Large-extended 2D supramolecular network of dipoles with parallel arrangement on a Si(111)–B surface. Issue 33 (13th August 2020) - Custovic, Irma
Abstract : We successfully formed a 2D supramolecular network of a molecule with large dipole on Si(111)–B. The balance among molecule–molecule and molecule–surface interactions favors the highly homogeneous parallel arrangement of the dipoles on the surface. Abstract : We have investigated the self-assembly of a strong dipolar molecule (LDipCC) on the semiconducting Si(111)–B surface with scanning tunneling microscopy (STM), density functional theory (DFT) calculations and STM simulations. Although the formation of an extended two-dimensional network was clearly revealed by STM under ultra-high vacuum, the assignment of a specific STM signature to the different terminal groups from the LDipCC molecular unit required a complete analysis by numerical simulations. The overall observed assembly is explained in terms of STM contrasts associated with the molecular structure of LDipCC and the molecule–surface interactions. To distinguish the relative arrangement of the dipolar molecules within the assembly, a rational combination of experimental results and electronic structure calculations allows us to identify a single adsorbed LDipCC phase in which the molecular dipoles are homogeneously arranged into a parallel fashion on the Si(111)–B surface.