Charge-Promoted Self-Metalation of Porphyrins on an Oxide Surface.
Larissa EggerMichael HollererChristian S KernHannes HerrmannPhilipp HurdaxAnja HaagsXiaosheng YangAlexander GottwaldMathias RichterSerguei SoubatchF Stefan TautzGeorg KollerPeter PuschnigMichael G RamseyMartin SterrerPublished in: Angewandte Chemie (International ed. in English) (2021)
Metalation and self-metalation reactions of porphyrins on oxide surfaces have recently gained interest. The mechanism of porphyrin self-metalation on oxides is, however, far from being understood. Herein, we show by a combination of results obtained with scanning tunneling microscopy, photoemission spectroscopy, and DFT computations, that the self-metalation of 2H-tetraphenylporphyrin on the surface of ultrathin MgO(001) films is promoted by charge transfer. By tuning the work function of the MgO(001)/Ag(001) substrate, we are able to control the charge and the metalation state of the porphyrin molecules on the surface.