Li16Ta2N8O crystallizes in the trigonal R-3 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to one N(2) and three equivalent N(1) atoms to form distorted LiN4 tetrahedra that share corners with three equivalent Li(2)N3O tetrahedra, corners with three equivalent Li(3)N3O tetrahedra, corners with four equivalent Ta(1)N4 tetrahedra, corners with six equivalent Li(4)N4 tetrahedra, edges with three equivalent Li(3)N3O tetrahedra, and edges with three equivalent Li(4)N4 tetrahedra. In the second Li site, Li(2) is bonded to three equivalent N(1) and one O(1) atom to form distorted LiN3O tetrahedra that share  a cornercorner with one Li(2)N3O tetrahedra, corners with three equivalent Li(3)N3O tetrahedra, corners with three equivalent Li(1)N4 tetrahedra, corners with three equivalent Ta(1)N4 tetrahedra, corners with six equivalent Li(4)N4 tetrahedra, edges with three equivalent Li(3)N3O tetrahedra, and edges with three equivalent Li(4)N4 tetrahedra. In the third Li site, Li(3) is bonded to one N(1), two equivalent N(2), and one O(1) atom to form distorted LiN3O tetrahedra that share  a cornercorner with one Li(2)N3O tetrahedra,  a cornercorner with one Li(1)N4 tetrahedra,  a cornercorner with one Ta(1)N4 tetrahedra, corners with four equivalent Li(4)N4 tetrahedra, corners with nine equivalent Li(3)N3O tetrahedra,  an edgeedge with one Li(2)N3O tetrahedra,  an edgeedge with one Li(1)N4 tetrahedra,  an edgeedge with one Ta(1)N4 tetrahedra, and edges with three equivalent Li(3)N3O tetrahedra. In the fourth Li site, Li(4) is bonded to four equivalent N(1) atoms to form distorted LiN4 tetrahedra that share corners with two equivalent Li(2)N3O tetrahedra, corners with two equivalent Li(1)N4 tetrahedra, corners with two equivalent Ta(1)N4 tetrahedra, corners with four equivalent Li(3)N3O tetrahedra, corners with six equivalent Li(4)N4 tetrahedra,  an edgeedge with one Li(2)N3O tetrahedra,  an edgeedge with one Li(1)N4 tetrahedra,  an edgeedge with one Ta(1)N4 tetrahedra, and edges with three equivalent Li(4)N4 tetrahedra. Ta(1) is bonded to one N(2) and three equivalent N(1) atoms to form TaN4 tetrahedra that share corners with three equivalent Li(2)N3O tetrahedra, corners with three equivalent Li(3)N3O tetrahedra, corners with four equivalent Li(1)N4 tetrahedra, corners with six equivalent Li(4)N4 tetrahedra, edges with three equivalent Li(3)N3O tetrahedra, and edges with three equivalent Li(4)N4 tetrahedra. There are two inequivalent N sites. In the first N site, N(1) is bonded in a distorted body-centered cubic geometry to one Li(1), one Li(2), one Li(3), four equivalent Li(4), and one Ta(1) atom. In the second N site, N(2) is bonded in a distorted body-centered cubic geometry to one Li(1), six equivalent Li(3), and one Ta(1) atom. O(1) is bonded in a body-centered cubic geometry to two equivalent Li(2) and six equivalent Li(3) atoms.
Li16Ta2N8O crystallizes in the trigonal R-3 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to one N(2) and three equivalent N(1) atoms to form distorted LiN4 tetrahedra that share corners with three equivalent Li(2)N3O tetrahedra, corners with three equivalent Li(3)N3O tetrahedra, corners with four equivalent Ta(1)N4 tetrahedra, corners with six equivalent Li(4)N4 tetrahedra, edges with three equivalent Li(3)N3O tetrahedra, and edges with three equivalent Li(4)N4 tetrahedra. The Li(1)-N(2) bond length is 2.33 Å. All Li(1)-N(1) bond lengths are 2.16 Å. In the second Li site, Li(2) is bonded to three equivalent N(1) and one O(1) atom to form distorted LiN3O tetrahedra that share  a cornercorner with one Li(2)N3O tetrahedra, corners with three equivalent Li(3)N3O tetrahedra, corners with three equivalent Li(1)N4 tetrahedra, corners with three equivalent Ta(1)N4 tetrahedra, corners with six equivalent Li(4)N4 tetrahedra, edges with three equivalent Li(3)N3O tetrahedra, and edges with three equivalent Li(4)N4 tetrahedra. All Li(2)-N(1) bond lengths are 2.22 Å. The Li(2)-O(1) bond length is 1.99 Å. In the third Li site, Li(3) is bonded to one N(1), two equivalent N(2), and one O(1) atom to form distorted LiN3O tetrahedra that share  a cornercorner with one Li(2)N3O tetrahedra,  a cornercorner with one Li(1)N4 tetrahedra,  a cornercorner with one Ta(1)N4 tetrahedra, corners with four equivalent Li(4)N4 tetrahedra, corners with nine equivalent Li(3)N3O tetrahedra,  an edgeedge with one Li(2)N3O tetrahedra,  an edgeedge with one Li(1)N4 tetrahedra,  an edgeedge with one Ta(1)N4 tetrahedra, and edges with three equivalent Li(3)N3O tetrahedra. The Li(3)-N(1) bond length is 2.20 Å. There is one shorter (2.04 Å) and one longer (2.22 Å) Li(3)-N(2) bond length. The Li(3)-O(1) bond length is 2.05 Å. In the fourth Li site, Li(4) is bonded to four equivalent N(1) atoms to form distorted LiN4 tetrahedra that share corners with two equivalent Li(2)N3O tetrahedra, corners with two equivalent Li(1)N4 tetrahedra, corners with two equivalent Ta(1)N4 tetrahedra, corners with four equivalent Li(3)N3O tetrahedra, corners with six equivalent Li(4)N4 tetrahedra,  an edgeedge with one Li(2)N3O tetrahedra,  an edgeedge with one Li(1)N4 tetrahedra,  an edgeedge with one Ta(1)N4 tetrahedra, and edges with three equivalent Li(4)N4 tetrahedra. There are a spread of Li(4)-N(1) bond distances ranging from 2.06-2.34 Å. Ta(1) is bonded to one N(2) and three equivalent N(1) atoms to form TaN4 tetrahedra that share corners with three equivalent Li(2)N3O tetrahedra, corners with three equivalent Li(3)N3O tetrahedra, corners with four equivalent Li(1)N4 tetrahedra, corners with six equivalent Li(4)N4 tetrahedra, edges with three equivalent Li(3)N3O tetrahedra, and edges with three equivalent Li(4)N4 tetrahedra. The Ta(1)-N(2) bond length is 1.97 Å. All Ta(1)-N(1) bond lengths are 1.97 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded in a distorted body-centered cubic geometry to one Li(1), one Li(2), one Li(3), four equivalent Li(4), and one Ta(1) atom. In the second N site, N(2) is bonded in a distorted body-centered cubic geometry to one Li(1), six equivalent Li(3), and one Ta(1) atom. O(1) is bonded in a body-centered cubic geometry to two equivalent Li(2) and six equivalent Li(3) atoms.