Ba7Ir6O19 crystallizes in the monoclinic C2/m space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent O(1), two equivalent O(2), four equivalent O(5), and four equivalent O(7) atoms to form BaO12 cuboctahedra that share corners with two equivalent Ba(1)O12 cuboctahedra, corners with six equivalent Ir(1)O6 octahedra, faces with six equivalent Ba(4)O12 cuboctahedra, faces with two equivalent Ir(2)O6 octahedra, and faces with four equivalent Ir(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-17°. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to two equivalent O(3), two equivalent O(4), two equivalent O(5), and four equivalent O(6) atoms. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to two equivalent O(3), two equivalent O(4), two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms. In the fourth Ba site, Ba(4) is bonded to one O(1), two equivalent O(5), two equivalent O(6), three equivalent O(2), and four equivalent O(7) atoms to form distorted BaO12 cuboctahedra that share corners with three equivalent Ba(4)O12 cuboctahedra,  a cornercorner with one Ir(2)O6 octahedra, corners with two equivalent Ir(3)O6 octahedra, faces with two equivalent Ba(4)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Ir(2)O6 octahedra, faces with two equivalent Ir(3)O6 octahedra, and faces with three equivalent Ir(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-14°. There are three inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to one O(2), one O(3), two equivalent O(6), and two equivalent O(7) atoms to form IrO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(4)O12 cuboctahedra,  a faceface with one Ir(2)O6 octahedra, and  a faceface with one Ir(3)O6 octahedra. In the second Ir site, Ir(2) is bonded to one O(2), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form IrO6 octahedra that share  a cornercorner with one Ba(4)O12 cuboctahedra, corners with two equivalent Ir(3)O6 octahedra,  a faceface with one Ba(1)O12 cuboctahedra, faces with two equivalent Ba(4)O12 cuboctahedra, and  a faceface with one Ir(1)O6 octahedra. The corner-sharing octahedral tilt angles are 14°. In the third Ir site, Ir(3) is bonded to one O(1), one O(3), two equivalent O(5), and two equivalent O(7) atoms to form IrO6 octahedra that share corners with two equivalent Ba(4)O12 cuboctahedra,  a cornercorner with one Ir(3)O6 octahedra, corners with two equivalent Ir(2)O6 octahedra, faces with two equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Ba(4)O12 cuboctahedra, and  a faceface with one Ir(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. There are seven inequivalent O sites. In the first O site, O(5) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Ir(2), and one Ir(3) atom. In the second O site, O(6) is bonded in a 6-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(2), one Ir(1), and one Ir(2) atom. In the third O site, O(7) is bonded to one Ba(1), one Ba(3), two equivalent Ba(4), one Ir(1), and one Ir(3) atom to form distorted OBa4Ir2 octahedra that share  a cornercorner with one O(3)Ba4Ir2 octahedra, corners with two equivalent O(1)Ba4Ir2 octahedra, corners with four equivalent O(7)Ba4Ir2 octahedra, corners with two equivalent O(4)Ba4Ir trigonal bipyramids,  an edgeedge with one O(7)Ba4Ir2 octahedra,  a faceface with one O(1)Ba4Ir2 octahedra,  a faceface with one O(3)Ba4Ir2 octahedra, and faces with two equivalent O(7)Ba4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the fourth O site, O(1) is bonded to two equivalent Ba(1), two equivalent Ba(4), and two equivalent Ir(3) atoms to form a mixture of distorted corner and face-sharing