Iodine Clathrated: A Solid‐State Analogue of the Iodine–Starch Complex

Co‐crystallizing iodine with a simple dicationic salt (1,8‐diammoniumoctane chloride) results in the clathration of the iodine (I 2 ) molecules inside trigonal and hexagonal helical channels of the crystal lattice with 72 wt % overall I 2 loading. The I 2 inside the bigger trigonal channel forms a I−I⋅⋅⋅I−I⋅⋅⋅I−I halogen‐bonded infinite helical chain, while the I 2 in the smaller hexagonal channel is disordered. In both channels the I 2 interaction with the channel wall happens through I−I⋅⋅⋅Cl − halogen bonds. The helical channels in the crystal lattice are constructed via the strong charge‐assisted H 2 N + H⋅⋅⋅Cl − hydrogen bonds between the dications and the chloride anions. The structure shows a marked similarity with the well‐known starch–I 2 system, and thus may provide insight for the yet unresolved structure of the I 2 in the helical starch channel.