Lu2TiO5 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Lu sites. In the first Lu site, Lu(1) is bonded to one O(1), one O(3), one O(4), two equivalent O(2), and two equivalent O(5) atoms to form distorted LuO7 pentagonal bipyramids that share corners with two equivalent Lu(2)O7 hexagonal pyramids, corners with three equivalent Ti(1)O5 trigonal bipyramids, edges with three equivalent Lu(2)O7 hexagonal pyramids, edges with two equivalent Lu(1)O7 pentagonal bipyramids, and edges with two equivalent Ti(1)O5 trigonal bipyramids. In the second Lu site, Lu(2) is bonded to one O(4), one O(5), two equivalent O(3), and three equivalent O(1) atoms to form distorted LuO7 hexagonal pyramids that share corners with two equivalent Lu(1)O7 pentagonal bipyramids,  a cornercorner with one Ti(1)O5 trigonal bipyramid, edges with four equivalent Lu(2)O7 hexagonal pyramids, edges with three equivalent Lu(1)O7 pentagonal bipyramids, and edges with two equivalent Ti(1)O5 trigonal bipyramids. Ti(1) is bonded to one O(2), one O(3), one O(5), and two equivalent O(4) atoms to form distorted TiO5 trigonal bipyramids that share  a cornercorner with one Lu(2)O7 hexagonal pyramid, corners with three equivalent Lu(1)O7 pentagonal bipyramids, corners with two equivalent Ti(1)O5 trigonal bipyramids, edges with two equivalent Lu(2)O7 hexagonal pyramids, and edges with two equivalent Lu(1)O7 pentagonal bipyramids. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Lu(1) and three equivalent Lu(2) atoms to form OLu4 tetrahedra that share corners with two equivalent O(4)Lu2Ti2 tetrahedra, corners with two equivalent O(1)Lu4 tetrahedra, corners with five equivalent O(3)Lu3Ti tetrahedra, corners with five equivalent O(5)Lu3Ti tetrahedra,  an edgeedge with one O(4)Lu2Ti2 tetrahedra,  an edgeedge with one O(3)Lu3Ti tetrahedra, and edges with two equivalent O(1)Lu4 tetrahedra. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Lu(1) and one Ti(1) atom. In the third O site, O(3) is bonded to one Lu(1), two equivalent Lu(2), and one Ti(1) atom to form OLu3Ti tetrahedra that share  a cornercorner with one O(4)Lu2Ti2 tetrahedra,  a cornercorner with one O(5)Lu3Ti tetrahedra, corners with two equivalent O(3)Lu3Ti tetrahedra, corners with five equivalent O(1)Lu4 tetrahedra,  an edgeedge with one O(1)Lu4 tetrahedra, edges with two equivalent O(4)Lu2Ti2 tetrahedra, and edges with two equivalent O(5)Lu3Ti tetrahedra. In the fourth O site, O(4) is bonded to one Lu(1), one Lu(2), and two equivalent Ti(1) atoms to form OLu2Ti2 tetrahedra that share  a cornercorner with one O(3)Lu3Ti tetrahedra,  a cornercorner with one O(5)Lu3Ti tetrahedra, corners with two equivalent O(4)Lu2Ti2 tetrahedra, corners with two equivalent O(1)Lu4 tetrahedra,  an edgeedge with one O(1)Lu4 tetrahedra, edges with two equivalent O(3)Lu3Ti tetrahedra, and edges with two equivalent O(5)Lu3Ti tetrahedra. In the fifth O site, O(5) is bonded to one Lu(2), two equivalent Lu(1), and one Ti(1) atom to form OLu3Ti tetrahedra that share  a cornercorner with one O(4)Lu2Ti2 tetrahedra,  a cornercorner with one O(3)Lu3Ti tetrahedra, corners with two equivalent O(5)Lu3Ti tetrahedra, corners with five equivalent O(1)Lu4 tetrahedra, edges with two equivalent O(4)Lu2Ti2 tetrahedra, and edges with two equivalent O(3)Lu3Ti tetrahedra.