OBa4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 0-59°. In the fifth O site, O(2) is bonded in a 6-coordinate geometry to one Ba(1), three equivalent Ba(4), one Ir(1), and one Ir(2) atom. In the sixth O site, O(3) is bonded to two equivalent Ba(2), two equivalent Ba(3), one Ir(1), and one Ir(3) atom to form distorted OBa4Ir2 octahedra that share  a cornercorner with one O(1)Ba4Ir2 octahedra, corners with two equivalent O(3)Ba4Ir2 octahedra, corners with two equivalent O(7)Ba4Ir2 octahedra,  an edgeedge with one O(3)Ba4Ir2 octahedra, edges with four equivalent O(4)Ba4Ir trigonal bipyramids, and faces with two equivalent O(7)Ba4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 4-53°. In the seventh O site, O(4) is bonded to two equivalent Ba(2), two equivalent Ba(3), and one Ir(2) atom to form distorted OBa4Ir trigonal bipyramids that share corners with four equivalent O(7)Ba4Ir2 octahedra, corners with two equivalent O(4)Ba4Ir trigonal bipyramids, edges with four equivalent O(3)Ba4Ir2 octahedra, and  an edgeedge with one O(4)Ba4Ir trigonal bipyramid. The corner-sharing octahedral tilt angles range from 43-63°.
Ba7Ir6O19 crystallizes in the monoclinic C2/m space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent O(1), two equivalent O(2), four equivalent O(5), and four equivalent O(7) atoms to form BaO12 cuboctahedra that share corners with two equivalent Ba(1)O12 cuboctahedra, corners with six equivalent Ir(1)O6 octahedra, faces with six equivalent Ba(4)O12 cuboctahedra, faces with two equivalent Ir(2)O6 octahedra, and faces with four equivalent Ir(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-17°. Both Ba(1)-O(1) bond lengths are 2.89 Å. Both Ba(1)-O(2) bond lengths are 3.05 Å. All Ba(1)-O(5) bond lengths are 2.81 Å. All Ba(1)-O(7) bond lengths are 2.97 Å. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to two equivalent O(3), two equivalent O(4), two equivalent O(5), and four equivalent O(6) atoms. There is one shorter (2.81 Å) and one longer (2.99 Å) Ba(2)-O(3) bond length. Both Ba(2)-O(4) bond lengths are 2.95 Å. Both Ba(2)-O(5) bond lengths are 3.04 Å. There are two shorter (2.73 Å) and two longer (2.94 Å) Ba(2)-O(6) bond lengths. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to two equivalent O(3), two equivalent O(4), two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms. Both Ba(3)-O(3) bond lengths are 2.91 Å. There is one shorter (2.63 Å) and one longer (2.70 Å) Ba(3)-O(4) bond length. Both Ba(3)-O(5) bond lengths are 3.14 Å. Both Ba(3)-O(6) bond lengths are 2.95 Å. Both Ba(3)-O(7) bond lengths are 2.78 Å. In the fourth Ba site, Ba(4) is bonded to one O(1), two equivalent O(5), two equivalent O(6), three equivalent O(2), and four equivalent O(7) atoms to form distorted BaO12 cuboctahedra that share corners with three equivalent Ba(4)O12 cuboctahedra,  a cornercorner with one Ir(2)O6 octahedra, corners with two equivalent Ir(3)O6 octahedra, faces with two equivalent Ba(4)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Ir(2)O6 octahedra, faces with two equivalent Ir(3)O6 octahedra, and faces with three equivalent Ir(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-14°. The Ba(4)-O(1) bond length is 2.96 Å. Both Ba(4)-O(5) bond lengths are 2.85 Å. Both Ba(4)-O(6) bond lengths are 3.14 Å. All Ba(4)-O(2) bond lengths are 2.90 Å. There are two shorter (2.87 Å) and two longer (3.00 Å) Ba(4)-O(7) bond lengths. There are three inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to one O(2), one O(3), two equivalent O(6), and two equivalent O(7) atoms to form IrO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(4)O12 