Ge_4.06I, an Unexpected Germanium Subiodide—a Tetragermanioiodonium(III) Iodide with Clathrate Structure [Ge_{46 − x}I_x]I₈, x = 8/3

Upon rapid thermal decomposition of GeI₂—an important reaction for the chemical transport of germanium—the metastable subiodide Ge_4.06I, a semiconductor with a clathrate structure, is formed. The clathrate framework is made up of Ge and I³⁺, and I⁻ ions are present in the cavities: [Ge_46-8/3I_8/3]I₈·Ge_4.06I forms dendrite-like intergrown cubes, as shown in the picture on the right.