LiMnNbO4 is Spinel-derived structured and crystallizes in the orthorhombic P222_1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted LiO6 octahedra that share corners with six equivalent Mn(1)O4 tetrahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Nb(1)O6 octahedra, and edges with two equivalent Nb(2)O6 octahedra. In the second Li site, Li(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form distorted LiO6 octahedra that share corners with six equivalent Mn(1)O4 tetrahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Nb(1)O6 octahedra, and edges with two equivalent Nb(2)O6 octahedra. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted NbO6 octahedra that share corners with six equivalent Mn(1)O4 tetrahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, and edges with two equivalent Nb(2)O6 octahedra. In the second Nb site, Nb(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted NbO6 octahedra that share corners with six equivalent Mn(1)O4 tetrahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, and edges with two equivalent Nb(1)O6 octahedra. Mn(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form MnO4 tetrahedra that share corners with three equivalent Li(1)O6 octahedra, corners with three equivalent Li(2)O6 octahedra, corners with three equivalent Nb(1)O6 octahedra, and corners with three equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-64°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Nb(1), and one Mn(1) atom to form distorted OLi2MnNb trigonal pyramids that share corners with three equivalent O(1)Li2MnNb trigonal pyramids, corners with three equivalent O(2)Li2MnNb trigonal pyramids, corners with three equivalent O(3)LiMnNb2 trigonal pyramids, corners with three equivalent O(4)LiMnNb2 trigonal pyramids,  an edgeedge with one O(2)Li2MnNb trigonal pyramid,  an edgeedge with one O(3)LiMnNb2 trigonal pyramid, and  an edgeedge with one O(4)LiMnNb2 trigonal pyramid. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Nb(2), and one Mn(1) atom to form distorted OLi2MnNb trigonal pyramids that share corners with three equivalent O(1)Li2MnNb trigonal pyramids, corners with three equivalent O(2)Li2MnNb trigonal pyramids, corners with three equivalent O(3)LiMnNb2 trigonal pyramids, corners with three equivalent O(4)LiMnNb2 trigonal pyramids,  an edgeedge with one O(1)Li2MnNb trigonal pyramid,  an edgeedge with one O(3)LiMnNb2 trigonal pyramid, and  an edgeedge with one O(4)LiMnNb2 trigonal pyramid. In the third O site, O(3) is bonded to one Li(1), one Nb(1), one Nb(2), and one Mn(1) atom to form distorted OLiMnNb2 trigonal pyramids that share corners with three equivalent O(1)Li2MnNb trigonal pyramids, corners with three equivalent O(2)Li2MnNb trigonal pyramids, corners with three equivalent O(3)LiMnNb2 trigonal pyramids, corners with three equivalent O(4)LiMnNb2 trigonal pyramids,  an edgeedge with one O(1)Li2MnNb trigonal pyramid,  an edgeedge with one O(2)Li2MnNb trigonal pyramid, and  an edgeedge with one O(4)LiMnNb2 trigonal pyramid. In the fourth O site, O(4) is bonded to one Li(2), one Nb(1), one Nb(2), and one Mn(1) atom to form distorted OLiMnNb2 trigonal pyramids that share corners with three equivalent O(1)Li2MnNb trigonal pyramids, corners with three equivalent O(2)Li2MnNb trigonal pyramids, corners with three equivalent O(3)LiMnNb2 trigonal pyramids, corners with three equivalent O(4)LiMnNb2 trigonal pyramids,  an edgeedge with one O(1)Li2MnNb trigonal pyramid,  an edgeedge with one O(2)Li2MnNb trigonal pyramid, and  an edgeedge with one O(3)LiMnNb2 trigonal pyramid.
