Electronic and optical properties in the solid-state molecular assemblies of anion-responsive pyrrole-based π-conjugated systems.

On the basis of the chemistry in solution, the solid-state structures and the corresponding electronic and optical properties of dipyrrolyldiketone boron complexes as π-conjugated acyclic anion receptors have been investigated. Solid-state assemblies of the receptors exhibit anion-dependent properties that are in sharp contrast to those in the solution state. Anion complexation, along with structural differences in the pyrrole subunits such as a benzo-fused pyrrole, plays an essential role not only in the formation of the assembled modes but also in determining electronic and optical properties, as well as the charge-carrier mobilities. In addition, by anion complexation, inclusion of the counter cations into the crystals has also been found to be one of the essential factors to determine the properties.