Li2Nb4O11 crystallizes in the monoclinic C2/c space group. Li(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form distorted LiO4 trigonal pyramids that share corners with three equivalent Nb(2)O6 octahedra and  an edgeedge with one Nb(3)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 55-56°. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(6), and two equivalent O(4) atoms. In the second Nb site, Nb(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form NbO6 octahedra that share corners with two equivalent Nb(3)O7 pentagonal bipyramids and corners with six equivalent Li(1)O4 trigonal pyramids. In the third Nb site, Nb(3) is bonded to one O(6), two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form distorted NbO7 pentagonal bipyramids that share corners with two equivalent Nb(2)O6 octahedra and edges with two equivalent Li(1)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 45°. There are six inequivalent O sites. In the first O site, O(6) is bonded in a 3-coordinate geometry to one Nb(3) and two equivalent Nb(1) atoms. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Nb(1) and one Nb(3) atom. In the third O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1), one Nb(1), and one Nb(2) atom. In the fourth O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1), one Nb(1), and one Nb(2) atom. In the fifth O site, O(4) is bonded to one Li(1), one Nb(3), and two equivalent Nb(1) atoms to form corner-sharing OLiNb3 tetrahedra. In the sixth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Nb(2), and one Nb(3) atom.
Li2Nb4O11 crystallizes in the monoclinic C2/c space group. Li(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form distorted LiO4 trigonal pyramids that share corners with three equivalent Nb(2)O6 octahedra and  an edgeedge with one Nb(3)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 55-56°. The Li(1)-O(2) bond length is 2.17 Å. The Li(1)-O(3) bond length is 2.17 Å. The Li(1)-O(4) bond length is 1.98 Å. The Li(1)-O(5) bond length is 2.24 Å. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(6), and two equivalent O(4) atoms. The Nb(1)-O(1) bond length is 1.97 Å. The Nb(1)-O(2) bond length is 1.99 Å. The Nb(1)-O(3) bond length is 1.99 Å. The Nb(1)-O(6) bond length is 2.02 Å. Both Nb(1)-O(4) bond lengths are 2.08 Å. In the second Nb site, Nb(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form NbO6 octahedra that share corners with two equivalent Nb(3)O7 pentagonal bipyramids and corners with six equivalent Li(1)O4 trigonal pyramids. Both Nb(2)-O(2) bond lengths are 2.02 Å. Both Nb(2)-O(3) bond lengths are 2.02 Å. Both Nb(2)-O(5) bond lengths are 2.02 Å. In the third Nb site, Nb(3) is bonded to one O(6), two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form distorted NbO7 pentagonal bipyramids that share corners with two equivalent Nb(2)O6 octahedra and edges with two equivalent Li(1)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 45°. The Nb(3)-O(6) bond length is 2.42 Å. Both Nb(3)-O(1) bond lengths are 2.02 Å. Both Nb(3)-O(4) bond lengths are 2.07 Å. Both Nb(3)-O(5) bond lengths are 1.99 Å. There are six inequivalent O sites. In the first O site, O(6) is bonded in a 3-coordinate geometry to one Nb(3) and two equivalent Nb(1) atoms. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Nb(1) and one Nb(3) atom. In the third O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1), one Nb(1), and one Nb(2) atom. In the fourth O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1), one Nb(1), and one Nb(2) atom. In the fifth O site, O(4) is bonded to one Li(1), one Nb(3), and two equivalent Nb(1) atoms to form corner-sharing OLiNb3 tetrahedra. In the sixth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Nb(2), and one Nb(3) atom.