LiMnNbO4 is Spinel-derived structured and crystallizes in the orthorhombic P222_1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted LiO6 octahedra that share corners with six equivalent Mn(1)O4 tetrahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Nb(1)O6 octahedra, and edges with two equivalent Nb(2)O6 octahedra. Both Li(1)-O(1) bond lengths are 2.21 Å. Both Li(1)-O(2) bond lengths are 2.07 Å. Both Li(1)-O(3) bond lengths are 2.35 Å. In the second Li site, Li(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form distorted LiO6 octahedra that share corners with six equivalent Mn(1)O4 tetrahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Nb(1)O6 octahedra, and edges with two equivalent Nb(2)O6 octahedra. Both Li(2)-O(1) bond lengths are 2.07 Å. Both Li(2)-O(2) bond lengths are 2.21 Å. Both Li(2)-O(4) bond lengths are 2.36 Å. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted NbO6 octahedra that share corners with six equivalent Mn(1)O4 tetrahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, and edges with two equivalent Nb(2)O6 octahedra. Both Nb(1)-O(1) bond lengths are 1.91 Å. Both Nb(1)-O(3) bond lengths are 2.02 Å. Both Nb(1)-O(4) bond lengths are 2.21 Å. In the second Nb site, Nb(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted NbO6 octahedra that share corners with six equivalent Mn(1)O4 tetrahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, and edges with two equivalent Nb(1)O6 octahedra. Both Nb(2)-O(2) bond lengths are 1.91 Å. Both Nb(2)-O(3) bond lengths are 2.21 Å. Both Nb(2)-O(4) bond lengths are 2.02 Å. Mn(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form MnO4 tetrahedra that share corners with three equivalent Li(1)O6 octahedra, corners with three equivalent Li(2)O6 octahedra, corners with three equivalent Nb(1)O6 octahedra, and corners with three equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-64°. The Mn(1)-O(1) bond length is 2.07 Å. The Mn(1)-O(2) bond length is 2.06 Å. The Mn(1)-O(3) bond length is 2.07 Å. The Mn(1)-O(4) bond length is 2.07 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Nb(1), and one Mn(1) atom to form distorted OLi2MnNb trigonal pyramids that share corners with three equivalent O(1)Li2MnNb trigonal pyramids, corners with three equivalent O(2)Li2MnNb trigonal pyramids, corners with three equivalent O(3)LiMnNb2 trigonal pyramids, corners with three equivalent O(4)LiMnNb2 trigonal pyramids,  an edgeedge with one O(2)Li2MnNb trigonal pyramid,  an edgeedge with one O(3)LiMnNb2 trigonal pyramid, and  an edgeedge with one O(4)LiMnNb2 trigonal pyramid. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Nb(2), and one Mn(1) atom to form distorted OLi2MnNb trigonal pyramids that share corners with three equivalent O(1)Li2MnNb trigonal pyramids, corners with three equivalent O(2)Li2MnNb trigonal pyramids, corners with three equivalent O(3)LiMnNb2 trigonal pyramids, corners with three equivalent O(4)LiMnNb2 trigonal pyramids,  an edgeedge with one O(1)Li2MnNb trigonal pyramid,  an edgeedge with one O(3)LiMnNb2 trigonal pyramid, and  an edgeedge with one O(4)LiMnNb2 trigonal pyramid. In the third O site, O(3) is bonded to one Li(1), one Nb(1), one Nb(2), and one Mn(1) atom to form distorted OLiMnNb2 trigonal pyramids that share corners with three equivalent O(1)Li2MnNb trigonal pyramids, corners with three equivalent O(2)Li2MnNb trigonal pyramids, corners with three equivalent O(3)LiMnNb2 trigonal pyramids, corners with three equivalent O(4)LiMnNb2 trigonal pyramids,  an edgeedge with one O(1)Li2MnNb trigonal pyramid,  an edgeedge with one O(2)Li2MnNb trigonal pyramid, and  an edgeedge with one O(4)LiMnNb2 trigonal pyramid. In the fourth O site, O(4) is bonded to one Li(2), one Nb(1), one Nb(2), and one Mn(1) atom to form distorted OLiMnNb2 trigonal pyramids that share corners with three equivalent O(1)Li2MnNb trigonal pyramids, corners with three equivalent O(2)Li2MnNb trigonal pyramids, corners with three equivalent O(3)LiMnNb2 trigonal pyramids, corners with three equivalent O(4)LiMnNb2 trigonal pyramids,  an edgeedge with one O(1)Li2MnNb trigonal pyramid,  an edgeedge with one O(2)Li2MnNb trigonal pyramid, and  an edgeedge with one O(3)LiMnNb2 trigonal pyramid.