Ba2Mg3Tl2(FeO3)4 crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(1), and four equivalent O(4) atoms. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. In the second Mg site, Mg(2) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a rectangular see-saw-like geometry to four equivalent O(2) atoms. In the second Fe site, Fe(2) is bonded in a rectangular see-saw-like geometry to four equivalent O(1) atoms. Tl(1) is bonded to one O(4) and five equivalent O(3) atoms to form a mixture of distorted edge and corner-sharing TlO6 octahedra. The corner-sharing octahedral tilt angles are 5°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted see-saw-like geometry to two equivalent Ba(1), two equivalent Mg(1), and two equivalent Fe(2) atoms. In the second O site, O(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), and two equivalent Fe(1) atoms to form a mixture of distorted edge, face, and corner-sharing OMg4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the third O site, O(3) is bonded to one Ba(1) and five equivalent Tl(1) atoms to form a mixture of distorted edge and corner-sharing OBaTl5 octahedra. The corner-sharing octahedral tilt angles are 5°. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to four equivalent Ba(1) and one Tl(1) atom.
Ba2Mg3Tl2(FeO3)4 crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(1), and four equivalent O(4) atoms. The Ba(1)-O(3) bond length is 2.87 Å. All Ba(1)-O(1) bond lengths are 3.04 Å. All Ba(1)-O(4) bond lengths are 2.81 Å. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. All Mg(1)-O(1) bond lengths are 2.27 Å. All Mg(1)-O(2) bond lengths are 2.61 Å. In the second Mg site, Mg(2) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. All Mg(2)-O(2) bond lengths are 2.42 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a rectangular see-saw-like geometry to four equivalent O(2) atoms. All Fe(1)-O(2) bond lengths are 1.95 Å. In the second Fe site, Fe(2) is bonded in a rectangular see-saw-like geometry to four equivalent O(1) atoms. All Fe(2)-O(1) bond lengths are 1.95 Å. Tl(1) is bonded to one O(4) and five equivalent O(3) atoms to form a mixture of distorted edge and corner-sharing TlO6 octahedra. The corner-sharing octahedral tilt angles are 5°. The Tl(1)-O(4) bond length is 2.18 Å. There is one shorter (2.20 Å) and four longer (2.75 Å) Tl(1)-O(3) bond lengths. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted see-saw-like geometry to two equivalent Ba(1), two equivalent Mg(1), and two equivalent Fe(2) atoms. In the second O site, O(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), and two equivalent Fe(1) atoms to form a mixture of distorted edge, face, and corner-sharing OMg4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the third O site, O(3) is bonded to one Ba(1) and five equivalent Tl(1) atoms to form a mixture of distorted edge and corner-sharing OBaTl5 octahedra. The corner-sharing octahedral tilt angles are 5°. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to four equivalent Ba(1) and one Tl(1) atom.