Tm12(MnC3)5 crystallizes in the orthorhombic Amm2 space group. There are seven inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a rectangular see-saw-like geometry to two equivalent C(3) and two equivalent C(8) atoms. In the second Tm site, Tm(2) is bonded in a rectangular see-saw-like geometry to one C(7), one C(9), and two equivalent C(4) atoms. In the third Tm site, Tm(3) is bonded to one C(2), one C(4), one C(6), and two equivalent C(7) atoms to form a mixture of distorted edge and corner-sharing TmC5 square pyramids. In the fourth Tm site, Tm(4) is bonded to one C(2), one C(3), one C(5), and two equivalent C(8) atoms to form a mixture of distorted edge and corner-sharing TmC5 square pyramids. In the fifth Tm site, Tm(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 edge and corner-sharing TmC5 square pyramids. In the sixth Tm site, Tm(6) is bonded in a 8-coordinate geometry to two equivalent C(1), two equivalent C(5), two equivalent C(8), and two equivalent C(9) atoms. In the seventh Tm site, Tm(7) is bonded in a 8-coordinate geometry to one C(8), one C(9), two equivalent C(2), two equivalent C(6), and two equivalent C(7) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 3-coordinate geometry to one C(1) and two equivalent C(4) atoms. In the second Mn site, Mn(2) is bonded in a 3-coordinate geometry to one C(2), one C(3), and one C(4) atom. 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 two equivalent Tm(5), two equivalent Tm(6), one Mn(1), and one C(5) atom. In the second C site, C(2) is bonded in a 6-coordinate geometry to one Tm(3), one Tm(4), two equivalent Tm(7), one Mn(2), and one C(6) atom. In the third C site, C(3) is bonded to two equivalent Tm(1), two equivalent Tm(4), and two equivalent Mn(2) atoms to form CTm4Mn2 octahedra that share corners with two equivalent C(3)Tm4Mn2 octahedra, corners with two equivalent C(4)Tm4Mn2 octahedra, and edges with four equivalent C(8)Tm5Mn octahedra. The corner-sharing octahedral tilt angles range from 0-31°. In the fourth C site, C(4) is bonded to one Tm(3), one Tm(5), two equivalent Tm(2), one Mn(1), and one Mn(2) atom to form CTm4Mn2 octahedra that share  a cornercorner with one C(3)Tm4Mn2 octahedra, corners with three equivalent C(4)Tm4Mn2 octahedra, edges with two equivalent C(7)Tm5Mn octahedra, and edges with two equivalent C(9)Tm5Mn octahedra. The corner-sharing octahedral tilt angles range from 1-31°. In the fifth C site, C(5) is bonded in a 5-coordinate geometry to two equivalent Tm(4), two equivalent Tm(6), and one C(1) atom. In the sixth C site, C(6) is bonded in a 5-coordinate geometry to one Tm(3), one Tm(5), two equivalent Tm(7), and one C(2) atom. In the seventh C site, C(7) is bonded to one Tm(2), two equivalent Tm(3), two equivalent Tm(7), and one Mn(3) atom to form distorted CTm5Mn octahedra that share  a cornercorner with one C(8)Tm5Mn octahedra, corners with four equivalent C(7)Tm5Mn octahedra,  an edgeedge with one C(8)Tm5Mn octahedra, edges with two equivalent C(4)Tm4Mn2 octahedra, and edges with two equivalent C(9)Tm5Mn octahedra. The corner-sharing octahedral tilt angles range from 9-43°. In the eighth C site, C(8) is bonded to one Tm(1), one Tm(6), one Tm(7), two equivalent Tm(4), and one Mn(3) atom to form distorted CTm5Mn octahedra that share  a cornercorner with one C(7)Tm5Mn octahedra, corners with two equivalent C(8)Tm5Mn octahedra, corners with two equivalent C(9)Tm5Mn octahedra,  an edgeedge with one C(7)Tm5Mn octahedra,  an edgeedge with one C(8)Tm5Mn octahedra,  an edgeedge with one C(9)Tm5Mn octahedra, and edges with two equivalent C(3)Tm4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 9-43°. In the ninth C site, C(9) is bonded to one Tm(2), one Tm(6), one Tm(7), two equivalent Tm(5), and one Mn(3) atom to form distorted CTm5Mn octahedra that share corners with two equivalent C(8)Tm5Mn octahedra, corners with three equivalent C(9)Tm5Mn octahedra,  an edgeedge with one C(8)Tm5Mn octahedra, edges with two equivalent C(4)Tm4Mn2 octahedra, and edges with two equivalent C(7)Tm5Mn octahedra. The corner-sharing octahedral tilt angles range from 9-43°.