cuboctahedra,  a faceface with one Ir(2)O6 octahedra, and  a faceface with one Ir(3)O6 octahedra. The Ir(1)-O(2) bond length is 2.01 Å. The Ir(1)-O(3) bond length is 2.10 Å. Both Ir(1)-O(6) bond lengths are 2.05 Å. Both Ir(1)-O(7) bond lengths are 2.04 Å. In the second Ir site, Ir(2) is bonded to one O(2), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form IrO6 octahedra that share  a cornercorner with one Ba(4)O12 cuboctahedra, corners with two equivalent Ir(3)O6 octahedra,  a faceface with one Ba(1)O12 cuboctahedra, faces with two equivalent Ba(4)O12 cuboctahedra, and  a faceface with one Ir(1)O6 octahedra. The corner-sharing octahedral tilt angles are 14°. The Ir(2)-O(2) bond length is 2.10 Å. The Ir(2)-O(4) bond length is 2.00 Å. Both Ir(2)-O(5) bond lengths are 2.00 Å. Both Ir(2)-O(6) bond lengths are 2.04 Å. In the third Ir site, Ir(3) is bonded to one O(1), one O(3), two equivalent O(5), and two equivalent O(7) atoms to form IrO6 octahedra that share corners with two equivalent Ba(4)O12 cuboctahedra,  a cornercorner with one Ir(3)O6 octahedra, corners with two equivalent Ir(2)O6 octahedra, faces with two equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Ba(4)O12 cuboctahedra, and  a faceface with one Ir(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. The Ir(3)-O(1) bond length is 2.05 Å. The Ir(3)-O(3) bond length is 2.06 Å. Both Ir(3)-O(5) bond lengths are 2.01 Å. Both Ir(3)-O(7) bond lengths are 2.04 Å. There are seven inequivalent O sites. In the first O site, O(5) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Ir(2), and one Ir(3) atom. In the second O site, O(6) is bonded in a 6-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(2), one Ir(1), and one Ir(2) atom. In the third O site, O(7) is bonded to one Ba(1), one Ba(3), two equivalent Ba(4), one Ir(1), and one Ir(3) atom to form distorted OBa4Ir2 octahedra that share  a cornercorner with one O(3)Ba4Ir2 octahedra, corners with two equivalent O(1)Ba4Ir2 octahedra, corners with four equivalent O(7)Ba4Ir2 octahedra, corners with two equivalent O(4)Ba4Ir trigonal bipyramids,  an edgeedge with one O(7)Ba4Ir2 octahedra,  a faceface with one O(1)Ba4Ir2 octahedra,  a faceface with one O(3)Ba4Ir2 octahedra, and faces with two equivalent O(7)Ba4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the fourth O site, O(1) is bonded to two equivalent Ba(1), two equivalent Ba(4), and two equivalent Ir(3) atoms to form a mixture of distorted corner and face-sharing OBa4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 0-59°. In the fifth O site, O(2) is bonded in a 6-coordinate geometry to one Ba(1), three equivalent Ba(4), one Ir(1), and one Ir(2) atom. In the sixth O site, O(3) is bonded to two equivalent Ba(2), two equivalent Ba(3), one Ir(1), and one Ir(3) atom to form distorted OBa4Ir2 octahedra that share  a cornercorner with one O(1)Ba4Ir2 octahedra, corners with two equivalent O(3)Ba4Ir2 octahedra, corners with two equivalent O(7)Ba4Ir2 octahedra,  an edgeedge with one O(3)Ba4Ir2 octahedra, edges with four equivalent O(4)Ba4Ir trigonal bipyramids, and faces with two equivalent O(7)Ba4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 4-53°. In the seventh O site, O(4) is bonded to two equivalent Ba(2), two equivalent Ba(3), and one Ir(2) atom to form distorted OBa4Ir trigonal bipyramids that share corners with four equivalent O(7)Ba4Ir2 octahedra, corners with two equivalent O(4)Ba4Ir trigonal bipyramids, edges with four equivalent O(3)Ba4Ir2 octahedra, and  an edgeedge with one O(4)Ba4Ir trigonal bipyramid. The corner-sharing octahedral tilt angles range from 43-63°.