Self-assembled structures of 4′-([2,2′:6′,2-terpyridine]-4′-yl)-[1,1′-phenyl]-4-carboxylic acid molecules induced by metal atoms on ag (111) surface

The self-assembled supramolecular structures of 4'-([2,2':6',2 ''-terpyridine]-4'-yl)-[1,1'-phenyl]-4-carboxylic acid (Y) molecules on Ag(111) surface induced by metal elements have been studied by scanning tunneling microscopy. After annealing, the as-deposited monolayer of Y molecules shows four kinds of well-ordered structures due to the competition between dipole interaction, hydrogen bonding and Van der Waals interaction. Introduced Cu atoms drive ordered monolayer into a self-assembled supramolecular structure with bright spots. Deposited Ag atoms cause the monolayer change to a windmill shape self-assembled supramolecular structure. Though the Cu and Ag are in the same group of the periodic table, a Cu atom connects two COOH groups and an Ag atom trends to bind to three COOH groups during the formation of metal-organic bonding within both induced structures. Such result suggests that the self-assembled structures formed by metal-organic coordination bonding can be controlled by choosing the number of metal-organic coordination bonds, which can be helpful to design metal-organic molecular architectures comprising functional building blocks. (C) 2016 Elsevier B.V. All rights reserved.