Tb12(MnC3)5 crystallizes in the orthorhombic Amm2 space group. There are seven inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a rectangular see-saw-like geometry to one C(7), one C(8), and two equivalent C(3) atoms. In the second Tb site, Tb(2) is bonded in a rectangular see-saw-like geometry to two equivalent C(4) and two equivalent C(9) atoms. In the third Tb site, Tb(3) is bonded to one C(2), one C(3), one C(5), and two equivalent C(7) atoms to form a mixture of distorted corner and edge-sharing TbC5 square pyramids. In the fourth Tb site, Tb(4) is bonded to one C(1), one C(3), one C(5), and two equivalent C(8) atoms to form a mixture of distorted corner and edge-sharing TbC5 square pyramids. In the fifth Tb site, Tb(5) is bonded to one C(1), one C(4), one C(6), and two equivalent C(9) atoms to form a mixture of distorted corner and edge-sharing TbC5 square pyramids. In the sixth Tb site, Tb(6) is bonded in a 8-coordinate geometry to one C(7), one C(9), two equivalent C(1), two equivalent C(5), and two equivalent C(8) atoms. In the seventh Tb site, Tb(7) is bonded in a 8-coordinate geometry to two equivalent C(2), two equivalent C(6), two equivalent C(7), and two equivalent C(9) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a distorted trigonal non-coplanar geometry to one C(1), one C(3), and one C(4) atom. In the second Mn site, Mn(2) is bonded in a 3-coordinate geometry to one C(2) and two equivalent C(3) atoms. In the third Mn site, Mn(3) is bonded in a trigonal planar geometry to one C(7), one C(8), and one C(9) atom. There are nine inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to one Tb(4), one Tb(5), two equivalent Tb(6), one Mn(1), and one C(5) atom. In the second C site, C(2) is bonded in a 6-coordinate geometry to two equivalent Tb(3), two equivalent Tb(7), one Mn(2), and one C(6) atom. In the third C site, C(3) is bonded to one Tb(3), one Tb(4), two equivalent Tb(1), one Mn(1), and one Mn(2) atom to form CTb4Mn2 octahedra that share  a cornercorner with one C(4)Tb4Mn2 octahedra, corners with three equivalent C(3)Tb4Mn2 octahedra, edges with two equivalent C(7)Tb5Mn octahedra, and edges with two equivalent C(8)Tb5Mn octahedra. The corner-sharing octahedral tilt angles range from 1-33°. In the fourth C site, C(4) is bonded to two equivalent Tb(2), two equivalent Tb(5), and two equivalent Mn(1) atoms to form CTb4Mn2 octahedra that share corners with two equivalent C(3)Tb4Mn2 octahedra, corners with two equivalent C(4)Tb4Mn2 octahedra, and edges with four equivalent C(9)Tb5Mn octahedra. The corner-sharing octahedral tilt angles range from 3-33°. In the fifth C site, C(5) is bonded in a 5-coordinate geometry to one Tb(3), one Tb(4), two equivalent Tb(6), and one C(1) atom. In the sixth C site, C(6) is bonded in a 5-coordinate geometry to two equivalent Tb(5), two equivalent Tb(7), and one C(2) atom. In the seventh C site, C(7) is bonded to one Tb(1), one Tb(6), one Tb(7), two equivalent Tb(3), and one Mn(3) atom to form distorted CTb5Mn octahedra that share corners with two equivalent C(9)Tb5Mn octahedra, corners with three equivalent C(7)Tb5Mn octahedra,  an edgeedge with one C(9)Tb5Mn octahedra, edges with two equivalent C(3)Tb4Mn2 octahedra, and edges with two equivalent C(8)Tb5Mn octahedra. The corner-sharing octahedral tilt angles range from 10-41°. In the eighth C site, C(8) is