Nd2Ti4O11 crystallizes in the monoclinic C2/c space group. Nd(1) is bonded in a 8-coordinate geometry to one O(3), one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(5), one O(6), and two equivalent O(4) atoms. In the second Ti site, Ti(2) is bonded to one O(2), one O(4), one O(5), one O(6), and two equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 59°. There are six inequivalent O sites. In the first O site, O(6) is bonded to two equivalent Ti(1) and two equivalent Ti(2) atoms to form distorted corner-sharing OTi4 trigonal pyramids. In the second O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Nd(1) and one Ti(1) atom. In the third O site, O(2) is bonded to two equivalent Nd(1), one Ti(1), and one Ti(2) atom to form distorted ONd2Ti2 tetrahedra that share corners with two equivalent O(6)Ti4 trigonal pyramids and  an edgeedge with one O(2)Nd2Ti2 tetrahedra. In the fourth O site, O(3) is bonded in a 3-coordinate geometry to one Nd(1) and two equivalent Ti(2) atoms. In the fifth O site, O(4) is bonded in a 4-coordinate geometry to one Nd(1), one Ti(2), and two equivalent Ti(1) atoms. In the sixth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Nd(1), one Ti(1), and one Ti(2) atom.
Nd2Ti4O11 crystallizes in the monoclinic C2/c space group. Nd(1) is bonded in a 8-coordinate geometry to one O(3), one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms. The Nd(1)-O(3) bond length is 2.43 Å. The Nd(1)-O(4) bond length is 2.65 Å. Both Nd(1)-O(1) bond lengths are 2.40 Å. There is one shorter (2.37 Å) and one longer (2.58 Å) Nd(1)-O(2) bond length. There is one shorter (2.38 Å) and one longer (2.65 Å) Nd(1)-O(5) bond length. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(5), one O(6), and two equivalent O(4) atoms. The Ti(1)-O(1) bond length is 1.76 Å. The Ti(1)-O(2) bond length is 1.87 Å. The Ti(1)-O(5) bond length is 1.93 Å. The Ti(1)-O(6) bond length is 2.06 Å. There is one shorter (2.00 Å) and one longer (2.43 Å) Ti(1)-O(4) bond length. In the second Ti site, Ti(2) is bonded to one O(2), one O(4), one O(5), one O(6), and two equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 59°. The Ti(2)-O(2) bond length is 2.06 Å. The Ti(2)-O(4) bond length is 1.93 Å. The Ti(2)-O(5) bond length is 1.97 Å. The Ti(2)-O(6) bond length is 2.13 Å. There is one shorter (1.89 Å) and one longer (1.92 Å) Ti(2)-O(3) bond length. There are six inequivalent O sites. In the first O site, O(6) is bonded to two equivalent Ti(1) and two equivalent Ti(2) atoms to form distorted corner-sharing OTi4 trigonal pyramids. In the second O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Nd(1) and one Ti(1) atom. In the third O site, O(2) is bonded to two equivalent Nd(1), one Ti(1), and one Ti(2) atom to form distorted ONd2Ti2 tetrahedra that share corners with two equivalent O(6)Ti4 trigonal pyramids and  an edgeedge with one O(2)Nd2Ti2 tetrahedra. In the fourth O site, O(3) is bonded in a 3-coordinate geometry to one Nd(1) and two equivalent Ti(2) atoms. In the fifth O site, O(4) is bonded in a 4-coordinate geometry to one Nd(1), one Ti(2), and two equivalent Ti(1) atoms. In the sixth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Nd(1), one Ti(1), and one Ti(2) atom.