Two-Dimentiaonal Nanofabrication of Phenanthrene Deriatives With Different Substituted Groups At The Liquid/Solid Interface
The self-assembly of two kinds of phenanthrene deriatives (P-2O and P-2OH) with two carbonyl groups and two hydroxyl groups are investigated by using scanning tunneling microscopy (STM), respectively. STM images show that these two kinds of molecules self-assembly into linear patterns at the liquid/solid interface on graphite. Two conjugated cores of P-2O molecules in each trough pack almost in face-to-face fashion, in which the intermolecular van der Waals interactions resulting from the interdigitated side chains are the dominated forces to stabilize the nanostructure. In the adlayer of P-2OH, the conjugated cores in each trough connect each other to form the zigzag linear pattern, owing to the intermolecular hydrogen bonds between the hydroxyl groups. These observation demonstrate that a slight modification of the molecular chemical structure can drastically affect the final self-assembled patterns of 2D hydrogen-bonded adlayers. Keywords- Scanning tunneling microscopy, Self-assembly, Hydrogen bond, Phenanthene.