bonded to one Tb(1), two equivalent Tb(4), two equivalent Tb(6), and one Mn(3) atom to form distorted CTb5Mn octahedra that share  a cornercorner with one C(9)Tb5Mn octahedra, corners with four equivalent C(8)Tb5Mn octahedra,  an edgeedge with one C(9)Tb5Mn octahedra, edges with two equivalent C(3)Tb4Mn2 octahedra, and edges with two equivalent C(7)Tb5Mn octahedra. The corner-sharing octahedral tilt angles range from 9-40°. In the ninth C site, C(9) is bonded to one Tb(2), one Tb(6), one Tb(7), two equivalent Tb(5), and one Mn(3) atom to form distorted CTb5Mn octahedra that share  a cornercorner with one C(8)Tb5Mn octahedra, corners with two equivalent C(7)Tb5Mn octahedra, corners with two equivalent C(9)Tb5Mn octahedra,  an edgeedge with one C(7)Tb5Mn octahedra,  an edgeedge with one C(8)Tb5Mn octahedra,  an edgeedge with one C(9)Tb5Mn octahedra, and edges with two equivalent C(4)Tb4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 10-40°.
Tb12(MnC3)5 crystallizes in the orthorhombic Amm2 space group. There are seven inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a rectangular see-saw-like geometry to one C(7), one C(8), and two equivalent C(3) atoms. The Tb(1)-C(7) bond length is 2.56 Å. The Tb(1)-C(8) bond length is 2.55 Å. Both Tb(1)-C(3) bond lengths are 2.54 Å. In the second Tb site, Tb(2) is bonded in a rectangular see-saw-like geometry to two equivalent C(4) and two equivalent C(9) atoms. Both Tb(2)-C(4) bond lengths are 2.54 Å. Both Tb(2)-C(9) bond lengths are 2.53 Å. In the third Tb site, Tb(3) is bonded to one C(2), one C(3), one C(5), and two equivalent C(7) atoms to form a mixture of distorted corner and edge-sharing TbC5 square pyramids. The Tb(3)-C(2) bond length is 2.44 Å. The Tb(3)-C(3) bond length is 2.36 Å. The Tb(3)-C(5) bond length is 2.56 Å. Both Tb(3)-C(7) bond lengths are 2.55 Å. In the fourth Tb site, Tb(4) is bonded to one C(1), one C(3), one C(5), and two equivalent C(8) atoms to form a mixture of distorted corner and edge-sharing TbC5 square pyramids. The Tb(4)-C(1) bond length is 2.45 Å. The Tb(4)-C(3) bond length is 2.36 Å. The Tb(4)-C(5) bond length is 2.55 Å. Both Tb(4)-C(8) bond lengths are 2.55 Å. In the fifth Tb site, Tb(5) is bonded to one C(1), one C(4), one C(6), and two equivalent C(9) atoms to form a mixture of distorted corner and edge-sharing TbC5 square pyramids. The Tb(5)-C(1) bond length is 2.45 Å. The Tb(5)-C(4) bond length is 2.38 Å. The Tb(5)-C(6) bond length is 2.56 Å. Both Tb(5)-C(9) bond lengths are 2.55 Å. In the sixth Tb site, Tb(6) is bonded in a 8-coordinate geometry to one C(7), one C(9), two equivalent C(1), two equivalent C(5), and two equivalent C(8) atoms. The Tb(6)-C(7) bond length is 2.70 Å. The Tb(6)-C(9) bond length is 2.73 Å. Both Tb(6)-C(1) bond lengths are 2.75 Å. Both Tb(6)-C(5) bond lengths are 2.56 Å. There is one shorter (2.69 Å) and one longer (2.74 Å) Tb(6)-C(8) bond length. In the seventh Tb site, Tb(7) is bonded in a 8-coordinate geometry to two equivalent C(2), two equivalent C(6), two equivalent C(7), and two equivalent C(9) atoms. Both Tb(7)-C(2) bond lengths are 2.76 Å. Both Tb(7)-C(6) bond lengths are 2.55 Å. Both Tb(7)-C(7) bond lengths are 2.75 Å. Both Tb(7)-C(9) bond lengths are 2.67 Å. