One-dimensional (1-D) nanostructured organic materials such as conducting polymers are low-cost, scalable, environmentally friendly, and possess flexible and tunable electrical, optical, and mechanical properties. They have attracted a great amount of attention in recent years due to their potential for replacing their inorganic counterparts in various electronics and optoelectronics. However, the lack of order at the molecular chain level hinders conducting polymers such as polyaniline from realizing their full potential in practical devices that require high carrier mobility and stability. This is mostly due to the coiled nature of the polymer chains which results in the poor interchain transport in a bulk film. Optimizing such factors to achieve high conductivity have been challenging as the long, coiled polymer chains are difficult to isolate and manipulate. In contrast to the polymer, conducting oligomers such as the oligoanilines are capable of forming extended ordered structures as their small size and molecular rigidity resemble small conjugated molecule conductors. Therefore, conducting oligomers serve as a unique middle ground between the parent polymer and molecular conductors. Here we investigate the crystal structure and electrical properties of the smallest "polyaniline" aniline tetramer. It contains 3 benzenoid rings and 1 quinoid ring in its doped emeraldine salt oxidation state, which is the building block for polyaniline in its conductive oxidation state.
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