Li2NbV3O8 crystallizes in the monoclinic Cm space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), one O(8), and two equivalent O(5) atoms to form LiO5 square pyramids that share  a cornercorner with one V(1)O6 octahedra, corners with two equivalent Li(1)O5 square pyramids, edges with two equivalent V(1)O6 octahedra, edges with two equivalent V(2)O6 octahedra, and  an edgeedge with one Li(2)O5 square pyramid. The corner-sharing octahedral tilt angles are 1°. In the second Li site, Li(2) is bonded to one O(1), one O(7), one O(8), and two equivalent O(4) atoms to form LiO5 square pyramids that share  a cornercorner with one V(2)O6 octahedra, corners with two equivalent Li(2)O5 square pyramids, edges with two equivalent V(1)O6 octahedra, edges with two equivalent V(2)O6 octahedra, and  an edgeedge with one Li(1)O5 square pyramid. The corner-sharing octahedral tilt angles are 6°. Nb(1) is bonded in a 6-coordinate geometry to one O(5), one O(6), one O(7), one O(8), and two equivalent O(2) atoms. There are three inequivalent V sites. In the first V site, V(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(8) atoms to form VO6 octahedra that share corners with two equivalent V(1)O6 octahedra,  a cornercorner with one Li(1)O5 square pyramid,  an edgeedge with one V(2)O6 octahedra, edges with two equivalent Li(1)O5 square pyramids, and edges with two equivalent Li(2)O5 square pyramids. The corner-sharing octahedral tilt angles are 15°. In the second V site, V(2) is bonded to one O(4), one O(5), one O(6), one O(7), and two equivalent O(1) atoms to form VO6 octahedra that share corners with two equivalent V(2)O6 octahedra,  a cornercorner with one Li(2)O5 square pyramid,  an edgeedge with one V(1)O6 octahedra, edges with two equivalent Li(1)O5 square pyramids, and edges with two equivalent Li(2)O5 square pyramids. The corner-sharing octahedral tilt angles are 11°. In the third V site, V(3) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and two equivalent O(7) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one V(3), and two equivalent V(2) atoms to form OLi2V3 square pyramids that share corners with two equivalent O(1)Li2V3 square pyramids,  a cornercorner with one O(4)Li2V3 trigonal bipyramid,  a cornercorner with one O(7)LiNbV3 trigonal bipyramid,  an edgeedge with one O(8)Li2NbV2 square pyramid,  an edgeedge with one O(2)LiNb2V2 trigonal bipyramid, edges with two equivalent O(5)Li2NbV2 trigonal bipyramids, edges with two equivalent O(4)Li2V3 trigonal bipyramids, and edges with two equivalent O(7)LiNbV3 trigonal bipyramids. In the second O site, O(2) is bonded to one Li(1), two equivalent Nb(1), one V(1), and one V(3) atom to form distorted OLiNb2V2 trigonal bipyramids that share  a cornercorner with one O(8)Li2NbV2 square pyramid,  a cornercorner with one O(5)Li2NbV2 trigonal bipyramid, corners with two equivalent O(2)LiNb2V2 trigonal bipyramids,  an edgeedge with one O(1)Li2V3 square pyramid, edges with two equivalent O(8)Li2NbV2 square pyramids,  an edgeedge with one O(4)Li2V3 trigonal bipyramid, edges with two equivalent O(5)Li2NbV2 trigonal bipyramids, and edges with two equivalent O(7)LiNbV3 trigonal bipyramids. In the third O site, O(3) is bonded in a linear geometry to one V(1) and one V(3) atom. In the fourth O site, O(4) is bonded to two equivalent Li(2), one V(1), one V(2), and one V(3) atom to form OLi2V3 trigonal bipyramids that share  a cornercorner with one O(1)Li2V3 square pyramid,  a cornercorner with one O(7)LiNbV3 trigonal bipyramid, corners with two equivalent O(4)Li2V3 trigonal bipyramids, edges with two equivalent O(8)Li2NbV2 square pyramids, edges with two equivalent O(1)Li2V3 square pyramids,  an edgeedge with one O(5)Li2NbV2 trigonal bipyramid,  an edgeedge with one O(2)LiNb2V2 trigonal bipyramid, and edges with two equivalent O(7)LiNbV3 trigonal bipyramids. In the fifth O site, O(5) is bonded to two equivalent Li(1), one Nb(1), one V(1), and one V(2) atom to form OLi2NbV2 trigonal bipyramids that share  a cornercorner with one O(8)Li2NbV2 square pyramid,  a cornercorner with one O(2)LiNb2V2 trigonal bipyramid, corners with two equivalent O(5)Li2NbV2 trigonal bipyramids, edges