Efficient packing of long flexible bis-imidazolium cations in the ubiquitous bilayers of their p-sulfonatocalixarene salts

Long flexible bis-imidazolium dications form discrete multi-component complexes with anionic p-sulfonatocalix[4]arene, cationic tetraphenylphosphonium, and hydrated lanthanide ions (La³⁺ and Gd³⁺). The terminally charged head groups of the dications reside in either one or two calixarene cavities of different bilayers depending on the length of the terminal alkyl group with the central spacer penetrating across the multi-layers and adjusted to fit in the tight bilayer.