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

In this Communication, we describe a high-resolution STM study on the self-assembly of different alkyl-substituted PTTPs at the graphite–solution interface. By investigating the competitive adsorption among three similar derivatives simultaneously present in an equimolar mixture in the super- natant solution, we provide direct insight into the thermo- dynamics of physisorption at the solid–liquid interface. Molecular-modeling simulations provide an atomistic picture of the assembly of molecules on graphite and a quantitative estimation of the energetics of the physisorption process.