Dipole–Dipole Interactions in TiOPc Adlayers on Ag

Autor: Janice Reutt-Robey, Steven W. Robey, Yinying Wei, Xianjie Liu
Rok vydání: 2014
Předmět:
Zdroj: The Journal of Physical Chemistry C. 118:3523-3532
ISSN: 1932-7455
1932-7447
DOI: 10.1021/jp4096612
Popis: The molecular organization of a polar phthalocyanine, titanyl phthalocyanine (TiOPc), on the Ag(110) surface was studied with scanning tunneling microscopy (STM). In addition to the intermolecular hydrogen bonding and electrostatic interactions that guide structure for nonpolar Pc’s, we find evidence for the impact of dipole interactions on layer organization for TiOPc/Ag(110). TiOPc molecules adsorb on Ag(110) with a tilted orientation that contrasts with the flat-lying orientation typically observed for nonpolar phthalocyanines. At the highest TiOPc coverages, the layer consists of neighboring TiOPc molecules with opposing molecular tilts. Close inspection reveals a higher level organization, consisting of “zigzag” TiOPc molecular chains with molecular spacings along the chain that are smaller than the average within the layer. We suggest an explanation for this behavior based on the dipole–dipole interactions within the chain. At reduced coverage, variable densities of molecular vacancies form, dependi...
Databáze: OpenAIRE