Conformational Adaptation and Electronic Structure of 2H-Tetraphenylporphyrin on Ag(111) during Fe Metalation

In-situ metalation of porphyrin molecules in ultrahigh vacuum (UHV) is of great interest for the characterization of pure species in a controlled environment Here, we report the characterization of the electronic states and the molecules' geometrical adaptation during the formation of pure 2H-5,10,15,20-tetraphenylporphyrin (2H-TPP) and Fe- tetraphenylporphyrin (Fe-TPP) layers on Ag(111) single crystal. Core level absorption spectra indicate the flat conformation of the monolayer suggesting an adatom hopping instead of a surface mediated dopant diffusion for the metalation process. Photoemission points out that the interaction between Fe d(z)-states and Ag, bands increases the monolayer metallic character already induced by the charge transfer from the substrate.