Ce18C18Cl11 crystallizes in the triclinic P-1 space group. There are nine inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 8-coordinate geometry to one C(8), two equivalent C(2), two equivalent C(4), one Cl(1), one Cl(2), and one Cl(4) atom. In the second Ce site, Ce(2) is bonded in a 8-coordinate geometry to one C(5), two equivalent C(1), two equivalent C(7), one Cl(3), and two equivalent Cl(6) atoms. In the third Ce site, Ce(3) is bonded in a 8-coordinate geometry to one C(3), one C(5), one C(7), two equivalent C(1), one Cl(3), one Cl(5), and one Cl(6) atom. In the fourth Ce site, Ce(4) is bonded in a 8-coordinate geometry to one C(1), one C(3), one C(5), one C(7), one C(9), one Cl(3), and two equivalent Cl(6) atoms. In the fifth Ce site, Ce(5) is bonded in a 9-coordinate geometry to one C(3), one C(5), one C(6), one C(7), one C(8), one C(9), one Cl(1), one Cl(3), and one Cl(5) atom. In the sixth Ce site, Ce(6) is bonded in a 8-coordinate geometry to one C(2), one C(6), one C(8), two equivalent C(4), one Cl(4), and two equivalent Cl(2) atoms. In the seventh Ce site, Ce(7) is bonded in a 9-coordinate geometry to one C(2), one C(3), one C(4), one C(6), one C(8), one C(9), one Cl(1), one Cl(2), and one Cl(5) atom. In the eighth Ce site, Ce(8) is bonded in a 7-coordinate geometry to one C(2), one C(6), one C(8), one C(9), one Cl(1), one Cl(2), and one Cl(4) atom. In the ninth Ce site, Ce(9) is bonded in a 2-coordinate geometry to one C(3), one C(5), one C(6), one C(9), one Cl(3), one Cl(5), and one Cl(6) atom. There are nine inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to one Ce(4), two equivalent Ce(2), two equivalent Ce(3), and one C(1) atom. In the second C site, C(2) is bonded in a 6-coordinate geometry to one Ce(6), one Ce(7), one Ce(8), two equivalent Ce(1), and one C(4) atom. In the third C site, C(3) is bonded to one Ce(3), one Ce(4), one Ce(5), one Ce(7), one Ce(9), and one C(9) atom to form distorted CCe5C octahedra that share corners with two equivalent C(8)Ce5C octahedra,  a cornercorner with one Cl(2)Ce5 trigonal bipyramid, corners with two equivalent Cl(3)Ce5 trigonal bipyramids, and  an edgeedge with one Cl(3)Ce5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 66-67°. In the fourth C site, C(4) is bonded in a 6-coordinate geometry to one Ce(7), two equivalent Ce(1), two equivalent Ce(6), and one C(2) atom. In the fifth C site, C(5) is bonded in a 6-coordinate geometry to one Ce(2), one Ce(3), one Ce(4), one Ce(5), one Ce(9), and one C(7) atom. In the sixth C site, C(6) is bonded in a 6-coordinate geometry to one Ce(5), one Ce(6), one Ce(7), one Ce(8), one Ce(9), and one C(8) atom. In the seventh C site, C(7) is bonded in a 6-coordinate geometry to one Ce(3), one Ce(4), one Ce(5), two equivalent Ce(2), and one C(5) atom. In the eighth C site, C(8) is bonded to one Ce(1), one Ce(5), one Ce(6), one Ce(7), one Ce(8), and one C(6) atom to form distorted CCe5C octahedra that share  a cornercorner with one Cl(4)Ce6 octahedra, corners with two equivalent C(3)Ce5C octahedra,  a cornercorner with one Cl(3)Ce5 trigonal bipyramid, corners with three equivalent Cl(2)Ce5 trigonal bipyramids,  an edgeedge with one Cl(4)Ce6 octahedra, and  an edgeedge with one