Adsorption and Intermolecular Interaction of Cobalt Phthalocyanine on CoO(111) Ultrathin Films: An STM and DFT Study

详细信息    查看全文

• 作者：Tobias Schmitt ; Pascal Ferstl ; Lutz Hammer ; M. Alexander SchneiderJosef Redinger
• 刊名：Journal of Physical Chemistry C
• 出版年：2017
• 出版时间：February 9, 2017
• 年：2017
• 卷：121
• 期：5
• 页码：2889-2895
• 全文大小：611K
• ISSN：1932-7455

文摘

We investigate the adsorption of cobalt phthalocyanine (CoPc) molecules on a thin layer of cobalt oxide grown on Ir(100). To that end we compare the results of low-temperature scanning tunneling microscopy (STM) with those of ab initio density functional theory (DFT) calculations and reveal the adsorption geometry. We find that the CoPc molecules lie flat on the surface and that their central cobalt atom forms a chemical bond to a substrate oxygen ion. However, this bond contributes only modestly to the adsorption energy, while van der Waals forces dominate the potential landscape and determine to a large extent the geometry as well as the distortion of substrate and molecule. Furthermore, they lead to attractive molecule–molecule interactions at higher molecular coverages. The DFT calculations predict energetic positions of the molecular orbitals, which are compared to scanning tunneling spectroscopy (STS) measurements.