Eu2C(NCl)2 crystallizes in the monoclinic C2/m space group. Eu(1) is bonded in a 7-coordinate geometry to three equivalent N(1) and four equivalent Cl(1) atoms. C(1) is bonded in a linear geometry to two equivalent N(1) atoms. N(1) is bonded to three equivalent Eu(1) and one C(1) atom to form distorted NEu3C tetrahedra that share corners with three equivalent N(1)Eu3C tetrahedra, corners with ten equivalent Cl(1)Eu4 tetrahedra,  an edgeedge with one Cl(1)Eu4 tetrahedra, and edges with two equivalent N(1)Eu3C tetrahedra. Cl(1) is bonded to four equivalent Eu(1) atoms to form ClEu4 tetrahedra that share corners with six equivalent Cl(1)Eu4 tetrahedra, corners with ten equivalent N(1)Eu3C tetrahedra,  an edgeedge with one N(1)Eu3C tetrahedra, and edges with three equivalent Cl(1)Eu4 tetrahedra.
Eu2C(NCl)2 crystallizes in the monoclinic C2/m space group. Eu(1) is bonded in a 7-coordinate geometry to three equivalent N(1) and four equivalent Cl(1) atoms. There are two shorter (2.59 Å) and one longer (2.61 Å) Eu(1)-N(1) bond length. There are two shorter (3.00 Å) and two longer (3.02 Å) Eu(1)-Cl(1) bond lengths. C(1) is bonded in a linear geometry to two equivalent N(1) atoms. Both C(1)-N(1) bond lengths are 1.24 Å. N(1) is bonded to three equivalent Eu(1) and one C(1) atom to form distorted NEu3C tetrahedra that share corners with three equivalent N(1)Eu3C tetrahedra, corners with ten equivalent Cl(1)Eu4 tetrahedra,  an edgeedge with one Cl(1)Eu4 tetrahedra, and edges with two equivalent N(1)Eu3C tetrahedra. Cl(1) is bonded to four equivalent Eu(1) atoms to form ClEu4 tetrahedra that share corners with six equivalent Cl(1)Eu4 tetrahedra, corners with ten equivalent N(1)Eu3C tetrahedra,  an edgeedge with one N(1)Eu3C tetrahedra, and edges with three equivalent Cl(1)Eu4 tetrahedra.