Cl(2)Ce5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 22-67°. In the ninth C site, C(9) is bonded in a 6-coordinate geometry to one Ce(4), one Ce(5), one Ce(7), one Ce(8), one Ce(9), and one C(3) atom. There are six inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a distorted rectangular see-saw-like geometry to one Ce(1), one Ce(5), one Ce(7), and one Ce(8) atom. In the second Cl site, Cl(2) is bonded to one Ce(1), one Ce(7), one Ce(8), and two equivalent Ce(6) atoms to form distorted ClCe5 trigonal bipyramids that share  a cornercorner with one C(3)Ce5C octahedra, corners with three equivalent C(8)Ce5C octahedra,  an edgeedge with one C(8)Ce5C octahedra, edges with two equivalent Cl(4)Ce6 octahedra, and  an edgeedge with one Cl(2)Ce5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 14-59°. In the third Cl site, Cl(3) is bonded to one Ce(2), one Ce(3), one Ce(4), one Ce(5), and one Ce(9) atom to form distorted ClCe5 trigonal bipyramids that share  a cornercorner with one C(8)Ce5C octahedra, corners with two equivalent C(3)Ce5C octahedra, and  an edgeedge with one C(3)Ce5C octahedra. The corner-sharing octahedral tilt angles range from 29-58°. In the fourth Cl site, Cl(4) is bonded to two equivalent Ce(1), two equivalent Ce(6), and two equivalent Ce(8) atoms to form distorted ClCe6 octahedra that share corners with two equivalent C(8)Ce5C octahedra, edges with two equivalent C(8)Ce5C octahedra, and edges with four equivalent Cl(2)Ce5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 22°. In the fifth Cl site, Cl(5) is bonded in a distorted rectangular see-saw-like geometry to one Ce(3), one Ce(5), one Ce(7), and one Ce(9) atom. In the sixth Cl site, Cl(6) is bonded in a 6-coordinate geometry to one Ce(3), one Ce(9), two equivalent Ce(2), and two equivalent Ce(4) atoms.
Ce18C18Cl11 crystallizes in the triclinic P-1 space group. There are nine inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 8-coordinate geometry to one C(8), two equivalent C(2), two equivalent C(4), one Cl(1), one Cl(2), and one Cl(4) atom. The Ce(1)-C(8) bond length is 2.33 Å. There is one shorter (2.60 Å) and one longer (2.67 Å) Ce(1)-C(2) bond length. Both Ce(1)-C(4) bond lengths are 2.61 Å. The Ce(1)-Cl(1) bond length is 2.90 Å. The Ce(1)-Cl(2) bond length is 2.95 Å. The Ce(1)-Cl(4) bond length is 3.16 Å. In the second Ce site, Ce(2) is bonded in a 8-coordinate geometry to one C(5), two equivalent C(1), two equivalent C(7), one Cl(3), and two equivalent Cl(6) atoms. The Ce(2)-C(5) bond length is 2.70 Å. There is one shorter (2.58 Å) and one longer (2.62 Å) Ce(2)-C(1) bond length. There is one shorter (2.32 Å) and one longer (2.62 Å) Ce(2)-C(7) bond length. The Ce(2)-Cl(3) bond length is 2.95 Å. There is one shorter (2.99 Å) and one longer (3.20 Å) Ce(2)-Cl(6) bond length. In the third Ce site, Ce(3) is bonded in a 8-coordinate geometry to one C(3), one C(5), one C(7), two equivalent C(1), one Cl(3), one Cl(5), and one Cl(6) atom. The Ce(3)-C(3) bond length is 2.34 Å. The Ce(3)-C(5) bond length is 2.60 Å. The Ce(3)-C(7) bond length is 2.61 Å. There is one shorter (2.56 Å) and one longer (2.61 Å) Ce(3)-C(1) bond length. The Ce(3)-Cl(3) bond length is 2.98 Å. The Ce(3)-Cl(5) bond length is 2.87 Å. The Ce(3)-Cl(6) bond length is 