Competitive Physisorption Among Alkyl-Substituted π-Conjugated Oligomers at the Solid-Liquid Interface: Towards Prediction of Self-Assembly at Surfaces from a Multicomponent Solution

The in-situ STM studies of the self assembly of PTTP derivatives at the solution graphite interface revealed that subtle changes in the nature of alkyl side-groups drives the 2D packing towards motifs featuring either interdigitation or noninterdigitation of neighboring alkyl chains. The study has provided a direct insight into the thermodynamics of physisorption at the solid-liquid interface. The PTTP derivatives were synthesized by preparing the solution in 1-phenyloctane at different concentrations showing no formation of aggregates and ensuring the saturation of concentration at room temperature. The results predicted the 2D self-assembly at the solid-liquid interface from a multicomponent solution with a precise control over concentration to extract accurate numbers required with some improvements in terms of the instrumental apparatus.