Tm12(MnC3)5 crystallizes in the orthorhombic Amm2 space group. There are seven inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a rectangular see-saw-like geometry to two equivalent C(3) and two equivalent C(8) atoms. Both Tm(1)-C(3) bond lengths are 2.47 Å. Both Tm(1)-C(8) bond lengths are 2.48 Å. In the second Tm site, Tm(2) is bonded in a rectangular see-saw-like geometry to one C(7), one C(9), and two equivalent C(4) atoms. The Tm(2)-C(7) bond length is 2.48 Å. The Tm(2)-C(9) bond length is 2.49 Å. Both Tm(2)-C(4) bond lengths are 2.47 Å. In the third Tm site, Tm(3) is bonded to one C(2), one C(4), one C(6), and two equivalent C(7) atoms to form a mixture of distorted edge and corner-sharing TmC5 square pyramids. The Tm(3)-C(2) bond length is 2.41 Å. The Tm(3)-C(4) bond length is 2.29 Å. The Tm(3)-C(6) bond length is 2.49 Å. Both Tm(3)-C(7) bond lengths are 2.48 Å. In the fourth Tm site, Tm(4) is bonded to one C(2), one C(3), one C(5), and two equivalent C(8) atoms to form a mixture of distorted edge and corner-sharing TmC5 square pyramids. The Tm(4)-C(2) bond length is 2.40 Å. The Tm(4)-C(3) bond length is 2.30 Å. The Tm(4)-C(5) bond length is 2.48 Å. Both Tm(4)-C(8) bond lengths are 2.48 Å. In the fifth Tm site, Tm(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 edge and corner-sharing TmC5 square pyramids. The Tm(5)-C(1) bond length is 2.40 Å. The Tm(5)-C(4) bond length is 2.29 Å. The Tm(5)-C(6) bond length is 2.49 Å. Both Tm(5)-C(9) bond lengths are 2.48 Å. In the sixth Tm site, Tm(6) is bonded in a 8-coordinate geometry to two equivalent C(1), two equivalent C(5), two equivalent C(8), and two equivalent C(9) atoms. Both Tm(6)-C(1) bond lengths are 2.69 Å. Both Tm(6)-C(5) bond lengths are 2.49 Å. Both Tm(6)-C(8) bond lengths are 2.63 Å. Both Tm(6)-C(9) bond lengths are 2.69 Å. In the seventh Tm site, Tm(7) is bonded in a 8-coordinate geometry to one C(8), one C(9), two equivalent C(2), two equivalent C(6), and two equivalent C(7) atoms. The Tm(7)-C(8) bond length is 2.69 Å. The Tm(7)-C(9) bond length is 2.65 Å. Both Tm(7)-C(2) bond lengths are 2.69 Å. Both Tm(7)-C(6) bond lengths are 2.49 Å. There is one shorter (2.64 Å) and one longer (2.69 Å) Tm(7)-C(7) bond length. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 3-coordinate geometry to one C(1) and two equivalent C(4) atoms. The Mn(1)-C(1) bond length is 1.80 Å. Both Mn(1)-C(4) bond lengths are 1.94 Å. In the second Mn site, Mn(2) is bonded in a 3-coordinate geometry to one C(2), one C(3), and one C(4) atom. The Mn(2)-C(2) bond length is 1.80 Å. The Mn(2)-C(3) bond length is 1.93 Å. The Mn(2)-C(4) bond length is 1.93 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 1.77 Å. The Mn(3)-C(9) bond length is 1.76 Å. There are nine inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to two equivalent Tm(5), two equivalent Tm(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 one Tm(3), one Tm(4), two equivalent Tm(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 two equivalent Tm(1), two equivalent Tm(4), and two equivalent Mn(2) atoms to form CTm4Mn2 octahedra that share corners with two equivalent C(3)Tm4Mn2 octahedra, corners with two equivalent C(4)Tm4Mn2 octahedra, and edges with four equivalent C(8)Tm5Mn octahedra. The corner-sharing octahedral tilt angles range from 0-31°. In the fourth C site, C(4) is bonded to one Tm(3), one Tm(5), two equivalent Tm(2), one Mn(1), and one Mn(2) atom to form CTm4Mn2 octahedra that share  a cornercorner with one C(3)Tm4Mn2 octahedra, corners with three equivalent C(4)Tm4Mn2 octahedra, edges with two equivalent C(7)Tm5Mn octahedra, and edges with two equivalent C(9)Tm5Mn octahedra. The corner-sharing octahedral tilt angles range from 1-31°. In the fifth C site, C(5) is bonded in a 5-coordinate geometry to two equivalent Tm(4), two equivalent Tm(6), and one C(1) atom. In the sixth C site, C(6) is bonded in a 5-coordinate geometry to one Tm(3), one Tm(5), two equivalent Tm(7), and one C(2) atom. In the seventh C site, C(7) is bonded to one Tm(2), two equivalent Tm(3), two equivalent Tm(7), and one Mn(3) atom to form distorted CTm5Mn octahedra that share  a cornercorner with one C(8)Tm5Mn octahedra, corners with four equivalent C(7)Tm5Mn octahedra,  an edgeedge with one C(8)Tm5Mn octahedra, edges with two equivalent C(4)Tm4Mn2 octahedra, and edges with two equivalent C(9)Tm5Mn octahedra. The corner-sharing octahedral tilt angles range from 9-43°. In the eighth C site, C(8) is bonded to one Tm(1), one Tm(6), one Tm(7), two equivalent Tm(4), and one Mn(3) atom to form distorted CTm5Mn octahedra that share  a cornercorner with one C(7)Tm5Mn octahedra, corners with two equivalent C(8)Tm5Mn octahedra, corners with two equivalent C(9)Tm5Mn octahedra,  an edgeedge with one C(7)Tm5Mn octahedra,  an edgeedge with one C(8)Tm5Mn octahedra,  an edgeedge with one C(9)Tm5Mn octahedra, and edges with two equivalent C(3)Tm4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 9-43°. In the ninth C site, C(9) is bonded to one Tm(2), one Tm(6), one Tm(7), two equivalent Tm(5), and one Mn(3) atom to form distorted CTm5Mn octahedra that share corners with two equivalent C(8)Tm5Mn octahedra, corners with three equivalent C(9)Tm5Mn octahedra,  an edgeedge with one C(8)Tm5Mn octahedra, edges with two equivalent C(4)Tm4Mn2 octahedra, and edges with two equivalent C(7)Tm5Mn octahedra. The corner-sharing octahedral tilt angles range from 9-43°.