SrIrIn 6 – An Intergrowth of SrIrIn 4 with Indium Slabs

The indium‐rich intermetallic compound SrIrIn 6 was synthesized from the elements in a sealed tantalum ampoule at 1173 K, followed by slow cooling for crystal growth. SrIrIn 6 crystallizes with a new structure type which was characterized by X‐ray powder and single crystal diffraction: Pmma, a = 852.34(2), b = 434.54(5), c = 1059.18(6) pm, wR 2 = 0.0178, 884 F 2 values, and 32 variables. The SrIrIn 6 structure shows two basic building units: (i) Ir@In 9 tricapped trigonal prisms (261–292 pm Ir–In) and (ii) distorted bcc In@In 8 cubes (301 to 329 pm In–In). The strontium cations fill cages within the complex three‐dimensional [IrIn 6 ] network and have coordination number 13 (Sr@In 13 ) in form of a tricapped pentagonal prism. The SrIrIn 6 structure can be described as a simple intergrowth variant of SrIrIn 4 (LaCoAl 4 type) with indium slabs. The crystal chemical similarities with the structures of SrIrIn 4 , SrIr 2 In 8 and Eu 3 Ir 2 In 15 are discussed.