Ba2YFe2TlO7 crystallizes in the tetragonal P4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(1), and four equivalent O(2) atoms. Y(1) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. Fe(1) is bonded to one O(1) and four equivalent O(2) atoms to form distorted corner-sharing FeO5 square pyramids. Tl(1) is bonded in a distorted linear geometry to two equivalent O(1) and four equivalent O(3) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(1), one Fe(1), and one Tl(1) atom to form distorted OBa4TlFe octahedra that share corners with five equivalent O(1)Ba4TlFe octahedra, edges with four equivalent O(3)Ba2Tl4 octahedra, and edges with four equivalent O(1)Ba4TlFe octahedra. The corner-sharing octahedral tilt angles range from 0-18°. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Y(1), and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded to two equivalent Ba(1) and four equivalent Tl(1) atoms to form distorted OBa2Tl4 octahedra that share corners with four equivalent O(3)Ba2Tl4 octahedra, edges with four equivalent O(3)Ba2Tl4 octahedra, and edges with eight equivalent O(1)Ba4TlFe octahedra. The corner-sharing octahedra are not tilted.
Ba2YFe2TlO7 crystallizes in the tetragonal P4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(1), and four equivalent O(2) atoms. The Ba(1)-O(3) bond length is 2.60 Å. All Ba(1)-O(1) bond lengths are 2.84 Å. All Ba(1)-O(2) bond lengths are 3.15 Å. Y(1) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. All Y(1)-O(2) bond lengths are 2.45 Å. Fe(1) is bonded to one O(1) and four equivalent O(2) atoms to form distorted corner-sharing FeO5 square pyramids. The Fe(1)-O(1) bond length is 2.66 Å. All Fe(1)-O(2) bond lengths are 2.00 Å. Tl(1) is bonded in a distorted linear geometry to two equivalent O(1) and four equivalent O(3) atoms. Both Tl(1)-O(1) bond lengths are 2.16 Å. All Tl(1)-O(3) bond lengths are 2.80 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(1), one Fe(1), and one Tl(1) atom to form distorted OBa4TlFe octahedra that share corners with five equivalent O(1)Ba4TlFe octahedra, edges with four equivalent O(3)Ba2Tl4 octahedra, and edges with four equivalent O(1)Ba4TlFe octahedra. The corner-sharing octahedral tilt angles range from 0-18°. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Y(1), and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded to two equivalent Ba(1) and four equivalent Tl(1) atoms to form distorted OBa2Tl4 octahedra that share corners with four equivalent O(3)Ba2Tl4 octahedra, edges with four equivalent O(3)Ba2Tl4 octahedra, and edges with eight equivalent O(1)Ba4TlFe octahedra. The corner-sharing octahedra are not tilted.