Two forms (polymorphs) of BeI2 are known. Both structures consist tetrahedral Be2+ centers interconnected by doubly bridging iodide ligands. One form consist of edge-sharing polytetrahedra. The other form resembles zinc iodide with interconnected adamantane-like cages.[4]
Applications
Beryllium iodide can be used in the preparation of high-purity beryllium by the decomposition of the compound on a hot tungsten filament.