| AVS 61st International Symposium & Exhibition | |
| Surface Science | Thursday Sessions |
| Session SS+TF-ThM |
| Session: | Organic Layers on Surfaces |
| Presenter: | Charles Ruggieri, Rutgers, the State University of New Jersey |
| Authors: | C. Ruggieri, Rutgers, the State University of New Jersey S. Rangan, Rutgers, the State University of New Jersey R.A. Bartynski, Rutgers, the State University of New Jersey E. Galoppini, Rutgers, the State University of New Jersey |
| Correspondent: | Click to Email |
The interaction between Zinc Tetraphenylporphyrin (ZnTPP) molecules and the Au(111) surface is investigated using scanning tunnel microscopy (STM), from initial adsorption sites to monolayer organization, with a particular emphasis on its relation to the surface atomic structure and reorganization. When adsorbed at room temperature, ZnTPP molecules initially decorate step edges at low coverage. As the coverage approaches 0.5 monolayer (ML), ZnTPP molecules self-organize into islands of molecules in a rectangular array that is in registry with the underlying Au(111) lattice. The molecules are oriented with their macrocycles parallel to the surface, and form islands in areas delimited by herringbone reconstruction domain walls. As the coverage approaches one ML, the adsorption geometry of the self-organized molecular layer can be fully characterized with respect to the atomic structure of Au(111) surface atoms. Moreover, ZnTPP adsorption alters the Au(111) herringbone reconstruction domain size, most likely caused by anisotropic adsorbate-induced surface stress. However, when a monolayer is prepared from desorption of a ZnTPP multilayer, a different molecular organization is observed at the surface. It is proposed that this reconstruction is enabled by the particular reconstruction of the Au(111) surface. In this configuration, the domain size of the Au reconstruction is closer to that of clean Au, due to smaller adsorbate-induced surface stress.