Molecular Organization of Bis-urea Substituted Thiophene Derivatives at the Liquid/Solid Interface Studies by Scanning Teunneling Microscopy

摘要

In this contribution we report on a structural investigation of the two-dimensional (2D) supramolecular organization of three bis-urea substituted thiophene derivatives, containing one, two, or three thiophene , units, at the solution/graphite interface with scanning tunneling microscopy (STM), The compounds under investigation form highly ordered physisorbedmonolayers, It is found that hydrogen bonding between the urea groups of adjacent molecules controls the spatial arrangement on the graphite surface, Molecular modeling and theoretical calculations demonstrate that the thiophene rings are tilted with r~spect to the surface and have partially overlapping ;r-systems, This control of the 2D self-assembly is promising fOI future studies on the electronic properties of these molecules.