3.17 Å. In the fourth Ce site, Ce(4) is bonded in a 8-coordinate geometry to one C(1), one C(3), one C(5), one C(7), one C(9), one Cl(3), and two equivalent Cl(6) atoms. The Ce(4)-C(1) bond length is 2.30 Å. The Ce(4)-C(3) bond length is 2.62 Å. The Ce(4)-C(5) bond length is 2.61 Å. The Ce(4)-C(7) bond length is 2.55 Å. The Ce(4)-C(9) bond length is 2.88 Å. The Ce(4)-Cl(3) bond length is 3.19 Å. There is one shorter (3.09 Å) and one longer (3.24 Å) Ce(4)-Cl(6) bond length. In the fifth Ce site, Ce(5) is bonded in a 9-coordinate geometry to one C(3), one C(5), one C(6), one C(7), one C(8), one C(9), one Cl(1), one Cl(3), and one Cl(5) atom. The Ce(5)-C(3) bond length is 2.62 Å. The Ce(5)-C(5) bond length is 2.60 Å. The Ce(5)-C(6) bond length is 2.68 Å. The Ce(5)-C(7) bond length is 2.68 Å. The Ce(5)-C(8) bond length is 2.70 Å. The Ce(5)-C(9) bond length is 2.54 Å. The Ce(5)-Cl(1) bond length is 2.95 Å. The Ce(5)-Cl(3) bond length is 3.30 Å. The Ce(5)-Cl(5) bond length is 2.96 Å. In the sixth Ce site, Ce(6) is bonded in a 8-coordinate geometry to one C(2), one C(6), one C(8), two equivalent C(4), one Cl(4), and two equivalent Cl(2) atoms. The Ce(6)-C(2) bond length is 2.59 Å. The Ce(6)-C(6) bond length is 2.89 Å. The Ce(6)-C(8) bond length is 2.64 Å. There is one shorter (2.31 Å) and one longer (2.56 Å) Ce(6)-C(4) bond length. The Ce(6)-Cl(4) bond length is 3.05 Å. There is one shorter (3.01 Å) and one longer (3.23 Å) Ce(6)-Cl(2) bond length. In the seventh Ce site, Ce(7) is bonded in a 9-coordinate geometry to one C(2), one C(3), one C(4), one C(6), one C(8), one C(9), one Cl(1), one Cl(2), and one Cl(5) atom. The Ce(7)-C(2) bond length is 2.60 Å. The Ce(7)-C(3) bond length is 2.70 Å. The Ce(7)-C(4) bond length is 2.68 Å. The Ce(7)-C(6) bond length is 2.56 Å. The Ce(7)-C(8) bond length is 2.63 Å. The Ce(7)-C(9) bond length is 2.69 Å. The Ce(7)-Cl(1) bond length is 2.95 Å. The Ce(7)-Cl(2) bond length is 3.25 Å. The Ce(7)-Cl(5) bond length is 2.96 Å. In the eighth Ce site, Ce(8) is bonded in a 7-coordinate geometry to one C(2), one C(6), one C(8), one C(9), one Cl(1), one Cl(2), and one Cl(4) atom. The Ce(8)-C(2) bond length is 2.31 Å. The Ce(8)-C(6) bond length is 2.63 Å. The Ce(8)-C(8) bond length is 2.58 Å. The Ce(8)-C(9) bond length is 2.32 Å. The Ce(8)-Cl(1) bond length is 3.04 Å. The Ce(8)-Cl(2) bond length is 3.18 Å. The Ce(8)-Cl(4) bond length is 3.41 Å. In the ninth Ce site, Ce(9) is bonded in a 2-coordinate geometry to one C(3), one C(5), one C(6), one C(9), one Cl(3), one Cl(5), and one Cl(6) atom. The Ce(9)-C(3) bond length is 2.58 Å. The Ce(9)-C(5) bond length is 2.32 Å. The Ce(9)-C(6) bond length is 2.31 Å. The Ce(9)-C(9) bond length is 2.63 Å. The Ce(9)-Cl(3) bond length is 3.21 Å. The Ce(9)-Cl(5) bond length is 3.02 Å. The Ce(9)-Cl(6) bond length is 3.59 Å. There are nine inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to one Ce(4), two equivalent Ce(2), two equivalent Ce(3), and one C(1) atom. The C(1)-C(1) bond length is 1.40 Å. In the second C site, C(2) is bonded in a 6-coordinate geometry to one Ce(6), one Ce(7), one Ce(8), two equivalent Ce(1), and one C(4) atom. The C(2)-C(4) bond length is 1.39 Å. In the third C site, C(3) is bonded to one Ce(3), one Ce(4), one Ce(5), one