MgTi2(NiO3)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted TiO6 octahedra that share corners with three equivalent Ni(1)O6 octahedra, edges with three equivalent Ti(2)O6 octahedra, and  a faceface with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-47°. In the second Ti site, Ti(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form TiO6 octahedra that share corners with three equivalent Ni(1)O6 octahedra, edges with three equivalent Ti(1)O6 octahedra, and  a faceface with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-35°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form NiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra, corners with three equivalent Ti(2)O6 octahedra,  a faceface with one Ti(1)O6 octahedra, and  a faceface with one Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-47°. In the second Ni site, Ni(2) is bonded in a trigonal planar geometry to one O(2), one O(3), and one O(6) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Ti(1), one Ti(2), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OMgTi2Ni trigonal pyramids. In the second O site, O(2) is bonded to one Mg(1), one Ti(1), one Ti(2), one Ni(1), and one Ni(2) atom to form distorted OMgTi2Ni2 trigonal bipyramids that share  a cornercorner with one O(3)MgTi2Ni2 trigonal bipyramid, corners with two equivalent O(1)MgTi2Ni trigonal pyramids, edges with two equivalent O(3)MgTi2Ni2 trigonal bipyramids, and  an edgeedge with one O(1)MgTi2Ni trigonal pyramid. In the third O site, O(3) is bonded to one Mg(1), one Ti(1), one Ti(2), one Ni(1), and one Ni(2) atom to form distorted OMgTi2Ni2 trigonal bipyramids that share  a cornercorner with one O(2)MgTi2Ni2 trigonal bipyramid, corners with four equivalent O(1)MgTi2Ni trigonal pyramids, and edges with two equivalent O(2)MgTi2Ni2 trigonal bipyramids. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Ti(1), one Ti(2), and one Ni(1) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Ti(1), one Ti(2), and one Ni(1) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Mg(1), one Ti(1), one Ti(2), one Ni(1), and one Ni(2) atom.
MgTi2(NiO3)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. The Mg(1)-O(1) bond length is 2.06 Å. The Mg(1)-O(2) bond length is 2.40 Å. The Mg(1)-O(3) bond length is 2.26 Å. The Mg(1)-O(4) bond length is 2.08 Å. The Mg(1)-O(5) bond length is 2.04 Å. The Mg(1)-O(6) bond length is 2.31 Å. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted TiO6 octahedra that share corners with three equivalent Ni(1)O6 octahedra, edges with three equivalent Ti(2)O6 octahedra, and  a faceface with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-47°. The Ti(1)-O(1) bond length is 2.01 Å. The Ti(1)-O(2) bond length is 2.08 Å. The Ti(1)-O(3) bond length is 2.14 Å. The Ti(1)-O(4) bond length is 1.90 Å. The Ti(1)-O(5) bond length is 1.97 Å. The Ti(1)-O(6) bond length is 2.36 Å. In the second Ti site, Ti(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form TiO6 octahedra that share corners with three equivalent Ni(1)O6 octahedra, edges with three equivalent Ti(1)O6 octahedra, and  a faceface with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-35°. The Ti(2)-O(1) bond length is 2.03 Å. The Ti(2)-O(2) bond length is 2.04 Å. The Ti(2)-O(3) bond length is 1.96 Å. The Ti(2)-O(4) bond length is 2.17 Å. The Ti(2)-O(5) bond length is 2.04 Å. The Ti(2)-O(6) bond length is 1.92 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form NiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra, corners with three equivalent Ti(2)O6 octahedra,  a faceface with one Ti(1)O6 octahedra, and  a faceface with one Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-47°. The Ni(1)-O(1) bond length is 2.10 Å. The Ni(1)-O(2) bond length is 2.04 Å. The Ni(1)-O(3) bond length is 2.05 Å. The Ni(1)-O(4) bond length is 2.12 Å. The Ni(1)-O(5) bond length is 2.10 Å. The Ni(1)-O(6) bond length is 2.03 Å. In the second Ni site, Ni(2) is bonded in a trigonal planar geometry to one O(2), one O(3), and one O(6) atom. The Ni(2)-O(2) bond length is 1.98 Å. The Ni(2)-O(3) bond length is 2.02 Å. The Ni(2)-O(6) bond length is 2.02 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Ti(1), one Ti(2), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OMgTi2Ni trigonal pyramids. In the second O site, O(2) is bonded to one Mg(1), one Ti(1), one Ti(2), one Ni(1), and one Ni(2) atom to form distorted OMgTi2Ni2 trigonal bipyramids that share  a cornercorner with one O(3)MgTi2Ni2 trigonal bipyramid, corners with two equivalent O(1)MgTi2Ni trigonal pyramids, edges with two equivalent O(3)MgTi2Ni2 trigonal bipyramids, and  an edgeedge with one O(1)MgTi2Ni trigonal pyramid. In the third O site, O(3) is bonded to one Mg(1), one Ti(1), one Ti(2), one Ni(1), and one Ni(2) atom to form distorted OMgTi2Ni2 trigonal bipyramids that share  a cornercorner with one O(2)MgTi2Ni2 trigonal bipyramid, corners with four equivalent O(1)MgTi2Ni trigonal pyramids, and edges with two equivalent O(2)MgTi2Ni2 trigonal bipyramids. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Ti(1), one Ti(2), and one Ni(1) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Ti(1), one Ti(2), and one Ni(1) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Mg(1), one Ti(1), one Ti(2), one Ni(1), and one Ni(2) atom.