Sm12(OsC3)5 crystallizes in the hexagonal P-62m space group. There are three inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a rectangular see-saw-like geometry to two equivalent C(2) and two equivalent C(4) atoms. In the second Sm site, Sm(2) is bonded to one C(1), one C(2), one C(3), and two equivalent C(4) atoms to form a mixture of distorted edge and corner-sharing SmC5 square pyramids. In the third Sm site, Sm(3) is bonded in a 8-coordinate geometry to two equivalent C(1), two equivalent C(3), and four equivalent C(4) atoms. There are two inequivalent Os sites. In the first Os site, Os(1) is bonded in a distorted trigonal planar geometry to one C(1) and two equivalent C(2) atoms. In the second Os site, Os(2) is bonded in a trigonal planar geometry to three equivalent C(4) atoms. There are four inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to two equivalent Sm(2), two equivalent Sm(3), one Os(1), and one C(3) atom. In the second C site, C(2) is bonded to two equivalent Sm(1), two equivalent Sm(2), and two equivalent Os(1) atoms to form CSm4Os2 octahedra that share corners with four equivalent C(2)Sm4Os2 octahedra and edges with four equivalent C(4)Sm5Os octahedra. The corner-sharing octahedral tilt angles range from 2-37°. In the third C site, C(3) is bonded in a 5-coordinate geometry to two equivalent Sm(2), two equivalent Sm(3), and one C(1) atom. In the fourth C site, C(4) is bonded to one Sm(1), two equivalent Sm(2), two equivalent Sm(3), and one Os(2) atom to form CSm5Os octahedra that share corners with five equivalent C(4)Sm5Os octahedra, edges with two equivalent C(2)Sm4Os2 octahedra, and edges with three equivalent C(4)Sm5Os octahedra. The corner-sharing octahedral tilt angles range from 7-45°.
Sm12(OsC3)5 crystallizes in the hexagonal P-62m space group. There are three inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a rectangular see-saw-like geometry to two equivalent C(2) and two equivalent C(4) atoms. Both Sm(1)-C(2) bond lengths are 2.62 Å. Both Sm(1)-C(4) bond lengths are 2.56 Å. In the second Sm site, Sm(2) is bonded to one C(1), one C(2), one C(3), and two equivalent C(4) atoms to form a mixture of distorted edge and corner-sharing SmC5 square pyramids. The Sm(2)-C(1) bond length is 2.57 Å. The Sm(2)-C(2) bond length is 2.47 Å. The Sm(2)-C(3) bond length is 2.61 Å. Both Sm(2)-C(4) bond lengths are 2.62 Å. In the third Sm site, Sm(3) is bonded in a 8-coordinate geometry to two equivalent C(1), two equivalent C(3), and four equivalent C(4) atoms. Both Sm(3)-C(1) bond lengths are 2.83 Å. Both Sm(3)-C(3) bond lengths are 2.63 Å. There are two shorter (2.71 Å) and two longer (2.91 Å) Sm(3)-C(4) bond lengths. There are two inequivalent Os sites. In the first Os site, Os(1) is bonded in a distorted trigonal planar geometry to one C(1) and two equivalent C(2) atoms. The Os(1)-C(1) bond length is 1.87 Å. Both Os(1)-C(2) bond lengths are 2.01 Å. In the second Os site, Os(2) is bonded in a trigonal planar geometry to three equivalent C(4) atoms. All Os(2)-C(4) bond lengths are 1.91 Å. There are four inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to two equivalent Sm(2), two equivalent Sm(3), one Os(1), and one C(3) atom. The C(1)-C(3) bond length is 1.33 Å. In the second C site, C(2) is bonded to two equivalent Sm(1), two equivalent Sm(2), and two equivalent Os(1) atoms to form CSm4Os2 octahedra that share corners with four equivalent C(2)Sm4Os2 octahedra and edges with four equivalent C(4)Sm5Os octahedra. The corner-sharing octahedral tilt angles range from 2-37°. In the third C site, C(3) is bonded in a 5-coordinate geometry to two equivalent Sm(2), two equivalent Sm(3), and one C(1) atom. In the fourth C site, C(4) is bonded to one Sm(1), two equivalent Sm(2), two equivalent Sm(3), and one Os(2) atom to form CSm5Os octahedra that share corners with five equivalent C(4)Sm5Os octahedra, edges with two equivalent C(2)Sm4Os2 octahedra, and edges with three equivalent C(4)Sm5Os octahedra. The corner-sharing octahedral tilt angles range from 7-45°.