Os8Tl8O27 crystallizes in the tetragonal P-4m2 space group. There are two inequivalent Os sites. In the first Os site, Os(1) is bonded to one O(1), one O(7), two equivalent O(3), and two equivalent O(9) atoms to form OsO6 octahedra that share corners with two equivalent Os(2)O6 octahedra, corners with four equivalent Os(1)O6 octahedra, and edges with four equivalent Tl(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 31-46°. In the second Os site, Os(2) is bonded to one O(4), one O(5), two equivalent O(3), and two equivalent O(6) atoms to form OsO6 octahedra that share corners with two equivalent Os(1)O6 octahedra, corners with four equivalent Os(2)O6 octahedra, and edges with two equivalent Tl(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 35-46°. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded to one O(2), one O(4), one O(7), one O(8), two equivalent O(3), and two equivalent O(9) atoms to form distorted TlO8 hexagonal bipyramids that share edges with four equivalent Tl(1)O8 hexagonal bipyramids, edges with two equivalent Os(2)O6 octahedra, and edges with four equivalent Os(1)O6 octahedra. In the second Tl site, Tl(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(5), two equivalent O(3), and two equivalent O(6) atoms. There are nine inequivalent O sites. In the first O site, O(7) is bonded in a 4-coordinate geometry to two equivalent Os(1) and two equivalent Tl(1) atoms. In the second O site, O(8) is bonded to four equivalent Tl(1) atoms to form OTl4 tetrahedra that share corners with four equivalent O(2)Tl4 tetrahedra and edges with two equivalent O(4)Tl2Os2 tetrahedra. In the third O site, O(9) is bonded in a 4-coordinate geometry to two equivalent Os(1) and two equivalent Tl(1) atoms. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent Os(1) and two equivalent Tl(2) atoms. In the fifth O site, O(2) is bonded to two equivalent Tl(1) and two equivalent Tl(2) atoms to form OTl4 tetrahedra that share corners with two equivalent O(4)Tl2Os2 tetrahedra and corners with two equivalent O(8)Tl4 tetrahedra. In the sixth O site, O(3) is bonded in a 4-coordinate geometry to one Os(1), one Os(2), one Tl(1), and one Tl(2) atom. In the seventh O site, O(4) is bonded to two equivalent Os(2) and two equivalent Tl(1) atoms to form a mixture of distorted corner and edge-sharing OTl2Os2 tetrahedra. In the eighth O site, O(5) is bonded in a distorted bent 150 degrees geometry to two equivalent Os(2) and two equivalent Tl(2) atoms. In the ninth O site, O(6) is bonded in a 4-coordinate geometry to two equivalent Os(2) and two equivalent Tl(2) atoms.
Os8Tl8O27 crystallizes in the tetragonal P-4m2 space group. There are two inequivalent Os sites. In the first Os site, Os(1) is bonded to one O(1), one O(7), two equivalent O(3), and two equivalent O(9) atoms to form OsO6 octahedra that share corners with two equivalent Os(2)O6 octahedra, corners with four equivalent Os(1)O6 octahedra, and edges with four equivalent Tl(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 31-46°. The Os(1)-O(1) bond length is 1.91 Å. The Os(1)-O(7) bond length is 1.99 Å. Both Os(1)-O(3) bond lengths are 1.97 Å. Both Os(1)-O(9) bond lengths are 1.99 Å. In the second Os site, Os(2) is bonded to one O(4), one O(5), two equivalent O(3), and two equivalent O(6) atoms to form OsO6 octahedra that share corners with two equivalent Os(1)O6 octahedra, corners with four equivalent Os(2)O6 octahedra, and edges with two equivalent Tl(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 35-46°. The Os(2)-O(4) bond length is 2.00 Å. The Os(2)-O(5) bond length is 1.93 Å. Both Os(2)-O(3) bond lengths are 1.97 Å. Both Os(2)-O(6) bond lengths are 1.95 Å. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded to one O(2), one O(4), one O(7), one O(8), two equivalent O(3), and two equivalent O(9) atoms to form distorted TlO8 hexagonal bipyramids that share edges with four equivalent Tl(1)O8 hexagonal bipyramids, edges with two equivalent Os(2)O6 octahedra, and edges with four equivalent Os(1)O6 octahedra. The Tl(1)-O(2) bond length is 2.23 Å. The Tl(1)-O(4) bond length is 2.58 Å. The Tl(1)-O(7) bond length is 2.62 Å. The Tl(1)-O(8) bond length is 2.28 Å. Both Tl(1)-O(3) bond lengths are 2.61 Å. Both Tl(1)-O(9) bond lengths are 2.62 Å. In the second Tl site, Tl(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(5), two equivalent O(3), and two equivalent O(6) atoms. The Tl(2)-O(1) bond length is 2.79 Å. The Tl(2)-O(2) bond length is 2.39 Å. The Tl(2)-O(5) bond length is 2.75 Å. Both Tl(2)-O(3) bond lengths are 2.73 Å. Both Tl(2)-O(6) bond lengths are 2.70 Å. There are nine inequivalent O sites. In the first O site, O(7) is bonded in a 4-coordinate geometry to two equivalent Os(1) and two equivalent Tl(1) atoms. In the second O site, O(8) is bonded to four equivalent Tl(1) atoms to form OTl4 tetrahedra that share corners with four equivalent O(2)Tl4 tetrahedra and edges with two equivalent O(4)Tl2Os2 tetrahedra. In the third O site, O(9) is bonded in a 4-coordinate geometry to two equivalent Os(1) and two equivalent Tl(1) atoms. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent Os(1) and two equivalent Tl(2) atoms. In the fifth O site, O(2) is bonded to two equivalent Tl(1) and two equivalent Tl(2) atoms to form OTl4 tetrahedra that share corners with two equivalent O(4)Tl2Os2 tetrahedra and corners with two equivalent O(8)Tl4 tetrahedra. In the sixth O site, O(3) is bonded in a 4-coordinate geometry to one Os(1), one Os(2), one Tl(1), and one Tl(2) atom. In the seventh O site, O(4) is bonded to two equivalent Os(2) and two equivalent Tl(1) atoms to form a mixture of distorted corner and edge-sharing OTl2Os2 tetrahedra. In the eighth O site, O(5) is bonded in a distorted bent 150 degrees geometry to two equivalent Os(2) and two equivalent Tl(2) atoms. In the ninth O site, O(6) is bonded in a 4-coordinate geometry to two equivalent Os(2) and two equivalent Tl(2) atoms.