Order, disorder, and metalation of tetraphenylporphyrin (2 H -TPP) on Au(111).

A thermally induced order-disorder transition of tetraphenylporphyrin (2 H -TPP) on Au(111) is characterised by scanning probe microscopy and X-ray photoelectron spectroscopy-based techniques. We observed that a transition from an ordered close-packed phase to a disordered diffuse phase is correlated with an on-surface cyclodehydrogenation reaction, and that additional heating of this diffuse phase gives rise to a single distinct nitrogen environment indicative of the formation of a Au-TPP species.