This article shows that a difference in the building blocks of the molecular framework, C–C to S–S, results in a significant influence on its optical properties. Acyclic anion receptors, bis {2- [3-(substituted) thioureido] ethyl} disulfides were newly synthesized, and their optical properties in response to complex formation with an acetate ion were compared with those of a hexamethylene framework between two thioureido groups. Quantum chemical ...