(Benzophenone)9(KI)2I7, CHCl3 single crystals have a golden metallic reflection on the surfaces parallel to the polyiodine chain axis. The compound is a member of a large class of channel-like inclusion compounds in which isolated iodine atom chains are the only possible conducting strands in an otherwise insulating matrix. The (contactless) microwave conductivity is ∼ 10 Ω−1 cm−1 at room temperature with an activation energy of ∼0.03 eV down to 70°K, while the dc conductivity is ∼10−-6. Conductivity is strongly frequency dependent and contact problems are severe.
Molecular crystals and liquid crystals 52(1), pp.115-120