La7Os4C9 is Orthorhombic Perovskite-like structured and crystallizes in the monoclinic C2/m space group. There are four inequivalent La sites. In the first La site, La(1) is bonded in a 7-coordinate geometry to one C(1), one C(3), one C(5), two equivalent C(2), and two equivalent C(4) atoms. In the second La site, La(2) is bonded in a 4-coordinate geometry to one C(2), one C(3), and two equivalent C(1) atoms. In the third La site, La(3) is bonded in a 5-coordinate geometry to one C(1), one C(2), one C(4), and two equivalent C(3) atoms. In the fourth La site, La(4) is bonded in a square co-planar geometry to two equivalent C(2) and two equivalent C(5) atoms. There are two inequivalent Os sites. In the first Os site, Os(1) is bonded in a trigonal planar geometry to one C(1), one C(4), and one C(5) atom. In the second Os site, Os(2) is bonded in a 3-coordinate geometry to one C(1) and two equivalent C(3) atoms. There are five inequivalent C sites. In the first C site, C(1) is bonded to one La(1), one La(3), two equivalent La(2), one Os(1), and one Os(2) atom to form CLa4Os2 octahedra that share  a cornercorner with one C(3)La4Os2 octahedra,  a cornercorner with one C(2)La5C octahedra, corners with two equivalent C(1)La4Os2 octahedra,  an edgeedge with one C(5)La4Os2 octahedra, edges with two equivalent C(2)La5C octahedra, and edges with three equivalent C(3)La4Os2 octahedra. The corner-sharing octahedral tilt angles range from 18-77°. In the second C site, C(2) is bonded to one La(2), one La(3), one La(4), two equivalent La(1), and one C(4) atom to form distorted CLa5C octahedra that share  a cornercorner with one C(1)La4Os2 octahedra,  a cornercorner with one C(3)La4Os2 octahedra, corners with three equivalent C(2)La5C octahedra, edges with two equivalent C(1)La4Os2 octahedra, edges with two equivalent C(3)La4Os2 octahedra, and edges with two equivalent C(5)La4Os2 octahedra. The corner-sharing octahedral tilt angles range from 0-77°. In the third C site, C(3) is bonded to one La(1), one La(2), two equivalent La(3), and two equivalent Os(2) atoms to form CLa4Os2 octahedra that share  a cornercorner with one C(1)La4Os2 octahedra,  a cornercorner with one C(5)La4Os2 octahedra,  a cornercorner with one C(2)La5C octahedra, corners with two equivalent C(3)La4Os2 octahedra,  an edgeedge with one C(3)La4Os2 octahedra, edges with two equivalent C(2)La5C octahedra, and edges with three equivalent C(1)La4Os2 octahedra. The corner-sharing octahedral tilt angles range from 15-35°. In the fourth C site, C(4) is bonded in a 5-coordinate geometry to one La(3), two equivalent La(1), one Os(1), and one C(2) atom. In the fifth C site, C(5) is bonded to two equivalent La(1), two equivalent La(4), and two equivalent Os(1) atoms to form CLa4Os2 octahedra that share corners with two equivalent C(3)La4Os2 octahedra, corners with two equivalent C(5)La4Os2 octahedra, edges with two equivalent C(1)La4Os2 octahedra, and edges with four equivalent C(2)La5C octahedra. The corner-sharing octahedral tilt angles range from 0-35°.
