Understanding of molecular assembly with scanning tunneling microscopy at solid/liquid interfaces

Scanning tunneling microscopy (STM) was used to resolve molecular packing structures of mixed thiophene-N-alkylpyrrole oligomeric molecules at the solid/liquid interfaces. We have systematically synthesized several mixed thiophene-pyrrole oligomers to understand the nature of grains, shapes, and crystalline orientations. The resulting STM images were compared with the structure generated by MM3 molecular modeling simulation. The basal plane of highly oriented pyrolytic graphite (HOPG) surface was used to deposit the molecules.