with two equivalent O(8)Li2NbV2 square pyramids, edges with two equivalent O(1)Li2V3 square pyramids,  an edgeedge with one O(4)Li2V3 trigonal bipyramid,  an edgeedge with one O(7)LiNbV3 trigonal bipyramid, and edges with two equivalent O(2)LiNb2V2 trigonal bipyramids. In the sixth O site, O(6) is bonded in a linear geometry to one Nb(1) and one V(2) atom. In the seventh O site, O(7) is bonded to one Li(2), one Nb(1), one V(2), and two equivalent V(3) atoms to form distorted OLiNbV3 trigonal bipyramids that share  a cornercorner with one O(1)Li2V3 square pyramid,  a cornercorner with one O(4)Li2V3 trigonal bipyramid, corners with two equivalent O(7)LiNbV3 trigonal bipyramids,  an edgeedge with one O(8)Li2NbV2 square pyramid, edges with two equivalent O(1)Li2V3 square pyramids,  an edgeedge with one O(5)Li2NbV2 trigonal bipyramid, edges with two equivalent O(4)Li2V3 trigonal bipyramids, and edges with two equivalent O(2)LiNb2V2 trigonal bipyramids. In the eighth O site, O(8) is bonded to one Li(1), one Li(2), one Nb(1), and two equivalent V(1) atoms to form OLi2NbV2 square pyramids that share corners with two equivalent O(8)Li2NbV2 square pyramids,  a cornercorner with one O(5)Li2NbV2 trigonal bipyramid,  a cornercorner with one O(2)LiNb2V2 trigonal bipyramid,  an edgeedge with one O(1)Li2V3 square pyramid,  an edgeedge with one O(7)LiNbV3 trigonal bipyramid, edges with two equivalent O(5)Li2NbV2 trigonal bipyramids, edges with two equivalent O(4)Li2V3 trigonal bipyramids, and edges with two equivalent O(2)LiNb2V2 trigonal bipyramids.
Li2NbV3O8 crystallizes in the monoclinic Cm space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), one O(8), and two equivalent O(5) atoms to form LiO5 square pyramids that share  a cornercorner with one V(1)O6 octahedra, corners with two equivalent Li(1)O5 square pyramids, edges with two equivalent V(1)O6 octahedra, edges with two equivalent V(2)O6 octahedra, and  an edgeedge with one Li(2)O5 square pyramid. The corner-sharing octahedral tilt angles are 1°. The Li(1)-O(1) bond length is 1.99 Å. The Li(1)-O(2) bond length is 2.12 Å. The Li(1)-O(8) bond length is 2.07 Å. Both Li(1)-O(5) bond lengths are 2.06 Å. In the second Li site, Li(2) is bonded to one O(1), one O(7), one O(8), and two equivalent O(4) atoms to form LiO5 square pyramids that share  a cornercorner with one V(2)O6 octahedra, corners with two equivalent Li(2)O5 square pyramids, edges with two equivalent V(1)O6 octahedra, edges with two equivalent V(2)O6 octahedra, and  an edgeedge with one Li(1)O5 square pyramid. The corner-sharing octahedral tilt angles are 6°. The Li(2)-O(1) bond length is 2.16 Å. The Li(2)-O(7) bond length is 2.09 Å. The Li(2)-O(8) bond length is 2.09 Å. Both Li(2)-O(4) bond lengths are 2.06 Å. Nb(1) is bonded in a 6-coordinate geometry to one O(5), one O(6), one O(7), one O(8), and two equivalent O(2) atoms. The Nb(1)-O(5) bond length is 1.98 Å. The Nb(1)-O(6) bond length is 1.79 Å. The Nb(1)-O(7) bond length is 2.41 Å. The Nb(1)-O(8) bond length is 2.06 Å. Both Nb(1)-O(2) bond lengths are 2.08 Å. There are three inequivalent V sites. In the first V site, V(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(8) atoms to form VO6 octahedra that share corners with two equivalent V(1)O6 octahedra,  a cornercorner with one Li(1)O5 square pyramid,  an edgeedge with one V(2)O6 octahedra, edges with two equivalent Li(1)O5 square pyramids, and edges with two equivalent Li(2)O5 square pyramids. The corner-sharing octahedral tilt angles are 15°. The V(1)-O(2) bond length is 2.15 Å. The V(1)-O(3) bond length is 1.87 Å. The V(1)-O(4) bond length is 2.16 Å. The V(1)-O(5) bond length is 2.05 Å. Both V(1)-O(8) bond lengths are 2.07 Å. In the second V site, V(2) is bonded to one O(4), one O(5), one O(6), one O(7), and two equivalent O(1) atoms to form VO6 octahedra that share corners with two equivalent V(2)O6 octahedra,  a cornercorner with one Li(2)O5 square pyramid,  an edgeedge with one V(1)O6 octahedra, edges with two equivalent Li(1)O5 square pyramids, and edges with two equivalent Li(2)O5 square pyramids. The corner-sharing octahedral tilt angles are 11°. The V(2)-O(4) bond length is 2.00 Å. The