, Tb(6) is bonded in a 5-coordinate geometry to one Co(1), one Co(3), one Co(4), and two equivalent Co(2) atoms. There are four inequivalent Co sites. In the first Co site, Co(4) is bonded in a 9-coordinate geometry to one Tb(2), one Tb(3), one Tb(5), one Tb(6), two equivalent Tb(1), two equivalent Tb(4), and one Co(2) atom. In the second Co site, Co(1) is bonded in a body-centered cubic geometry to two equivalent Tb(1), two equivalent Tb(4), two equivalent Tb(5), and two equivalent Tb(6) atoms. In the third Co site, Co(2) is bonded in a 8-coordinate geometry to one Tb(1), one Tb(2), one Tb(3), one Tb(4), one Tb(5), two equivalent Tb(6), and one Co(4) atom. In the fourth Co site, Co(3) is bonded in a 8-coordinate geometry to one Tb(1), one Tb(4), one Tb(5), one Tb(6), two equivalent Tb(2), and two equivalent Tb(3) atoms.
Tb12Co7 crystallizes in the monoclinic P2_1/c space group. There are six inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 5-coordinate geometry to one Co(1), one Co(2), one Co(3), and two equivalent Co(4) atoms. The Tb(1)-Co(1) bond length is 3.06 Å. The Tb(1)-Co(2) bond length is 3.10 Å. The Tb(1)-Co(3) bond length is 2.87 Å. There is one shorter (3.00 Å) and one longer (3.08 Å) Tb(1)-Co(4) bond length. In the second Tb site, Tb(2) is bonded in a 4-coordinate geometry to one Co(2), one Co(4), and two equivalent Co(3) atoms. The Tb(2)-Co(2) bond length is 2.79 Å. The Tb(2)-Co(4) bond length is 2.75 Å. There is one shorter (2.93 Å) and one longer (3.01 Å) Tb(2)-Co(3) bond length. In the third Tb site, Tb(3) is bonded in a 4-coordinate geometry to one Co(2), one Co(4), and two equivalent Co(3) atoms. The Tb(3)-Co(2) bond length is 3.07 Å. The Tb(3)-Co(4) bond length is 2.84 Å. There is one shorter (2.79 Å) and one longer (2.80 Å) Tb(3)-Co(3) bond length. In the fourth Tb site, Tb(4) is bonded in a 5-coordinate geometry to one Co(1), one Co(2), one Co(3), and two equivalent Co(4) atoms. The Tb(4)-Co(1) bond length is 3.00 Å. The Tb(4)-Co(2) bond length is 2.98 Å. The Tb(4)-Co(3) bond length is 2.86 Å. There is one shorter (2.83 Å) and one longer (3.41 Å) Tb(4)-Co(4) bond length. In the fifth Tb site, Tb(5) is bonded to one Co(1), one Co(2), one Co(3), and one Co(4) atom to form distorted corner-sharing TbCo4 tetrahedra. The Tb(5)-Co(1) bond length is 2.92 Å. The Tb(5)-Co(2) bond length is 2.75 Å. The Tb(5)-Co(3) bond length is 2.84 Å. The Tb(5)-Co(4) bond length is 3.01 Å. In the sixth Tb site, Tb(6) is bonded in a 5-coordinate geometry to one Co(1), one Co(3), one Co(4), and two equivalent Co(2) atoms. The Tb(6)-Co(1) bond length is 2.89 Å. The Tb(6)-Co(3) bond length is 2.75 Å. The Tb(6)-Co(4) bond length is 2.97 Å. There is one shorter (2.80 Å) and one longer (3.19 Å) Tb(6)-Co(2) bond length. There are four inequivalent Co sites. In the first Co site, Co(4) is bonded in a 9-coordinate geometry to one Tb(2), one Tb(3), one Tb(5), one Tb(6), two equivalent Tb(1), two equivalent Tb(4), and one Co(2) atom. The Co(4)-Co(2) bond length is 2.29 Å. In the second Co site, Co(1) is bonded in a body-centered cubic geometry to two equivalent Tb(1), two equivalent Tb(4), two equivalent Tb(5), and two equivalent Tb(6) atoms. In the third Co site, Co(2) is bonded in a 8-coordinate geometry to one Tb(1), one Tb(2), one Tb(3), one Tb(4), one Tb(5), two equivalent Tb(6), and one Co(4) atom. In the fourth Co site, Co(3) is bonded in a 8-coordinate geometry to one Tb(1), one Tb(4), one Tb(5), one Tb(6), two equivalent Tb(2), and two equivalent Tb(3) atoms.