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a distorted trigonal non-coplanar geometry to one C(1), one C(3), and one C(4) atom. The Mn(1)-C(1) bond length is 1.81 Å. The Mn(1)-C(3) bond length is 1.94 Å. The Mn(1)-C(4) bond length is 1.93 Å. In the second Mn site, Mn(2) is bonded in a 3-coordinate geometry to one C(2) and two equivalent C(3) atoms. The Mn(2)-C(2) bond length is 1.81 Å. Both Mn(2)-C(3) bond lengths are 1.95 Å. In the third Mn site, Mn(3) is bonded in a trigonal planar geometry to one C(7), one C(8), and one C(9) atom. The Mn(3)-C(7) bond length is 1.76 Å. The Mn(3)-C(8) bond length is 1.76 Å. The Mn(3)-C(9) bond length is 1.77 Å. There are nine inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to one Tb(4), one Tb(5), two equivalent Tb(6), one Mn(1), and one C(5) atom. The C(1)-C(5) bond length is 1.35 Å. In the second C site, C(2) is bonded in a 6-coordinate geometry to two equivalent Tb(3), two equivalent Tb(7), one Mn(2), and one C(6) atom. The C(2)-C(6) bond length is 1.35 Å. In the third C site, C(3) is bonded to one Tb(3), one Tb(4), two equivalent Tb(1), one Mn(1), and one Mn(2) atom to form CTb4Mn2 octahedra that share  a cornercorner with one C(4)Tb4Mn2 octahedra, corners with three equivalent C(3)Tb4Mn2 octahedra, edges with two equivalent C(7)Tb5Mn octahedra, and edges with two equivalent C(8)Tb5Mn octahedra. The corner-sharing octahedral tilt angles range from 1-33°. In the fourth C site, C(4) is bonded to two equivalent Tb(2), two equivalent Tb(5), and two equivalent Mn(1) atoms to form CTb4Mn2 octahedra that share corners with two equivalent C(3)Tb4Mn2 octahedra, corners with two equivalent C(4)Tb4Mn2 octahedra, and edges with four equivalent C(9)Tb5Mn octahedra. The corner-sharing octahedral tilt angles range from 3-33°. In the fifth C site, C(5) is bonded in a 5-coordinate geometry to one Tb(3), one Tb(4), two equivalent Tb(6), and one C(1) atom. In the sixth C site, C(6) is bonded in a 5-coordinate geometry to two equivalent Tb(5), two equivalent Tb(7), and one C(2) atom. In the seventh C site, C(7) is bonded to one Tb(1), one Tb(6), one Tb(7), two equivalent Tb(3), and one Mn(3) atom to form distorted CTb5Mn octahedra that share corners with two equivalent C(9)Tb5Mn octahedra, corners with three equivalent C(7)Tb5Mn octahedra,  an edgeedge with one C(9)Tb5Mn octahedra, edges with two equivalent C(3)Tb4Mn2 octahedra, and edges with two equivalent C(8)Tb5Mn octahedra. The corner-sharing octahedral tilt angles range from 10-41°. In the eighth C site, C(8) is bonded to one Tb(1), two equivalent Tb(4), two equivalent Tb(6), and one Mn(3) atom to form distorted CTb5Mn octahedra that share  a cornercorner with one C(9)Tb5Mn octahedra, corners with four equivalent C(8)Tb5Mn octahedra,  an edgeedge with one C(9)Tb5Mn octahedra, edges with two equivalent C(3)Tb4Mn2 octahedra, and edges with two equivalent C(7)Tb5Mn octahedra. The corner-sharing octahedral tilt angles range from 9-40°. In the ninth C site, C(9) is bonded to one Tb(2), one Tb(6), one Tb(7), two equivalent Tb(5), and one Mn(3) atom to form distorted CTb5Mn octahedra that share  a cornercorner with one C(8)Tb5Mn octahedra, corners with two equivalent C(7)Tb5Mn octahedra, corners with two equivalent C(9)Tb5Mn octahedra,  an edgeedge with one C(7)Tb5Mn octahedra,  an edgeedge with one C(8)Tb5Mn octahedra,  an edgeedge with one C(9)Tb5Mn octahedra, and edges with two equivalent C(4)Tb4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 10-40°.