V(2)-O(5) bond length is 2.14 Å. The V(2)-O(6) bond length is 2.02 Å. The V(2)-O(7) bond length is 2.07 Å. Both V(2)-O(1) bond lengths are 2.07 Å. In the third V site, V(3) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and two equivalent O(7) atoms. The V(3)-O(1) bond length is 2.07 Å. The V(3)-O(2) bond length is 2.54 Å. The V(3)-O(3) bond length is 1.80 Å. The V(3)-O(4) bond length is 2.06 Å. Both V(3)-O(7) bond lengths are 2.11 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one V(3), and two equivalent V(2) atoms to form OLi2V3 square pyramids that share corners with two equivalent O(1)Li2V3 square pyramids,  a cornercorner with one O(4)Li2V3 trigonal bipyramid,  a cornercorner with one O(7)LiNbV3 trigonal bipyramid,  an edgeedge with one O(8)Li2NbV2 square pyramid,  an edgeedge with one O(2)LiNb2V2 trigonal bipyramid, edges with two equivalent O(5)Li2NbV2 trigonal bipyramids, edges with two equivalent O(4)Li2V3 trigonal bipyramids, and edges with two equivalent O(7)LiNbV3 trigonal bipyramids. In the second O site, O(2) is bonded to one Li(1), two equivalent Nb(1), one V(1), and one V(3) atom to form distorted OLiNb2V2 trigonal bipyramids that share  a cornercorner with one O(8)Li2NbV2 square pyramid,  a cornercorner with one O(5)Li2NbV2 trigonal bipyramid, corners with two equivalent O(2)LiNb2V2 trigonal bipyramids,  an edgeedge with one O(1)Li2V3 square pyramid, edges with two equivalent O(8)Li2NbV2 square pyramids,  an edgeedge with one O(4)Li2V3 trigonal bipyramid, edges with two equivalent O(5)Li2NbV2 trigonal bipyramids, and edges with two equivalent O(7)LiNbV3 trigonal bipyramids. In the third O site, O(3) is bonded in a linear geometry to one V(1) and one V(3) atom. In the fourth O site, O(4) is bonded to two equivalent Li(2), one V(1), one V(2), and one V(3) atom to form OLi2V3 trigonal bipyramids that share  a cornercorner with one O(1)Li2V3 square pyramid,  a cornercorner with one O(7)LiNbV3 trigonal bipyramid, corners with two equivalent O(4)Li2V3 trigonal bipyramids, edges with two equivalent O(8)Li2NbV2 square pyramids, edges with two equivalent O(1)Li2V3 square pyramids,  an edgeedge with one O(5)Li2NbV2 trigonal bipyramid,  an edgeedge with one O(2)LiNb2V2 trigonal bipyramid, and edges with two equivalent O(7)LiNbV3 trigonal bipyramids. In the fifth O site, O(5) is bonded to two equivalent Li(1), one Nb(1), one V(1), and one V(2) atom to form OLi2NbV2 trigonal bipyramids that share  a cornercorner with one O(8)Li2NbV2 square pyramid,  a cornercorner with one O(2)LiNb2V2 trigonal bipyramid, corners with two equivalent O(5)Li2NbV2 trigonal bipyramids, edges with two equivalent O(8)Li2NbV2 square pyramids, edges with two equivalent O(1)Li2V3 square pyramids,  an edgeedge with one O(4)Li2V3 trigonal bipyramid,  an edgeedge with one O(7)LiNbV3 trigonal bipyramid, and edges with two equivalent O(2)LiNb2V2 trigonal bipyramids. In the sixth O site, O(6) is bonded in a linear geometry to one Nb(1) and one V(2) atom. In the seventh O site, O(7) is bonded to one Li(2), one Nb(1), one V(2), and two equivalent V(3) atoms to form distorted OLiNbV3 trigonal bipyramids that share  a cornercorner with one O(1)Li2V3 square pyramid,  a cornercorner with one O(4)Li2V3 trigonal bipyramid, corners with two equivalent O(7)LiNbV3 trigonal bipyramids,  an edgeedge with one O(8)Li2NbV2 square pyramid, edges with two equivalent O(1)Li2V3 square pyramids,  an edgeedge with one O(5)Li2NbV2 trigonal bipyramid, edges with two equivalent O(4)Li2V3 trigonal bipyramids, and edges with two equivalent O(2)LiNb2V2 trigonal bipyramids. In the eighth O site, O(8) is bonded to one Li(1), one Li(2), one Nb(1), and two equivalent V(1) atoms to form OLi2NbV2 square pyramids that share corners with two equivalent O(8)Li2NbV2 square pyramids,  a cornercorner with one O(5)Li2NbV2 trigonal bipyramid,  a cornercorner with one O(2)LiNb2V2 trigonal bipyramid,  an edgeedge with one O(1)Li2V3 square pyramid,  an edgeedge with one O(7)LiNbV3 trigonal bipyramid, edges with two equivalent O(5)Li2NbV2 trigonal bipyramids, edges with two equivalent O(4)Li2V3 trigonal bipyramids, and edges with two equivalent O(2)LiNb2V2 trigonal bipyramids.