Li2NbNi3O8 is Spinel-derived structured and crystallizes in the hexagonal P6_3mc space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(3) and three equivalent O(2) atoms to form LiO4 tetrahedra that share corners with three equivalent Nb(1)O6 octahedra and corners with nine equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 59-61°. In the second Li site, Li(2) is bonded to one O(4) and three equivalent O(1) atoms to form distorted LiO4 tetrahedra that share corners with three equivalent Nb(1)O6 octahedra, corners with three equivalent Ni(1)O6 octahedra, and edges with three equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-64°. Nb(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NbO6 octahedra that share corners with six equivalent Ni(1)O6 octahedra, corners with three equivalent Li(1)O4 tetrahedra, corners with three equivalent Li(2)O4 tetrahedra, and edges with three equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 52°. Ni(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form NiO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra,  a cornercorner with one Li(2)O4 tetrahedra, corners with three equivalent Li(1)O4 tetrahedra,  an edgeedge with one Nb(1)O6 octahedra, edges with four equivalent Ni(1)O6 octahedra, and  an edgeedge with one Li(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Li(2), one Nb(1), and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded to one Li(1), one Nb(1), and two equivalent Ni(1) atoms to form distorted OLiNbNi2 tetrahedra that share  a cornercorner with one O(3)LiNi3 tetrahedra, corners with two equivalent O(2)LiNbNi2 tetrahedra, corners with two equivalent O(4)LiNi3 tetrahedra,  an edgeedge with one O(3)LiNi3 tetrahedra, and edges with two equivalent O(2)LiNbNi2 tetrahedra. In the third O site, O(3) is bonded to one Li(1) and three equivalent Ni(1) atoms to form OLiNi3 tetrahedra that share corners with three equivalent O(2)LiNbNi2 tetrahedra, corners with three equivalent O(4)LiNi3 tetrahedra, and edges with three equivalent O(2)LiNbNi2 tetrahedra. In the fourth O site, O(4) is bonded to one Li(2) and three equivalent Ni(1) atoms to form OLiNi3 tetrahedra that share corners with three equivalent O(3)LiNi3 tetrahedra and corners with six equivalent O(2)LiNbNi2 tetrahedra.
Li2NbNi3O8 is Spinel-derived structured and crystallizes in the hexagonal P6_3mc space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(3) and three equivalent O(2) atoms to form LiO4 tetrahedra that share corners with three equivalent Nb(1)O6 octahedra and corners with nine equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 59-61°. The Li(1)-O(3) bond length is 2.16 Å. All Li(1)-O(2) bond lengths are 1.93 Å. In the second Li site, Li(2) is bonded to one O(4) and three equivalent O(1) atoms to form distorted LiO4 tetrahedra that share corners with three equivalent Nb(1)O6 octahedra, corners with three equivalent Ni(1)O6 octahedra, and edges with three equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-64°. The Li(2)-O(4) bond length is 1.83 Å. All Li(2)-O(1) bond lengths are 1.93 Å. Nb(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NbO6 octahedra that share corners with six equivalent Ni(1)O6 octahedra, corners with three equivalent Li(1)O4 tetrahedra, corners with three equivalent Li(2)O4 tetrahedra, and edges with three equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 52°. All Nb(1)-O(1) bond lengths are 1.96 Å. All Nb(1)-O(2) bond lengths are 2.12 Å. Ni(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form NiO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra,  a cornercorner with one Li(2)O4 tetrahedra, corners with three equivalent Li(1)O4 tetrahedra,  an edgeedge with one Nb(1)O6 octahedra, edges with four equivalent Ni(1)O6 octahedra, and  an edgeedge with one Li(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. The Ni(1)-O(3) bond length is 1.92 Å. The Ni(1)-O(4) bond length is 1.91 Å. Both Ni(1)-O(1) bond lengths are 2.06 Å. Both Ni(1)-O(2) bond lengths are 2.02 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Li(2), one Nb(1), and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded to one Li(1), one Nb(1), and two equivalent Ni(1) atoms to form distorted OLiNbNi2 tetrahedra that share  a cornercorner with one O(3)LiNi3 tetrahedra, corners with two equivalent O(2)LiNbNi2 tetrahedra, corners with two equivalent O(4)LiNi3 tetrahedra,  an edgeedge with one O(3)LiNi3 tetrahedra, and edges with two equivalent O(2)LiNbNi2 tetrahedra. In the third O site, O(3) is bonded to one Li(1) and three equivalent Ni(1) atoms to form OLiNi3 tetrahedra that share corners with three equivalent O(2)LiNbNi2 tetrahedra, corners with three equivalent O(4)LiNi3 tetrahedra, and edges with three equivalent O(2)LiNbNi2 tetrahedra. In the fourth O site, O(4) is bonded to one Li(2) and three equivalent Ni(1) atoms to form OLiNi3 tetrahedra that share corners with three equivalent O(3)LiNi3 tetrahedra and corners with six equivalent O(2)LiNbNi2 tetrahedra.