Lu2TiO5 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Lu sites. In the first Lu site, Lu(1) is bonded to one O(1), one O(3), one O(4), two equivalent O(2), and two equivalent O(5) atoms to form distorted LuO7 pentagonal bipyramids that share corners with two equivalent Lu(2)O7 hexagonal pyramids, corners with three equivalent Ti(1)O5 trigonal bipyramids, edges with three equivalent Lu(2)O7 hexagonal pyramids, edges with two equivalent Lu(1)O7 pentagonal bipyramids, and edges with two equivalent Ti(1)O5 trigonal bipyramids. The Lu(1)-O(1) bond length is 2.26 Å. The Lu(1)-O(3) bond length is 2.23 Å. The Lu(1)-O(4) bond length is 2.28 Å. Both Lu(1)-O(2) bond lengths are 2.30 Å. Both Lu(1)-O(5) bond lengths are 2.21 Å. In the second Lu site, Lu(2) is bonded to one O(4), one O(5), two equivalent O(3), and three equivalent O(1) atoms to form distorted LuO7 hexagonal pyramids that share corners with two equivalent Lu(1)O7 pentagonal bipyramids,  a cornercorner with one Ti(1)O5 trigonal bipyramid, edges with four equivalent Lu(2)O7 hexagonal pyramids, edges with three equivalent Lu(1)O7 pentagonal bipyramids, and edges with two equivalent Ti(1)O5 trigonal bipyramids. The Lu(2)-O(4) bond length is 2.28 Å. The Lu(2)-O(5) bond length is 2.24 Å. Both Lu(2)-O(3) bond lengths are 2.28 Å. All Lu(2)-O(1) bond lengths are 2.29 Å. Ti(1) is bonded to one O(2), one O(3), one O(5), and two equivalent O(4) atoms to form distorted TiO5 trigonal bipyramids that share  a cornercorner with one Lu(2)O7 hexagonal pyramid, corners with three equivalent Lu(1)O7 pentagonal bipyramids, corners with two equivalent Ti(1)O5 trigonal bipyramids, edges with two equivalent Lu(2)O7 hexagonal pyramids, and edges with two equivalent Lu(1)O7 pentagonal bipyramids. The Ti(1)-O(2) bond length is 1.78 Å. The Ti(1)-O(3) bond length is 1.90 Å. The Ti(1)-O(5) bond length is 1.90 Å. Both Ti(1)-O(4) bond lengths are 1.93 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Lu(1) and three equivalent Lu(2) atoms to form OLu4 tetrahedra that share corners with two equivalent O(4)Lu2Ti2 tetrahedra, corners with two equivalent O(1)Lu4 tetrahedra, corners with five equivalent O(3)Lu3Ti tetrahedra, corners with five equivalent O(5)Lu3Ti tetrahedra,  an edgeedge with one O(4)Lu2Ti2 tetrahedra,  an edgeedge with one O(3)Lu3Ti tetrahedra, and edges with two equivalent O(1)Lu4 tetrahedra. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Lu(1) and one Ti(1) atom. In the third O site, O(3) is bonded to one Lu(1), two equivalent Lu(2), and one Ti(1) atom to form OLu3Ti tetrahedra that share  a cornercorner with one O(4)Lu2Ti2 tetrahedra,  a cornercorner with one O(5)Lu3Ti tetrahedra, corners with two equivalent O(3)Lu3Ti tetrahedra, corners with five equivalent O(1)Lu4 tetrahedra,  an edgeedge with one O(1)Lu4 tetrahedra, edges with two equivalent O(4)Lu2Ti2 tetrahedra, and edges with two equivalent O(5)Lu3Ti tetrahedra. In the fourth O site, O(4) is bonded to one Lu(1), one Lu(2), and two equivalent Ti(1) atoms to form OLu2Ti2 tetrahedra that share  a cornercorner with one O(3)Lu3Ti tetrahedra,  a cornercorner with one O(5)Lu3Ti tetrahedra, corners with two equivalent O(4)Lu2Ti2 tetrahedra, corners with two equivalent O(1)Lu4 tetrahedra,  an edgeedge with one O(1)Lu4 tetrahedra, edges with two equivalent O(3)Lu3Ti tetrahedra, and edges with two equivalent O(5)Lu3Ti tetrahedra. In the fifth O site, O(5) is bonded to one Lu(2), two equivalent Lu(1), and one Ti(1) atom to form OLu3Ti tetrahedra that share  a cornercorner with one O(4)Lu2Ti2 tetrahedra,  a cornercorner with one O(3)Lu3Ti tetrahedra, corners with two equivalent O(5)Lu3Ti tetrahedra, corners with five equivalent O(1)Lu4 tetrahedra, edges with two equivalent O(4)Lu2Ti2 tetrahedra, and edges with two equivalent O(3)Lu3Ti tetrahedra.