An effective strategy to tune supramolecular interaction via a spiro-bridged spacer in oligothiophene-S,S-dioxides and their anomalous photoluminescent behavior.

[structure: see text] We demonstrate that incorporating nonplanar spiro-bridged structures is an effective strategy for tuning supramolecular interactions of optoelectronic functional moieties. In the model compounds spiro-bridged oligothiophene-S,S-dioxides (BSiSDTFO), unusual dimers constructed by spiro-bridged spacers do not form excimers, which is confirmed by crystallographic data and fluorescent emission spectra.