Li6NiO4 crystallizes in the monoclinic P2 space group. There are eight inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form LiO4 tetrahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Li(7)O4 tetrahedra, corners with four equivalent Li(8)O4 tetrahedra, edges with two equivalent Li(2)O4 tetrahedra, edges with two equivalent Li(5)O4 tetrahedra, and edges with two equivalent Li(6)O4 tetrahedra. In the second Li site, Li(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form LiO4 tetrahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Li(5)O4 tetrahedra, corners with four equivalent Li(6)O4 tetrahedra, edges with two equivalent Li(1)O4 tetrahedra, edges with two equivalent Li(7)O4 tetrahedra, and edges with two equivalent Li(8)O4 tetrahedra. In the third Li site, Li(3) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form LiO4 tetrahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Li(5)O4 tetrahedra, corners with four equivalent Li(6)O4 tetrahedra, edges with two equivalent Li(4)O4 tetrahedra, edges with two equivalent Li(7)O4 tetrahedra, and edges with two equivalent Li(8)O4 tetrahedra. In the fourth Li site, Li(4) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form LiO4 tetrahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Li(7)O4 tetrahedra, corners with four equivalent Li(8)O4 tetrahedra, edges with two equivalent Li(3)O4 tetrahedra, edges with two equivalent Li(5)O4 tetrahedra, and edges with two equivalent Li(6)O4 tetrahedra. In the fifth Li site, Li(5) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Li(6)O4 tetrahedra, corners with four equivalent Li(8)O4 tetrahedra,  an edgeedge with one Li(1)O4 tetrahedra,  an edgeedge with one Li(4)O4 tetrahedra,  an edgeedge with one Ni(1)O4 tetrahedra, and edges with two equivalent Li(7)O4 tetrahedra. In the sixth Li site, Li(6) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Li(5)O4 tetrahedra, corners with four equivalent Li(7)O4 tetrahedra,  an edgeedge with one Li(1)O4 tetrahedra,  an edgeedge with one Li(4)O4 tetrahedra,  an edgeedge with one Ni(1)O4 tetrahedra, and edges with two equivalent Li(8)O4 tetrahedra. In the seventh Li site, Li(7) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Li(6)O4 tetrahedra, corners with four equivalent Li(8)O4 tetrahedra,  an edgeedge with one Li(2)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra,  an edgeedge with one Ni(2)O4 tetrahedra, and edges with two equivalent Li(5)O4 tetrahedra. In the eighth Li site, Li(8) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Li(5)O4 tetrahedra, corners with four equivalent Li(7)O4 tetrahedra,  an edgeedge with one Li(2)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra,  an edgeedge with one Ni(2)O4 tetrahedra, and edges with two equivalent Li(6)O4 tetrahedra. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form NiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with four equivalent Li(7)O4 tetrahedra, corners with four equivalent Li(8)O4 tetrahedra, edges with two equivalent Li(5)O4 tetrahedra, and edges with two equivalent Li(6)O4 tetrahedra. In the second Ni site, Ni(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form NiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with four equivalent Li(5)O4 tetrahedra, corners with four equivalent Li(6)O4 tetrahedra, edges with two equivalent Li(7)O4 tetrahedra, and edges with two equivalent Li(8)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Li(5), one Li(6), one Li(7), one Li(8), and one Ni(1) atom to form a mixture of distorted corner and edge-sharing OLi6Ni pentagonal bipyramids. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Li(5), one Li(6), one Li(7), one Li(8), and one Ni(2) atom to form a mixture of distorted corner and edge-sharing OLi6Ni pentagonal bipyramids. In the third O site, O(3) is bonded to one Li(3), one Li(4), one Li(5), one Li(6), one Li(7), one Li(8), and one Ni(2) atom to form a mixture of distorted corner and edge-sharing OLi6Ni pentagonal bipyramids. In the fourth O site, O(4) is bonded to one Li(3), one Li(4), one Li(5), one Li(6), one Li(7), one Li(8), and one Ni(1) atom to form a mixture of distorted corner and edge-sharing OLi6Ni pentagonal bipyramids.
