Selective adsorption of DHTAP on the nanostructured Cu-CuO stripe phase
Sprache des Vortragstitels:
Annual Meeting of Swiss and Austrian Physical Society 2023
Sprache des Tagungstitel:
We have studied 5,14-dihydro-5,7,12,14-tetraazapentacene (DHTAP) layers on the regularly patterned Cu(110)-(2x1)O stripe phase. Using Reflectance Difference Spectroscopy (RDS) and Scanning Tunneling Microscopy (STM) we find that the DHTAP molecules preferentially adsorb on the Cu(110) stripes, with their long molecular axis aligned parallel to the [-110]-direction. In contrast, on the subsequently covered Cu(110)-(2x1)O stripes, the DHTAP molecules are aligned parallel to the -direction. The evolution of the RDS signal allows to monitor the sequential adsorption and orientation of DHTAP for different oxygen pre-coverages and, hence, different Cu and CuO stripe widths. Interestingly, beyond the first monolayer, the DHTAP molecules adopt a preferential orientation which critically depends on the initial oxygen coverage.