Electrical-Pulse-Induced Mixture and Separation in Surface Supramolecular Hybrids: STM Experiments and Theoretical Approaches

Using scanning tunneling microscopy (STM) we investigated the effect of electrical pulses upon a supramolecular hybrid comprised of pentacenes and 1,3,5-tris(4-carboxyphenyl)benzenes at the octanoic acid/graphite interface. STM results revealed that positive electrical pulses can promote the formation of such hybrids, whereas negative pulses selectively remove pentacene molecules from the complex. We attribute such results to the voltage-pulse-induced instant electrical attraction and repulsion between pentacene and substrate, thereby inducing the hybrid to form or to deform, respectively. Furthermore, these observed phenomena were elucidated via a coarse-grained molecular dynamic model using the continuum approximation.