Polycrystalline bicyclic di-iron cryptates with different mobile guest cations were synthesized and characterized by X-ray diffraction analysis, IR spectroscopy, FAB-mass spectroscopy, elemental analysis, electrical conductivity spectroscopy and ion exchange experiments. Strong indications were found that the guest cations exhibited a long-range mobility and that their mobility was governed by their size relative to the size of the cryptand molecules. On the other hand, the valence of the guest cations seemed to play a minor role in mobility. These results were considered in comparison to the properties of conventional solid cationic conductors.

Bicyclic Diironcryptates with Mobile Guest Cations - a New Class of Solid Ionic Conductors. R.Puchta, B.Roling, A.Scheurer, V.Weiskopf, F.Hampel, N.J.R.van E.Hommes, H.U.Hummel: Solid State Ionics, 2008, 179[13-14], 489-94