Li6NiO4 crystallizes in the monoclinic P2 space group. There are eight inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form LiO4 tetrahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Li(7)O4 tetrahedra, corners with four equivalent Li(8)O4 tetrahedra, edges with two equivalent Li(2)O4 tetrahedra, edges with two equivalent Li(5)O4 tetrahedra, and edges with two equivalent Li(6)O4 tetrahedra. Both Li(1)-O(1) bond lengths are 2.00 Å. Both Li(1)-O(2) bond lengths are 1.93 Å. In the second Li site, Li(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form LiO4 tetrahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Li(5)O4 tetrahedra, corners with four equivalent Li(6)O4 tetrahedra, edges with two equivalent Li(1)O4 tetrahedra, edges with two equivalent Li(7)O4 tetrahedra, and edges with two equivalent Li(8)O4 tetrahedra. Both Li(2)-O(1) bond lengths are 1.93 Å. Both Li(2)-O(2) bond lengths are 2.00 Å. In the third Li site, Li(3) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form LiO4 tetrahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Li(5)O4 tetrahedra, corners with four equivalent Li(6)O4 tetrahedra, edges with two equivalent Li(4)O4 tetrahedra, edges with two equivalent Li(7)O4 tetrahedra, and edges with two equivalent Li(8)O4 tetrahedra. Both Li(3)-O(3) bond lengths are 1.97 Å. Both Li(3)-O(4) bond lengths are 1.90 Å. In the fourth Li site, Li(4) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form LiO4 tetrahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Li(7)O4 tetrahedra, corners with four equivalent Li(8)O4 tetrahedra, edges with two equivalent Li(3)O4 tetrahedra, edges with two equivalent Li(5)O4 tetrahedra, and edges with two equivalent Li(6)O4 tetrahedra. Both Li(4)-O(3) bond lengths are 1.90 Å. Both Li(4)-O(4) bond lengths are 1.96 Å. In the fifth Li site, Li(5) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Li(6)O4 tetrahedra, corners with four equivalent Li(8)O4 tetrahedra,  an edgeedge with one Li(1)O4 tetrahedra,  an edgeedge with one Li(4)O4 tetrahedra,  an edgeedge with one Ni(1)O4 tetrahedra, and edges with two equivalent Li(7)O4 tetrahedra. The Li(5)-O(1) bond length is 2.12 Å. The Li(5)-O(2) bond length is 1.99 Å. The Li(5)-O(3) bond length is 2.00 Å. The Li(5)-O(4) bond length is 2.09 Å. In the sixth Li site, Li(6) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Li(5)O4 tetrahedra, corners with four equivalent Li(7)O4 tetrahedra,  an edgeedge with one Li(1)O4 tetrahedra,  an edgeedge with one Li(4)O4 tetrahedra,  an edgeedge with one Ni(1)O4 tetrahedra, and edges with two equivalent Li(8)O4 tetrahedra. The Li(6)-O(1) bond length is 2.12 Å. The Li(6)-O(2) bond length is 1.99 Å. The Li(6)-O(3) bond length is 2.00 Å. The Li(6)-O(4) bond length is 2.09 Å. In the seventh Li site, Li(7) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Li(6)O4 tetrahedra, corners with four equivalent Li(8)O4 tetrahedra,  an edgeedge with one Li(2)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra,  an edgeedge with one Ni(2)O4 tetrahedra, and edges with two equivalent Li(5)O4 tetrahedra. The Li(7)-O(1) bond length is 1.99 Å. The Li(7)-O(2) bond length is 2.12 Å. The Li(7)-O(3) bond length is 2.09 Å. The Li(7)-O(4) bond length is 2.00 Å. In the eighth Li site, Li(8) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Li(5)O4 tetrahedra, corners with four equivalent Li(7)O4 tetrahedra,  an edgeedge with one Li(2)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra,  an edgeedge with one Ni(2)O4 tetrahedra, and edges with two equivalent Li(6)O4 tetrahedra. The Li(8)-O(1) bond length is 1.99 Å. The Li(8)-O(2) bond length is 2.12 Å. The Li(8)-O(3) bond length is 2.10 Å. The Li(8)-O(4) bond length is 2.00 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form NiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with four equivalent Li(7)O4 tetrahedra, corners with four equivalent Li(8)O4 tetrahedra, edges with two equivalent Li(5)O4 tetrahedra, and edges with two equivalent Li(6)O4 tetrahedra. Both Ni(1)-O(1) bond lengths are 2.01 Å. Both Ni(1)-O(4) bond lengths are 1.99 Å. In the second Ni site, Ni(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form NiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with four equivalent Li(5)O4 tetrahedra, corners with four equivalent Li(6)O4 tetrahedra, edges with two equivalent Li(7)O4 tetrahedra, and edges with two equivalent Li(8)O4 tetrahedra. Both Ni(2)-O(2) bond lengths are 2.01 Å. Both Ni(2)-O(3) bond lengths are 1.99 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Li(5), one Li(6), one Li(7), one Li(8), and one Ni(1) atom to form a mixture of distorted corner and edge-sharing OLi6Ni pentagonal bipyramids. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Li(5), one Li(6), one Li(7), one Li(8), and one Ni(2) atom to form a mixture of distorted corner and edge-sharing OLi6Ni pentagonal bipyramids. In the third O site, O(3) is bonded to one Li(3), one Li(4), one Li(5), one Li(6), one Li(7), one Li(8), and one Ni(2) atom to form a mixture of distorted corner and edge-sharing OLi6Ni pentagonal bipyramids. In the fourth O site, O(4) is bonded to one Li(3), one Li(4), one Li(5), one Li(6), one Li(7), one Li(8), and one Ni(1) atom to form a mixture of distorted corner and edge-sharing OLi6Ni pentagonal bipyramids.