MgPr2Ti4O12 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(10), one O(5), one O(6), and one O(8) atom to form distorted MgO5 trigonal bipyramids that share  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Ti(1)O5 trigonal bipyramid,  a cornercorner with one Ti(4)O5 trigonal bipyramid,  an edgeedge with one Ti(1)O5 trigonal bipyramid, and  an edgeedge with one Ti(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 44°. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 6-coordinate geometry to one O(12), one O(2), one O(4), one O(5), one O(7), and one O(9) atom. In the second Pr site, Pr(2) is bonded in a 6-coordinate geometry to one O(1), one O(11), one O(3), one O(4), one O(6), and one O(8) atom. There are four inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(10), one O(12), one O(2), and one O(5) atom to form TiO5 trigonal bipyramids that share  a cornercorner with one Ti(2)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, corners with three equivalent Ti(4)O5 trigonal bipyramids, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. In the second Ti site, Ti(2) is bonded to one O(11), one O(12), one O(3), and one O(9) atom to form TiO4 tetrahedra that share corners with three equivalent Ti(3)O6 octahedra and  a cornercorner with one Ti(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 21-43°. In the third Ti site, Ti(3) is bonded to one O(11), one O(3), one O(4), one O(6), one O(7), and one O(9) atom to form distorted TiO6 octahedra that share corners with three equivalent Ti(2)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, and  a cornercorner with one Ti(4)O5 trigonal bipyramid. In the fourth Ti site, Ti(4) is bonded to one O(10), one O(2), one O(5), one O(7), and one O(8) atom to form distorted TiO5 trigonal bipyramids that share  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, corners with three equivalent Ti(1)O5 trigonal bipyramids, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 31°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a T-shaped geometry to one Mg(1), one Pr(2), and one Ti(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Pr(1), one Ti(1), and one Ti(4) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Pr(2), one Ti(2), and one Ti(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Pr(1), one Pr(2), and one Ti(3) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Pr(1), one Ti(1), and one Ti(4) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Pr(2), and one Ti(3) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Pr(1), one Ti(3), and one Ti(4) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Mg(1), one Pr(2), and one Ti(4) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Pr(1), one Ti(2), and one Ti(3) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Mg(1), one Ti(1), and one Ti(4) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Pr(2), one Ti(2), and one Ti(3) atom. In the twelfth O site, O(12) is bonded in a distorted T-shaped geometry to one Pr(1), one Ti(1), and one Ti(2) atom.
MgPr2Ti4O12 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(10), one O(5), one O(6), and one O(8) atom to form distorted MgO5 trigonal bipyramids that share  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Ti(1)O5 trigonal bipyramid,  a cornercorner with one Ti(4)O5 trigonal bipyramid,  an edgeedge with one Ti(1)O5 trigonal bipyramid, and  an edgeedge with one Ti(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 44°. The Mg(1)-O(1) bond length is 2.22 Å. The Mg(1)-O(10) bond length is 1.99 Å. The Mg(1)-O(5) bond length is 2.10 Å. The Mg(1)-O(6) bond length is 1.99 Å. The Mg(1)-O(8) bond length is 2.05 Å. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 6-coordinate geometry to one O(12), one O(2), one O(4), one O(5), one O(7), and one O(9) atom. The Pr(1)-O(12) bond length is 2.34 Å. The Pr(1)-O(2) bond length is 2.33 Å. The Pr(1)-O(4) bond length is 2.40 Å. The Pr(1)-O(5) bond length is 2.58 Å. The Pr(1)-O(7) bond length is 2.43 Å. The Pr(1)-O(9) bond length is 2.48 Å. In the second Pr site, Pr(2) is bonded in a 6-coordinate geometry to one O(1), one O(11), one O(3), one O(4), one O(6), and one O(8) atom. The Pr(2)-O(1) bond length is 2.32 Å. The Pr(2)-O(11) bond length is 2.48 Å. The Pr(2)-O(3) bond length is 2.41 Å. The Pr(2)-O(4) bond length is 2.42 Å. The Pr(2)-O(6) bond length is 2.50 Å. The Pr(2)-O(8) bond length is 2.53 Å. There are four inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(10), one O(12), one O(2), and one O(5) atom to form TiO5 trigonal bipyramids that share  a cornercorner with one Ti(2)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, corners with three equivalent Ti(4)O5 trigonal bipyramids, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. The Ti(1)-O(1) bond length is 1.80 Å. The Ti(1)-O(10) bond length is 1.87 Å. The Ti(1)-O(12) bond length is 2.15 Å. The Ti(1)-O(2) bond length is 1.94 Å. The Ti(1)-O(5) bond length is 1.92 Å. In the second Ti site, Ti(2) is bonded to one O(11), one O(12), one O(3), and one O(9) atom to form TiO4 tetrahedra that share corners with three equivalent Ti(3)O6 octahedra and  a cornercorner with one Ti(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 21-43°. The Ti(2)-O(11) bond length is 1.82 Å. The Ti(2)-O(12) bond length is 1.79 Å. The Ti(2)-O(3) bond length is 1.85 Å. The Ti(2)-O(9) bond length is 1.82 Å. In the third Ti site, Ti(3) is bonded to one O(11), one O(3), one O(4), one O(6), one O(7), and one O(9) atom to form distorted TiO6 octahedra that share corners with three equivalent Ti(2)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, and  a cornercorner with one Ti(4)O5 trigonal bipyramid. The Ti(3)-O(11) bond length is 2.16 Å. The Ti(3)-O(3) bond length is 1.96 Å. The Ti(3)-O(4) bond length is 1.85 Å. The Ti(3)-O(6) bond length is 1.81 Å. The Ti(3)-O(7) bond length is 2.41 Å. The Ti(3)-O(9) bond length is 2.08 Å. In the fourth Ti site, Ti(4) is bonded to one O(10), one O(2), one O(5), one O(7), and one O(8) atom to form distorted TiO5 trigonal bipyramids that share  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, corners with three equivalent Ti(1)O5 trigonal bipyramids, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 31°. The Ti(4)-O(10) bond length is 2.00 Å. The Ti(4)-O(2) bond length is 1.99 Å. The Ti(4)-O(5) bond length is 2.19 Å. The Ti(4)-O(7) bond length is 1.80 Å. The Ti(4)-O(8) bond length is 1.82 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a T-shaped geometry to one Mg(1), one Pr(2), and one Ti(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Pr(1), one Ti(1), and one Ti(4) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Pr(2), one Ti(2), and one Ti(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Pr(1), one Pr(2), and one Ti(3) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Pr(1), one Ti(1), and one Ti(4) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Pr(2), and one Ti(3) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Pr(1), one Ti(3), and one Ti(4) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Mg(1), one Pr(2), and one Ti(4) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Pr(1), one Ti(2), and one Ti(3) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Mg(1), one Ti(1), and one Ti(4) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Pr(2), one Ti(2), and one Ti(3) atom. In the twelfth O site, O(12) is bonded in a distorted T-shaped geometry to one Pr(1), one Ti(1), and one Ti(2) atom.