CHIRAL SUPRAMOLECULAR SELF-ASSEMBLY OF 2,2':6',2-TERPYRIDINE-4'-CARBOXYLIC ACID MOLECULES CHEMICALLY ADSORBED ON Cu(111)

In this paper, large-area chiral supramolecular self-assembly of 2,2':6',2-terpyridine-4'-carboxylic acid (C16H11N3O2; Y) molecules on Cu(111) is studied using scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. The basic building blocks of such a self-assembled monolayer are triangular vortex-shaped supramolecular structures containing three twisted Y molecules. Chirality is maintained and transferred from one vortex to the adjacent vortex in successive molecular domains within the same atomic terrace. The twisted Y molecule, bridging two nearest-neighbor Cu atoms, is stabilized by symmetric Cu-O bonds on the surface. The near perpendicularity of these bonds to the surface is the main reason for the formation of standing-up Y molecules.