Coadsorbed NTCDI-melamine mixed phases on Ag-Si(111)

The coadsorption of naphthalene tetracarboxylic diimide and melamine (1,3,5-triazine-2,4,6-triamine) on the Ag-Si(111)√3×√3R30° surface has been investigated using scanning tunneling microscopy under ultrahigh vacuum conditions. Three hydrogen bonding arrangements between the constituent molecules are possible, which result in the formation of a variety of supramolecular structures. The primary unit for the formation of larger complex structures such as a triangular and a row arrangement was identified. A comparison with similar molecules which have been studied previously indicates that the molecule-substrate interaction plays an important role in the formation of the observed structures.