MgTi4Pb2O9F2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(3) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(2), one O(3), one O(5), two equivalent O(1), and one F(1) atom to form distorted TiO5F octahedra that share  a cornercorner with one Ti(2)O6 octahedra, corners with three equivalent Ti(1)O5F octahedra, and edges with two equivalent Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-17°. In the second Ti site, Ti(2) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(4) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(1)O5F octahedra, corners with two equivalent Ti(2)O6 octahedra,  an edgeedge with one Ti(2)O6 octahedra, and edges with two equivalent Ti(1)O5F octahedra. The corner-sharing octahedral tilt angles range from 1-17°. Pb(1) is bonded in a 3-coordinate geometry to two equivalent O(4) and one F(1) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Ti(2), and two equivalent Ti(1) atoms. In the second O site, O(2) is bonded in a T-shaped geometry to one Ti(1) and two equivalent Ti(2) atoms. In the third O site, O(3) is bonded in a square co-planar geometry to two equivalent Mg(1) and two equivalent Ti(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Ti(2) and two equivalent Pb(1) atoms to form a mixture of distorted edge and corner-sharing OTi2Pb2 trigonal pyramids. In the fifth O site, O(5) is bonded in a linear geometry to one Ti(1) and one Ti(2) atom. F(1) is bonded in a bent 120 degrees geometry to one Ti(1) and one Pb(1) atom.
MgTi4Pb2O9F2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(3) atoms. Both Mg(1)-O(1) bond lengths are 2.01 Å. Both Mg(1)-O(3) bond lengths are 2.01 Å. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(2), one O(3), one O(5), two equivalent O(1), and one F(1) atom to form distorted TiO5F octahedra that share  a cornercorner with one Ti(2)O6 octahedra, corners with three equivalent Ti(1)O5F octahedra, and edges with two equivalent Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-17°. The Ti(1)-O(2) bond length is 2.02 Å. The Ti(1)-O(3) bond length is 2.09 Å. The Ti(1)-O(5) bond length is 1.79 Å. Both Ti(1)-O(1) bond lengths are 2.03 Å. The Ti(1)-F(1) bond length is 2.31 Å. In the second Ti site, Ti(2) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(4) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(1)O5F octahedra, corners with two equivalent Ti(2)O6 octahedra,  an edgeedge with one Ti(2)O6 octahedra, and edges with two equivalent Ti(1)O5F octahedra. The corner-sharing octahedral tilt angles range from 1-17°. The Ti(2)-O(1) bond length is 2.04 Å. The Ti(2)-O(5) bond length is 1.98 Å. Both Ti(2)-O(2) bond lengths are 2.01 Å. There is one shorter (1.97 Å) and one longer (2.13 Å) Ti(2)-O(4) bond length. Pb(1) is bonded in a 3-coordinate geometry to two equivalent O(4) and one F(1) atom. Both Pb(1)-O(4) bond lengths are 2.38 Å. The Pb(1)-F(1) bond length is 2.30 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Ti(2), and two equivalent Ti(1) atoms. In the second O site, O(2) is bonded in a T-shaped geometry to one Ti(1) and two equivalent Ti(2) atoms. In the third O site, O(3) is bonded in a square co-planar geometry to two equivalent Mg(1) and two equivalent Ti(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Ti(2) and two equivalent Pb(1) atoms to form a mixture of distorted edge and corner-sharing OTi2Pb2 trigonal pyramids. In the fifth O site, O(5) is bonded in a linear geometry to one Ti(1) and one Ti(2) atom. F(1) is bonded in a bent 120 degrees geometry to one Ti(1) and one Pb(1) atom.