Cs3IrOBr6 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 10-coordinate geometry to one Br(4), two equivalent Br(3), three equivalent Br(2), and four equivalent Br(1) atoms. In the second Cs site, Cs(2) is bonded in a 10-coordinate geometry to two equivalent O(1), two equivalent Br(1), two equivalent Br(4), and four equivalent Br(3) atoms. In the third Cs site, Cs(3) is bonded in a 8-coordinate geometry to one O(1), one Br(2), two equivalent Br(1), two equivalent Br(3), and two equivalent Br(4) atoms. Ir(1) is bonded in an octahedral geometry to one Br(2), one Br(4), two equivalent Br(1), and two equivalent Br(3) atoms. O(1) is bonded in a single-bond geometry to one Cs(3) and two equivalent Cs(2) atoms. There are four inequivalent Br sites. In the first Br site, Br(4) is bonded to one Cs(1), two equivalent Cs(2), two equivalent Cs(3), and one Ir(1) atom to form distorted BrCs5Ir octahedra that share corners with four equivalent Br(4)Cs5Ir octahedra, corners with four equivalent Br(1)Cs4Ir square pyramids, corners with two equivalent Br(2)Cs4Ir trigonal bipyramids, edges with two equivalent Br(1)Cs4Ir square pyramids, edges with two equivalent Br(2)Cs4Ir trigonal bipyramids, and faces with two equivalent Br(1)Cs4Ir square pyramids. The corner-sharing octahedral tilt angles range from 10-54°. In the second Br site, Br(1) is bonded to one Cs(2), one Cs(3), two equivalent Cs(1), and one Ir(1) atom to form distorted BrCs4Ir square pyramids that share corners with two equivalent Br(4)Cs5Ir octahedra, corners with two equivalent Br(1)Cs4Ir square pyramids, corners with three equivalent Br(2)Cs4Ir trigonal bipyramids,  an edgeedge with one Br(4)Cs5Ir octahedra, edges with two equivalent Br(1)Cs4Ir square pyramids,  an edgeedge with one Br(2)Cs4Ir trigonal bipyramid,  a faceface with one Br(4)Cs5Ir octahedra,  a faceface with one Br(1)Cs4Ir square pyramid, and  a faceface with one Br(2)Cs4Ir trigonal bipyramid. The corner-sharing octahedral tilt angles range from 37-61°. In the third Br site, Br(2) is bonded to one Cs(3), three equivalent Cs(1), and one Ir(1) atom to form distorted BrCs4Ir trigonal bipyramids that share corners with two equivalent Br(4)Cs5Ir octahedra, corners with six equivalent Br(1)Cs4Ir square pyramids, corners with two equivalent Br(2)Cs4Ir trigonal bipyramids, edges with two equivalent Br(4)Cs5Ir octahedra, edges with two equivalent Br(1)Cs4Ir square pyramids, edges with two equivalent Br(2)Cs4Ir trigonal bipyramids, and faces with two equivalent Br(1)Cs4Ir square pyramids. The corner-sharing octahedral tilt angles range from 0-53°. In the fourth Br site, Br(3) is bonded in a 5-coordinate geometry to one Cs(1), one Cs(3), two equivalent Cs(2), and one Ir(1) atom.
