Molecular recognition of PTCDI-C8 molecules on the Si(1 1 0)-(16 × 2) surface

Mechanisms of PTCDI-C8 adsorption and thin films growth on Si(1 1 0)-(16 × 2) have been studied using a combination of X-ray photoelectron spectroscopy, scanning tunneling microscopy, and density functional theory. Oxygen atoms of the PTCDI-C8 molecule interact with the substrate increasing substantially the adsorption energy. Adsorbed molecules do not form long-range ordered structures on the surface but local chain-like arrangements. A good agreement between the calculated isosurfaces of electronic charge density and the scanning tunneling microscopy images of the filled electron states of clean and adsorbate-covered surfaces allows to recognize the PTCDI-C8 molecules adsorbed on Si(1 1 0)-(16 × 2).