Here we present a joint experimental-theoretical study on the deposition of imidazole molecules on a Cu(100) surface. X-ray photoelectron spectroscopy (XPS) and Surface-enhanced Raman spectroscopy (SERS) have been carried out on samples prepared upon deposition of sublimated imidazole molecules in ultra-high vacuum (UHV). Computational studies, performed in the frame of the density functional theory (DFT), include a wide variety of models where the coadsorption of imidazole molecules and dehydrogenated species takes place. The combination of measurements and simulations demonstrates the formation of two types of coating at the metal–organic interface: (i) self-assembled monolayers stabilized through intermolecular hydrogen bonds and (ii) polymeric species with new CC bonds established between the imidazole units.