MgTiNbO4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with four equivalent Mg(1)O6 octahedra, edges with four equivalent Ti(1)O6 octahedra, and edges with four equivalent Nb(1)O6 octahedra. The corner-sharing octahedra are not tilted. Ti(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form TiO6 octahedra that share corners with four equivalent Ti(1)O6 octahedra, edges with four equivalent Mg(1)O6 octahedra, and edges with four equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles are 4°. Nb(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form NbO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, edges with four equivalent Mg(1)O6 octahedra, and edges with four equivalent Ti(1)O6 octahedra. The corner-sharing octahedra are not tilted. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Ti(1), and two equivalent Nb(1) atoms to form a mixture of edge and corner-sharing OMg2TiNb2 square pyramids. In the second O site, O(2) is bonded in a square co-planar geometry to one Mg(1), two equivalent Ti(1), and one Nb(1) atom. In the third O site, O(3) is bonded to two equivalent Mg(1), one Ti(1), and two equivalent Nb(1) atoms to form a mixture of edge and corner-sharing OMg2TiNb2 square pyramids. In the fourth O site, O(4) is bonded in a square co-planar geometry to one Mg(1), two equivalent Ti(1), and one Nb(1) atom.
MgTiNbO4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with four equivalent Mg(1)O6 octahedra, edges with four equivalent Ti(1)O6 octahedra, and edges with four equivalent Nb(1)O6 octahedra. The corner-sharing octahedra are not tilted. The Mg(1)-O(2) bond length is 2.04 Å. The Mg(1)-O(4) bond length is 2.04 Å. Both Mg(1)-O(1) bond lengths are 2.10 Å. Both Mg(1)-O(3) bond lengths are 2.10 Å. Ti(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form TiO6 octahedra that share corners with four equivalent Ti(1)O6 octahedra, edges with four equivalent Mg(1)O6 octahedra, and edges with four equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles are 4°. The Ti(1)-O(1) bond length is 2.11 Å. The Ti(1)-O(3) bond length is 2.12 Å. There is one shorter (2.10 Å) and one longer (2.11 Å) Ti(1)-O(2) bond length. Both Ti(1)-O(4) bond lengths are 2.10 Å. Nb(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form NbO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, edges with four equivalent Mg(1)O6 octahedra, and edges with four equivalent Ti(1)O6 octahedra. The corner-sharing octahedra are not tilted. The Nb(1)-O(2) bond length is 2.18 Å. The Nb(1)-O(4) bond length is 2.18 Å. Both Nb(1)-O(1) bond lengths are 2.10 Å. Both Nb(1)-O(3) bond lengths are 2.10 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Ti(1), and two equivalent Nb(1) atoms to form a mixture of edge and corner-sharing OMg2TiNb2 square pyramids. In the second O site, O(2) is bonded in a square co-planar geometry to one Mg(1), two equivalent Ti(1), and one Nb(1) atom. In the third O site, O(3) is bonded to two equivalent Mg(1), one Ti(1), and two equivalent Nb(1) atoms to form a mixture of edge and corner-sharing OMg2TiNb2 square pyramids. In the fourth O site, O(4) is bonded in a square co-planar geometry to one Mg(1), two equivalent Ti(1), and one Nb(1) atom.