Surface Characterization of N-Heterocyclic Carbenes on Gold and Silver: Exploring Distinct Crystalline Facets.

Due to its exceptional chemical and functional versatility, N-heterocyclic carbene chemistry holds great promise in replacing thiol chemistry for applications in next-generation nanoelectronics. To manipulate their chemical properties and interfacial characteristics, a wide range of substrates needs to be employed for the formation of self-assemblies. Research has, however, predominantly focused on the Au(111) substrate. Herein, a systematic approach is presented for producing long-range, densely packed self-assemblies using carbenes deposited over (111) and (100) crystalline facets of gold and silver single crystals. Atomic-resolution characterization with scanning tunneling microscopy (performed at 78 K and room temperature) is combined with the molecular structure, showing the role of distinct crystal facets in the ordering of self-assembled monolayers.