Molecular capsules based on p-sulfonatocalix[6]arene shrouding two tetraphenylphosphonium cations

p-Sulfonatocalix[6]arene in the double cone conformation forms a molecular capsule-like arrangement confining two tetraphenylphosphonium cations, as part of an extended structure involving layers of additional tetraphenylphosphonium cations, aquated lanthanide ions and a large array of water molecules.