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 character- ization 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- tetra- phenylporphyrin (Fe-TPP) layers on Ag(111) single crystal. Core level absorption spectra indicate the _at conformation of the monolayer suggesting an adatom hopping instead of a surface mediated dopant di_usion for the metalation process. Photoemission points out that the interaction between Fe dz-states and Ag bands increases the monolayer metallic character already induced by the charge transfer from the substrate.