Construction of molecular self-assembled tessellations on noble metal surfaces by vertex design

The self-assembly and multiple tessellation structures of organic molecules on the metal surface are of great significance for the design of functional materials. Some examples of the manipulation of supramolecular tessellations and the exploration of the impact arising from deliberate modifications of the underlying substrate have been demonstrated on various noble metal substrates. However, due to the effects of varied substrates and molecule coverages, the patterns of molecular tessellations have not been precisely predictable. Here, we utilize scanning tunneling microscopy (STM) and density functional theory (DFT) to study various molecular tessellations on M(111) (M=Ag, Au, Cu) surface through the deliberate modulation of substrate activity, surface coverage, substrate temperature and substrate lattice to change the vertex symmetry. Using 1,2-Di(4-pyridyl) ethylene (BPE) molecule, we obtained seven molecular tessellations, where the intermolecular interaction conversion from the weak hydrogen bond (C-H···N) to the possible metal−organic coordination bond has been analyzed. We identified that the hydrogen bonding through C-H···N plays the predominant role in the BPE patterns on Au(111) and Ag(111), while the participation of Cu adatoms plays the important role for the intermolecular interactions through Cu−N interaction in the BPE patterns on Cu(111).