Li3ErCl6 is Corundum-derived structured and crystallizes in the trigonal P321 space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent Cl(1), two equivalent Cl(2), and two equivalent Cl(3) atoms to form LiCl6 octahedra that share corners with two equivalent Er(2)Cl6 octahedra, corners with six equivalent Li(3)Cl6 octahedra, edges with two equivalent Er(1)Cl6 octahedra, and faces with two equivalent Li(2)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 45-51°. In the second Li site, Li(2) is bonded to two equivalent Cl(1), two equivalent Cl(2), and two equivalent Cl(3) atoms to form LiCl6 octahedra that share corners with four equivalent Er(1)Cl6 octahedra,  an edgeedge with one Er(2)Cl6 octahedra, edges with three equivalent Li(3)Cl6 octahedra, and faces with two equivalent Li(1)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 45-48°. In the third Li site, Li(3) is bonded to two equivalent Cl(1), two equivalent Cl(2), and two equivalent Cl(3) atoms to form LiCl6 octahedra that share corners with four equivalent Er(1)Cl6 octahedra, corners with six equivalent Li(1)Cl6 octahedra,  an edgeedge with one Er(2)Cl6 octahedra, and edges with three equivalent Li(2)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 45-53°. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to three equivalent Cl(2) and three equivalent Cl(3) atoms to form ErCl6 octahedra that share corners with six equivalent Li(2)Cl6 octahedra, corners with six equivalent Li(3)Cl6 octahedra, and edges with three equivalent Li(1)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 45-53°. In the second Er site, Er(2) is bonded to six equivalent Cl(1) atoms to form ErCl6 octahedra that share corners with six equivalent Li(1)Cl6 octahedra, edges with three equivalent Li(2)Cl6 octahedra, and edges with three equivalent Li(3)Cl6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are three inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a rectangular see-saw-like geometry to one Li(1), one Li(2), one Li(3), and one Er(2) atom. In the second Cl site, Cl(2) is bonded in a rectangular see-saw-like geometry to one Li(1), one Li(2), one Li(3), and one Er(1) atom. In the third Cl site, Cl(3) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(2), one Li(3), and one Er(1) atom.
Li3ErCl6 is Corundum-derived structured and crystallizes in the trigonal P321 space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent Cl(1), two equivalent Cl(2), and two equivalent Cl(3) atoms to form LiCl6 octahedra that share corners with two equivalent Er(2)Cl6 octahedra, corners with six equivalent Li(3)Cl6 octahedra, edges with two equivalent Er(1)Cl6 octahedra, and faces with two equivalent Li(2)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 45-51°. Both Li(1)-Cl(1) bond lengths are 2.53 Å. Both Li(1)-Cl(2) bond lengths are 2.63 Å. Both Li(1)-Cl(3) bond lengths are 2.50 Å. In the second Li site, Li(2) is bonded to two equivalent Cl(1), two equivalent Cl(2), and two equivalent Cl(3) atoms to form LiCl6 octahedra that share corners with four equivalent Er(1)Cl6 octahedra,  an edgeedge with one Er(2)Cl6 octahedra, edges with three equivalent Li(3)Cl6 octahedra, and faces with two equivalent Li(1)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 45-48°. Both Li(2)-Cl(1) bond lengths are 2.54 Å. Both Li(2)-Cl(2) bond lengths are 2.49 Å. Both Li(2)-Cl(3) bond lengths are 2.58 Å. In the third Li site, Li(3) is bonded to two equivalent Cl(1), two equivalent Cl(2), and two equivalent Cl(3) atoms to form LiCl6 octahedra that share corners with four equivalent Er(1)Cl6 octahedra, corners with six equivalent Li(1)Cl6 octahedra,  an edgeedge with one Er(2)Cl6 octahedra, and edges with three equivalent Li(2)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 45-53°. Both Li(3)-Cl(1) bond lengths are 2.60 Å. Both Li(3)-Cl(2) bond lengths are 2.56 Å. Both Li(3)-Cl(3) bond lengths are 2.67 Å. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to three equivalent Cl(2) and three equivalent Cl(3) atoms to form ErCl6 octahedra that share corners with six equivalent Li(2)Cl6 octahedra, corners with six equivalent Li(3)Cl6 octahedra, and edges with three equivalent Li(1)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 45-53°. All Er(1)-Cl(2) bond lengths are 2.62 Å. All Er(1)-Cl(3) bond lengths are 2.61 Å. In the second Er site, Er(2) is bonded to six equivalent Cl(1) atoms to form ErCl6 octahedra that share corners with six equivalent Li(1)Cl6 octahedra, edges with three equivalent Li(2)Cl6 octahedra, and edges with three equivalent Li(3)Cl6 octahedra. The corner-sharing octahedral tilt angles are 51°. All Er(2)-Cl(1) bond lengths are 2.60 Å. There are three inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a rectangular see-saw-like geometry to one Li(1), one Li(2), one Li(3), and one Er(2) atom. In the second Cl site, Cl(2) is bonded in a rectangular see-saw-like geometry to one Li(1), one Li(2), one Li(3), and one Er(1) atom. In the third Cl site, Cl(3) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(2), one Li(3), and one Er(1) atom.