CuPc Adsorption on Au(110)-(1 × 2): From a Monomer to a Periodic Chain

Abstract

Using scanning tunneling microscopy (STM), we study the adsorption of copper-phthalocyanine (CuPc) on the anisotropic Au(110)-(1 × 2) surface as a function of coverage. For the initial adsorption at room temperature, we observe CuPc monomers as well as a molecular chain that forms along the step edge. By STM manipulation, we reveal that the CuPc adsorption is accompanied by surface reconstruction from the initial adsorption stage; the periodicity beneath the monomer and the chain changes locally from (1 × 2) to (1 × 1) and (1 × 3), respectively. This finding highlights that the Au atom mobility of the surface plays an essential role in CuPc adsorption. At higher coverage, we observe the development of CuPc chains along the [110] direction on the terrace with periodicities of (7 × 5) and (5 × 5), and compare the obtained results with those from the previous studies by diffraction methods.