An inorganic starch–iodine model: the inorganic–organic hybrid compound {(C4H12N2)2[CuII4](I2)}n

The dark-blue crystal color of {(C4H12N2)2[CuII4](I2)}n, its mixture of I−, I3− and linear I42− or linear I5− polyiodide species in a linear channel arrangement, its channel diameter of ∼5.5 Å and the helical arrangement of the hydrogen bonded {(C4H12N2)2[CuII4]}+ supramolecular host around the channels agree with the description of the classical, yet structurally elusive, starch–iodine compound.