hydrogen-bond and π−ππ−π interactions involving thiourea/urea, imidazoline/imidazole and other groups serving as binding units; organometallic interactions involving metal ion binding sites ; and silyl ether-fluoride interactions. Systems based on silyl ether fluoride interactions have shown significant potential due to the great affinity of silyl groups towards fluoride arising from the large differences between the dissociation energies of Si–O (103 kcal/mol) and Si–F (141 kcal/mol) .