La7Os4C9 is Orthorhombic Perovskite-like structured and crystallizes in the monoclinic C2/m space group. There are four inequivalent La sites. In the first La site, La(1) is bonded in a 7-coordinate geometry to one C(1), one C(3), one C(5), two equivalent C(2), and two equivalent C(4) atoms. The La(1)-C(1) bond length is 2.77 Å. The La(1)-C(3) bond length is 2.70 Å. The La(1)-C(5) bond length is 2.80 Å. Both La(1)-C(2) bond lengths are 2.77 Å. Both La(1)-C(4) bond lengths are 2.84 Å. In the second La site, La(2) is bonded in a 4-coordinate geometry to one C(2), one C(3), and two equivalent C(1) atoms. The La(2)-C(2) bond length is 2.64 Å. The La(2)-C(3) bond length is 2.78 Å. Both La(2)-C(1) bond lengths are 2.75 Å. In the third La site, La(3) is bonded in a 5-coordinate geometry to one C(1), one C(2), one C(4), and two equivalent C(3) atoms. The La(3)-C(1) bond length is 2.77 Å. The La(3)-C(2) bond length is 2.76 Å. The La(3)-C(4) bond length is 2.68 Å. Both La(3)-C(3) bond lengths are 2.74 Å. In the fourth La site, La(4) is bonded in a square co-planar geometry to two equivalent C(2) and two equivalent C(5) atoms. Both La(4)-C(2) bond lengths are 2.65 Å. Both La(4)-C(5) bond lengths are 2.72 Å. There are two inequivalent Os sites. In the first Os site, Os(1) is bonded in a trigonal planar geometry to one C(1), one C(4), and one C(5) atom. The Os(1)-C(1) bond length is 1.93 Å. The Os(1)-C(4) bond length is 1.92 Å. The Os(1)-C(5) bond length is 1.93 Å. In the second Os site, Os(2) is bonded in a 3-coordinate geometry to one C(1) and two equivalent C(3) atoms. The Os(2)-C(1) bond length is 1.94 Å. There is one shorter (1.96 Å) and one longer (2.08 Å) Os(2)-C(3) bond length. There are five inequivalent C sites. In the first C site, C(1) is bonded to one La(1), one La(3), two equivalent La(2), one Os(1), and one Os(2) atom to form CLa4Os2 octahedra that share  a cornercorner with one C(3)La4Os2 octahedra,  a cornercorner with one C(2)La5C octahedra, corners with two equivalent C(1)La4Os2 octahedra,  an edgeedge with one C(5)La4Os2 octahedra, edges with two equivalent C(2)La5C octahedra, and edges with three equivalent C(3)La4Os2 octahedra. The corner-sharing octahedral tilt angles range from 18-77°. In the second C site, C(2) is bonded to one La(2), one La(3), one La(4), two equivalent La(1), and one C(4) atom to form distorted CLa5C octahedra that share  a cornercorner with one C(1)La4Os2 octahedra,  a cornercorner with one C(3)La4Os2 octahedra, corners with three equivalent C(2)La5C octahedra, edges with two equivalent C(1)La4Os2 octahedra, edges with two equivalent C(3)La4Os2 octahedra, and edges with two equivalent C(5)La4Os2 octahedra. The corner-sharing octahedral tilt angles range from 0-77°. The C(2)-C(4) bond length is 1.32 Å. In the third C site, C(3) is bonded to one La(1), one La(2), two equivalent La(3), and two equivalent Os(2) atoms to form CLa4Os2 octahedra that share  a cornercorner with one C(1)La4Os2 octahedra,  a cornercorner with one C(5)La4Os2 octahedra,  a cornercorner with one C(2)La5C octahedra, corners with two equivalent C(3)La4Os2 octahedra,  an edgeedge with one C(3)La4Os2 octahedra, edges with two equivalent C(2)La5C octahedra, and edges with three equivalent C(1)La4Os2 octahedra. The corner-sharing octahedral tilt angles range from 15-35°. In the fourth C site, C(4) is bonded in a 5-coordinate geometry to one La(3), two equivalent La(1), one Os(1), and one C(2) atom. In the fifth C site, C(5) is bonded to two equivalent La(1), two equivalent La(4), and two equivalent Os(1) atoms to form CLa4Os2 octahedra that share corners with two equivalent C(3)La4Os2 octahedra, corners with two equivalent C(5)La4Os2 octahedra, edges with two equivalent C(1)La4Os2 octahedra, and edges with four equivalent C(2)La5C octahedra. The corner-sharing octahedral tilt angles range from 0-35°.