Ir3Se is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to four equivalent Ir(1), four equivalent Ir(2), and four equivalent Se(1) atoms to form distorted IrIr8Se4 cuboctahedra that share corners with twelve equivalent Ir(1)Ir8Se4 cuboctahedra, edges with eight equivalent Ir(1)Ir8Se4 cuboctahedra, edges with eight equivalent Ir(2)Ir8Se4 cuboctahedra, edges with eight equivalent Se(1)Ir12 cuboctahedra, faces with four equivalent Ir(2)Ir8Se4 cuboctahedra, faces with four equivalent Se(1)Ir12 cuboctahedra, and faces with ten equivalent Ir(1)Ir8Se4 cuboctahedra. In the second Ir site, Ir(2) is bonded to eight equivalent Ir(1) and four equivalent Se(1) atoms to form IrIr8Se4 cuboctahedra that share corners with four equivalent Ir(2)Ir8Se4 cuboctahedra, corners with eight equivalent Se(1)Ir12 cuboctahedra, edges with eight equivalent Ir(2)Ir8Se4 cuboctahedra, edges with sixteen equivalent Ir(1)Ir8Se4 cuboctahedra, faces with four equivalent Ir(2)Ir8Se4 cuboctahedra, faces with six equivalent Se(1)Ir12 cuboctahedra, and faces with eight equivalent Ir(1)Ir8Se4 cuboctahedra. Se(1) is bonded to four equivalent Ir(2) and eight equivalent Ir(1) atoms to form SeIr12 cuboctahedra that share corners with four equivalent Se(1)Ir12 cuboctahedra, corners with eight equivalent Ir(2)Ir8Se4 cuboctahedra, edges with eight equivalent Se(1)Ir12 cuboctahedra, edges with sixteen equivalent Ir(1)Ir8Se4 cuboctahedra, faces with four equivalent Se(1)Ir12 cuboctahedra, faces with six equivalent Ir(2)Ir8Se4 cuboctahedra, and faces with eight equivalent Ir(1)Ir8Se4 cuboctahedra.
Ir3Se is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to four equivalent Ir(1), four equivalent Ir(2), and four equivalent Se(1) atoms to form distorted IrIr8Se4 cuboctahedra that share corners with twelve equivalent Ir(1)Ir8Se4 cuboctahedra, edges with eight equivalent Ir(1)Ir8Se4 cuboctahedra, edges with eight equivalent Ir(2)Ir8Se4 cuboctahedra, edges with eight equivalent Se(1)Ir12 cuboctahedra, faces with four equivalent Ir(2)Ir8Se4 cuboctahedra, faces with four equivalent Se(1)Ir12 cuboctahedra, and faces with ten equivalent Ir(1)Ir8Se4 cuboctahedra. All Ir(1)-Ir(1) bond lengths are 2.85 Å. All Ir(1)-Ir(2) bond lengths are 2.76 Å. All Ir(1)-Se(1) bond lengths are 2.76 Å. In the second Ir site, Ir(2) is bonded to eight equivalent Ir(1) and four equivalent Se(1) atoms to form IrIr8Se4 cuboctahedra that share corners with four equivalent Ir(2)Ir8Se4 cuboctahedra, corners with eight equivalent Se(1)Ir12 cuboctahedra, edges with eight equivalent Ir(2)Ir8Se4 cuboctahedra, edges with sixteen equivalent Ir(1)Ir8Se4 cuboctahedra, faces with four equivalent Ir(2)Ir8Se4 cuboctahedra, faces with six equivalent Se(1)Ir12 cuboctahedra, and faces with eight equivalent Ir(1)Ir8Se4 cuboctahedra. All Ir(2)-Se(1) bond lengths are 2.85 Å. Se(1) is bonded to four equivalent Ir(2) and eight equivalent Ir(1) atoms to form SeIr12 cuboctahedra that share corners with four equivalent Se(1)Ir12 cuboctahedra, corners with eight equivalent Ir(2)Ir8Se4 cuboctahedra, edges with eight equivalent Se(1)Ir12 cuboctahedra, edges with sixteen equivalent Ir(1)Ir8Se4 cuboctahedra, faces with four equivalent Se(1)Ir12 cuboctahedra, faces with six equivalent Ir(2)Ir8Se4 cuboctahedra, and faces with eight equivalent Ir(1)Ir8Se4 cuboctahedra.