Ce(7), one Ce(9), and one C(9) atom to form distorted CCe5C octahedra that share corners with two equivalent C(8)Ce5C octahedra,  a cornercorner with one Cl(2)Ce5 trigonal bipyramid, corners with two equivalent Cl(3)Ce5 trigonal bipyramids, and  an edgeedge with one Cl(3)Ce5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 66-67°. The C(3)-C(9) bond length is 1.39 Å. In the fourth C site, C(4) is bonded in a 6-coordinate geometry to one Ce(7), two equivalent Ce(1), two equivalent Ce(6), and one C(2) atom. In the fifth C site, C(5) is bonded in a 6-coordinate geometry to one Ce(2), one Ce(3), one Ce(4), one Ce(5), one Ce(9), and one C(7) atom. The C(5)-C(7) bond length is 1.40 Å. In the sixth C site, C(6) is bonded in a 6-coordinate geometry to one Ce(5), one Ce(6), one Ce(7), one Ce(8), one Ce(9), and one C(8) atom. The C(6)-C(8) bond length is 1.39 Å. In the seventh C site, C(7) is bonded in a 6-coordinate geometry to one Ce(3), one Ce(4), one Ce(5), two equivalent Ce(2), and one C(5) atom. In the eighth C site, C(8) is bonded to one Ce(1), one Ce(5), one Ce(6), one Ce(7), one Ce(8), and one C(6) atom to form distorted CCe5C octahedra that share  a cornercorner with one Cl(4)Ce6 octahedra, corners with two equivalent C(3)Ce5C octahedra,  a cornercorner with one Cl(3)Ce5 trigonal bipyramid, corners with three equivalent Cl(2)Ce5 trigonal bipyramids,  an edgeedge with one Cl(4)Ce6 octahedra, and  an edgeedge with one Cl(2)Ce5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 22-67°. In the ninth C site, C(9) is bonded in a 6-coordinate geometry to one Ce(4), one Ce(5), one Ce(7), one Ce(8), one Ce(9), and one C(3) atom. There are six inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a distorted rectangular see-saw-like geometry to one Ce(1), one Ce(5), one Ce(7), and one Ce(8) atom. In the second Cl site, Cl(2) is bonded to one Ce(1), one Ce(7), one Ce(8), and two equivalent Ce(6) atoms to form distorted ClCe5 trigonal bipyramids that share  a cornercorner with one C(3)Ce5C octahedra, corners with three equivalent C(8)Ce5C octahedra,  an edgeedge with one C(8)Ce5C octahedra, edges with two equivalent Cl(4)Ce6 octahedra, and  an edgeedge with one Cl(2)Ce5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 14-59°. In the third Cl site, Cl(3) is bonded to one Ce(2), one Ce(3), one Ce(4), one Ce(5), and one Ce(9) atom to form distorted ClCe5 trigonal bipyramids that share  a cornercorner with one C(8)Ce5C octahedra, corners with two equivalent C(3)Ce5C octahedra, and  an edgeedge with one C(3)Ce5C octahedra. The corner-sharing octahedral tilt angles range from 29-58°. In the fourth Cl site, Cl(4) is bonded to two equivalent Ce(1), two equivalent Ce(6), and two equivalent Ce(8) atoms to form distorted ClCe6 octahedra that share corners with two equivalent C(8)Ce5C octahedra, edges with two equivalent C(8)Ce5C octahedra, and edges with four equivalent Cl(2)Ce5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 22°. In the fifth Cl site, Cl(5) is bonded in a distorted rectangular see-saw-like geometry to one Ce(3), one Ce(5), one Ce(7), and one Ce(9) atom. In the sixth Cl site, Cl(6) is bonded in a 6-coordinate geometry to one Ce(3), one Ce(9), two equivalent Ce(2), and two equivalent Ce(4) atoms.