Lu2TiO5 crystallizes in the orthorhombic Cmcm space group. Lu(1) is bonded to one O(3), two equivalent O(1), and three equivalent O(2) atoms to form distorted LuO6 pentagonal pyramids that share  a cornercorner with one Ti(1)O6 octahedra, corners with three equivalent Lu(1)O6 pentagonal pyramids, edges with three equivalent Ti(1)O6 octahedra, and edges with three equivalent Lu(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 29°. Ti(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Lu(1)O6 pentagonal pyramids, and edges with six equivalent Lu(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 34°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Lu(1) and one Ti(1) atom. In the second O site, O(2) is bonded to three equivalent Lu(1) and one Ti(1) atom to form OLu3Ti trigonal pyramids that share  a cornercorner with one O(3)Lu2Ti2 tetrahedra, corners with three equivalent O(2)Lu3Ti trigonal pyramids, edges with two equivalent O(3)Lu2Ti2 tetrahedra, and edges with two equivalent O(2)Lu3Ti trigonal pyramids. In the third O site, O(3) is bonded to two equivalent Lu(1) and two equivalent Ti(1) atoms to form distorted OLu2Ti2 tetrahedra that share corners with two equivalent O(3)Lu2Ti2 tetrahedra, corners with two equivalent O(2)Lu3Ti trigonal pyramids, and edges with four equivalent O(2)Lu3Ti trigonal pyramids.
Lu2TiO5 crystallizes in the orthorhombic Cmcm space group. Lu(1) is bonded to one O(3), two equivalent O(1), and three equivalent O(2) atoms to form distorted LuO6 pentagonal pyramids that share  a cornercorner with one Ti(1)O6 octahedra, corners with three equivalent Lu(1)O6 pentagonal pyramids, edges with three equivalent Ti(1)O6 octahedra, and edges with three equivalent Lu(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 29°. The Lu(1)-O(3) bond length is 2.31 Å. There is one shorter (2.16 Å) and one longer (2.21 Å) Lu(1)-O(1) bond length. There are two shorter (2.14 Å) and one longer (2.30 Å) Lu(1)-O(2) bond length. Ti(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Lu(1)O6 pentagonal pyramids, and edges with six equivalent Lu(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 34°. Both Ti(1)-O(1) bond lengths are 1.88 Å. Both Ti(1)-O(2) bond lengths are 2.11 Å. Both Ti(1)-O(3) bond lengths are 2.11 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Lu(1) and one Ti(1) atom. In the second O site, O(2) is bonded to three equivalent Lu(1) and one Ti(1) atom to form OLu3Ti trigonal pyramids that share  a cornercorner with one O(3)Lu2Ti2 tetrahedra, corners with three equivalent O(2)Lu3Ti trigonal pyramids, edges with two equivalent O(3)Lu2Ti2 tetrahedra, and edges with two equivalent O(2)Lu3Ti trigonal pyramids. In the third O site, O(3) is bonded to two equivalent Lu(1) and two equivalent Ti(1) atoms to form distorted OLu2Ti2 tetrahedra that share corners with two equivalent O(3)Lu2Ti2 tetrahedra, corners with two equivalent O(2)Lu3Ti trigonal pyramids, and edges with four equivalent O(2)Lu3Ti trigonal pyramids.