Lu3NbO7 crystallizes in the orthorhombic Cmme space group. There are two inequivalent Lu sites. In the first Lu site, Lu(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted corner-sharing LuO6 octahedra. The corner-sharing octahedral tilt angles are 69°. In the second Lu site, Lu(2) is bonded in a 7-coordinate geometry to one O(1), two equivalent O(3), and four equivalent O(2) atoms. Nb(1) is bonded in a body-centered cubic geometry to four equivalent O(2) and four equivalent O(3) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Lu(1) and two equivalent Lu(2) atoms to form OLu4 tetrahedra that share corners with two equivalent O(1)Lu4 tetrahedra, corners with four equivalent O(3)Lu2Nb2 tetrahedra, corners with eight equivalent O(2)Lu3Nb tetrahedra, and edges with four equivalent O(2)Lu3Nb tetrahedra. In the second O site, O(2) is bonded to one Lu(1), two equivalent Lu(2), and one Nb(1) atom to form OLu3Nb tetrahedra that share corners with two equivalent O(1)Lu4 tetrahedra, corners with four equivalent O(3)Lu2Nb2 tetrahedra, corners with eight equivalent O(2)Lu3Nb tetrahedra,  an edgeedge with one O(1)Lu4 tetrahedra, edges with two equivalent O(3)Lu2Nb2 tetrahedra, and edges with two equivalent O(2)Lu3Nb tetrahedra. In the third O site, O(3) is bonded to two equivalent Lu(2) and two equivalent Nb(1) atoms to form distorted OLu2Nb2 tetrahedra that share corners with two equivalent O(1)Lu4 tetrahedra, corners with four equivalent O(3)Lu2Nb2 tetrahedra, corners with eight equivalent O(2)Lu3Nb tetrahedra, edges with two equivalent O(3)Lu2Nb2 tetrahedra, and edges with four equivalent O(2)Lu3Nb tetrahedra.
Lu3NbO7 crystallizes in the orthorhombic Cmme space group. There are two inequivalent Lu sites. In the first Lu site, Lu(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted corner-sharing LuO6 octahedra. The corner-sharing octahedral tilt angles are 69°. Both Lu(1)-O(1) bond lengths are 2.23 Å. All Lu(1)-O(2) bond lengths are 2.21 Å. In the second Lu site, Lu(2) is bonded in a 7-coordinate geometry to one O(1), two equivalent O(3), and four equivalent O(2) atoms. The Lu(2)-O(1) bond length is 2.18 Å. There is one shorter (2.04 Å) and one longer (2.54 Å) Lu(2)-O(3) bond length. There are two shorter (2.19 Å) and two longer (2.42 Å) Lu(2)-O(2) bond lengths. Nb(1) is bonded in a body-centered cubic geometry to four equivalent O(2) and four equivalent O(3) atoms. All Nb(1)-O(2) bond lengths are 2.19 Å. All Nb(1)-O(3) bond lengths are 2.17 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Lu(1) and two equivalent Lu(2) atoms to form OLu4 tetrahedra that share corners with two equivalent O(1)Lu4 tetrahedra, corners with four equivalent O(3)Lu2Nb2 tetrahedra, corners with eight equivalent O(2)Lu3Nb tetrahedra, and edges with four equivalent O(2)Lu3Nb tetrahedra. In the second O site, O(2) is bonded to one Lu(1), two equivalent Lu(2), and one Nb(1) atom to form OLu3Nb tetrahedra that share corners with two equivalent O(1)Lu4 tetrahedra, corners with four equivalent O(3)Lu2Nb2 tetrahedra, corners with eight equivalent O(2)Lu3Nb tetrahedra,  an edgeedge with one O(1)Lu4 tetrahedra, edges with two equivalent O(3)Lu2Nb2 tetrahedra, and edges with two equivalent O(2)Lu3Nb tetrahedra. In the third O site, O(3) is bonded to two equivalent Lu(2) and two equivalent Nb(1) atoms to form distorted OLu2Nb2 tetrahedra that share corners with two equivalent O(1)Lu4 tetrahedra, corners with four equivalent O(3)Lu2Nb2 tetrahedra, corners with eight equivalent O(2)Lu3Nb tetrahedra, edges with two equivalent O(3)Lu2Nb2 tetrahedra, and edges with four equivalent O(2)Lu3Nb tetrahedra.