Figure 3.
The adsorption geometries of CuPc molecules on the TiO2(011) substrate (coverage: 0.06 ML): (a) a submolecularly resolved empty-state STM image, (the squares are molecules adsorbed on oxygen zigzag rows, and the circles are molecules adsorbed in between the zigzag rows), (b) a schematic illustration of stable adsorption geometries on terraces, (c) a schematic image of a CuPc molecule and two orbitals forming the LUMO, (d) STM images of molecules exhibiting two-fold symmetry and their schematic illustration, (e) a schematic illustration of the STM appearance of a CuPc molecule. All scans: bias voltage 2.0 V, tunnelling current 2 pA. Colour coding: white – mobile molecules, green – molecules located at the step edges, black and blue – different azimuthal angle of the molecules. The figure has been adapted with permission from [33], copyright 2011 AIP Publishing LLC.