NaTi3AlO8 crystallizes in the monoclinic Cm space group. Na(1) is bonded in a 4-coordinate geometry to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(2), one O(3), one O(5), and two equivalent O(8) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Al(1)O6 octahedra, corners with two equivalent Ti(1)O6 octahedra,  an edgeedge with one Ti(2)O6 octahedra,  an edgeedge with one Al(1)O6 octahedra, and edges with two equivalent Ti(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 17-28°. In the second Ti site, Ti(2) is bonded to one O(1), one O(2), one O(4), one O(6), and two equivalent O(7) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Al(1)O6 octahedra, corners with two equivalent Ti(2)O6 octahedra,  an edgeedge with one Ti(1)O6 octahedra,  an edgeedge with one Ti(3)O6 octahedra, and edges with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 19-28°. In the third Ti site, Ti(3) is bonded to one O(2), one O(4), one O(6), one O(8), and two equivalent O(5) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra, corners with two equivalent Ti(3)O6 octahedra,  an edgeedge with one Ti(2)O6 octahedra, edges with two equivalent Ti(1)O6 octahedra, and edges with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 19-28°. Al(1) is bonded to one O(1), one O(3), one O(5), one O(7), and two equivalent O(6) atoms to form AlO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra, corners with two equivalent Al(1)O6 octahedra,  an edgeedge with one Ti(1)O6 octahedra, edges with two equivalent Ti(2)O6 octahedra, and edges with two equivalent Ti(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 17-22°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Na(1), one Ti(1), one Ti(2), and one Al(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ti(1), one Ti(2), and one Ti(3) atom. In the third O site, O(3) is bonded in a distorted see-saw-like geometry to two equivalent Na(1), one Ti(1), and one Al(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(1), one Ti(2), and one Ti(3) atom. In the fifth O site, O(5) is bonded to one Ti(1), two equivalent Ti(3), and one Al(1) atom to form distorted corner-sharing OTi3Al trigonal pyramids. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ti(2), one Ti(3), and two equivalent Al(1) atoms. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to two equivalent Ti(2) and one Al(1) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Ti(3) and two equivalent Ti(1) atoms.
NaTi3AlO8 crystallizes in the monoclinic Cm space group. Na(1) is bonded in a 4-coordinate geometry to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. Both Na(1)-O(1) bond lengths are 2.82 Å. Both Na(1)-O(3) bond lengths are 2.44 Å. Both Na(1)-O(4) bond lengths are 2.49 Å. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(2), one O(3), one O(5), and two equivalent O(8) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Al(1)O6 octahedra, corners with two equivalent Ti(1)O6 octahedra,  an edgeedge with one Ti(2)O6 octahedra,  an edgeedge with one Al(1)O6 octahedra, and edges with two equivalent Ti(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 17-28°. The Ti(1)-O(1) bond length is 2.26 Å. The Ti(1)-O(2) bond length is 1.88 Å. The Ti(1)-O(3) bond length is 1.80 Å. The Ti(1)-O(5) bond length is 2.16 Å. Both Ti(1)-O(8) bond lengths are 1.95 Å. In the second Ti site, Ti(2) is bonded to one O(1), one O(2), one O(4), one O(6), and two equivalent O(7) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Al(1)O6 octahedra, corners with two equivalent Ti(2)O6 octahedra,  an edgeedge with one Ti(1)O6 octahedra,  an edgeedge with one Ti(3)O6 octahedra, and edges with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 19-28°. The Ti(2)-O(1) bond length is 1.85 Å. The Ti(2)-O(2) bond length is 2.09 Å. The Ti(2)-O(4) bond length is 1.94 Å. The Ti(2)-O(6) bond length is 2.17 Å. Both Ti(2)-O(7) bond lengths are 1.96 Å. In the third Ti site, Ti(3) is bonded to one O(2), one O(4), one O(6), one O(8), and two equivalent O(5) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra, corners with two equivalent Ti(3)O6 octahedra,  an edgeedge with one Ti(2)O6 octahedra, edges with two equivalent Ti(1)O6 octahedra, and edges with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 19-28°. The Ti(3)-O(2) bond length is 1.96 Å. The Ti(3)-O(4) bond length is 1.81 Å. The Ti(3)-O(6) bond length is 2.18 Å. The Ti(3)-O(8) bond length is 1.98 Å. Both Ti(3)-O(5) bond lengths are 1.95 Å. Al(1) is bonded to one O(1), one O(3), one O(5), one O(7), and two equivalent O(6) atoms to form AlO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra, corners with two equivalent Al(1)O6 octahedra,  an edgeedge with one Ti(1)O6 octahedra, edges with two equivalent Ti(2)O6 octahedra, and edges with two equivalent Ti(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 17-22°. The Al(1)-O(1) bond length is 1.92 Å. The Al(1)-O(3) bond length is 1.86 Å. The Al(1)-O(5) bond length is 2.08 Å. The Al(1)-O(7) bond length is 1.94 Å. Both Al(1)-O(6) bond lengths are 1.93 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Na(1), one Ti(1), one Ti(2), and one Al(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ti(1), one Ti(2), and one Ti(3) atom. In the third O site, O(3) is bonded in a distorted see-saw-like geometry to two equivalent Na(1), one Ti(1), and one Al(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(1), one Ti(2), and one Ti(3) atom. In the fifth O site, O(5) is bonded to one Ti(1), two equivalent Ti(3), and one Al(1) atom to form distorted corner-sharing OTi3Al trigonal pyramids. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ti(2), one Ti(3), and two equivalent Al(1) atoms. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to two equivalent Ti(2) and one Al(1) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Ti(3) and two equivalent Ti(1) atoms.