LaCN2Cl crystallizes in the monoclinic P2_1/m space group. La(1) is bonded in a 9-coordinate geometry to two equivalent N(1), three equivalent N(2), and four equivalent Cl(1) atoms. C(1) is bonded in a linear geometry to one N(1) and one N(2) atom. There are two inequivalent N sites. In the first N site, N(1) is bonded in a distorted trigonal planar geometry to two equivalent La(1) and one C(1) atom. In the second N site, N(2) is bonded to three equivalent La(1) and one C(1) atom to form distorted NLa3C tetrahedra that share corners with two equivalent N(2)La3C tetrahedra, corners with ten equivalent Cl(1)La4 tetrahedra,  an edgeedge with one Cl(1)La4 tetrahedra, and edges with two equivalent N(2)La3C tetrahedra. Cl(1) is bonded to four equivalent La(1) atoms to form ClLa4 tetrahedra that share corners with four equivalent Cl(1)La4 tetrahedra, corners with ten equivalent N(2)La3C tetrahedra,  an edgeedge with one N(2)La3C tetrahedra, and edges with four equivalent Cl(1)La4 tetrahedra.
LaCN2Cl crystallizes in the monoclinic P2_1/m space group. La(1) is bonded in a 9-coordinate geometry to two equivalent N(1), three equivalent N(2), and four equivalent Cl(1) atoms. Both La(1)-N(1) bond lengths are 2.56 Å. There are two shorter (2.64 Å) and one longer (2.67 Å) La(1)-N(2) bond length. There are a spread of La(1)-Cl(1) bond distances ranging from 3.06-3.21 Å. C(1) is bonded in a linear geometry to one N(1) and one N(2) atom. The C(1)-N(1) bond length is 1.22 Å. The C(1)-N(2) bond length is 1.25 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded in a distorted trigonal planar geometry to two equivalent La(1) and one C(1) atom. In the second N site, N(2) is bonded to three equivalent La(1) and one C(1) atom to form distorted NLa3C tetrahedra that share corners with two equivalent N(2)La3C tetrahedra, corners with ten equivalent Cl(1)La4 tetrahedra,  an edgeedge with one Cl(1)La4 tetrahedra, and edges with two equivalent N(2)La3C tetrahedra. Cl(1) is bonded to four equivalent La(1) atoms to form ClLa4 tetrahedra that share corners with four equivalent Cl(1)La4 tetrahedra, corners with ten equivalent N(2)La3C tetrahedra,  an edgeedge with one N(2)La3C tetrahedra, and edges with four equivalent Cl(1)La4 tetrahedra.