Cs3IrOBr6 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 10-coordinate geometry to one Br(4), two equivalent Br(3), three equivalent Br(2), and four equivalent Br(1) atoms. The Cs(1)-Br(4) bond length is 3.72 Å. Both Cs(1)-Br(3) bond lengths are 3.90 Å. There is one shorter (3.60 Å) and two longer (3.83 Å) Cs(1)-Br(2) bond lengths. There are two shorter (3.66 Å) and two longer (3.87 Å) Cs(1)-Br(1) bond lengths. In the second Cs site, Cs(2) is bonded in a 10-coordinate geometry to two equivalent O(1), two equivalent Br(1), two equivalent Br(4), and four equivalent Br(3) atoms. Both Cs(2)-O(1) bond lengths are 3.83 Å. Both Cs(2)-Br(1) bond lengths are 3.78 Å. There is one shorter (3.64 Å) and one longer (3.89 Å) Cs(2)-Br(4) bond length. There are two shorter (3.79 Å) and two longer (3.81 Å) Cs(2)-Br(3) bond lengths. In the third Cs site, Cs(3) is bonded in a 8-coordinate geometry to one O(1), one Br(2), two equivalent Br(1), two equivalent Br(3), and two equivalent Br(4) atoms. The Cs(3)-O(1) bond length is 3.21 Å. The Cs(3)-Br(2) bond length is 3.68 Å. Both Cs(3)-Br(1) bond lengths are 3.87 Å. Both Cs(3)-Br(3) bond lengths are 3.63 Å. Both Cs(3)-Br(4) bond lengths are 3.83 Å. Ir(1) is bonded in an octahedral geometry to one Br(2), one Br(4), two equivalent Br(1), and two equivalent Br(3) atoms. The Ir(1)-Br(2) bond length is 2.51 Å. The Ir(1)-Br(4) bond length is 2.54 Å. Both Ir(1)-Br(1) bond lengths are 2.52 Å. Both Ir(1)-Br(3) bond lengths are 2.51 Å. O(1) is bonded in a single-bond geometry to one Cs(3) and two equivalent Cs(2) atoms. There are four inequivalent Br sites. In the first Br site, Br(4) is bonded to one Cs(1), two equivalent Cs(2), two equivalent Cs(3), and one Ir(1) atom to form distorted BrCs5Ir octahedra that share corners with four equivalent Br(4)Cs5Ir octahedra, corners with four equivalent Br(1)Cs4Ir square pyramids, corners with two equivalent Br(2)Cs4Ir trigonal bipyramids, edges with two equivalent Br(1)Cs4Ir square pyramids, edges with two equivalent Br(2)Cs4Ir trigonal bipyramids, and faces with two equivalent Br(1)Cs4Ir square pyramids. The corner-sharing octahedral tilt angles range from 10-54°. In the second Br site, Br(1) is bonded to one Cs(2), one Cs(3), two equivalent Cs(1), and one Ir(1) atom to form distorted BrCs4Ir square pyramids that share corners with two equivalent Br(4)Cs5Ir octahedra, corners with two equivalent Br(1)Cs4Ir square pyramids, corners with three equivalent Br(2)Cs4Ir trigonal bipyramids,  an edgeedge with one Br(4)Cs5Ir octahedra, edges with two equivalent Br(1)Cs4Ir square pyramids,  an edgeedge with one Br(2)Cs4Ir trigonal bipyramid,  a faceface with one Br(4)Cs5Ir octahedra,  a faceface with one Br(1)Cs4Ir square pyramid, and  a faceface with one Br(2)Cs4Ir trigonal bipyramid. The corner-sharing octahedral tilt angles range from 37-61°. In the third Br site, Br(2) is bonded to one Cs(3), three equivalent Cs(1), and one Ir(1) atom to form distorted BrCs4Ir trigonal bipyramids that share corners with two equivalent Br(4)Cs5Ir octahedra, corners with six equivalent Br(1)Cs4Ir square pyramids, corners with two equivalent Br(2)Cs4Ir trigonal bipyramids, edges with two equivalent Br(4)Cs5Ir octahedra, edges with two equivalent Br(1)Cs4Ir square pyramids, edges with two equivalent Br(2)Cs4Ir trigonal bipyramids, and faces with two equivalent Br(1)Cs4Ir square pyramids. The corner-sharing octahedral tilt angles range from 0-53°. In the fourth Br site, Br(3) is bonded in a 5-coordinate geometry to one Cs(1), one Cs(3), two equivalent Cs(2), and one Ir(1) atom.