Conformational molecular architecture in alkylthiolate monolayer using atomic force microscopy electrostatic nanolithography

We propose a simple approach to form 50-nm raised structures based on conformational changes of organomercaptan molecules assembled in monolayer on surface of gold. Manipulation of amphifunctional molecules may be performed using a strong electric field (10$^{8}$-10$^{10}$ Vm$^{-1})$ induced by an atomic force microscope (AFM) tip. Such a field leads to re-arrangement of alkylthiolates assembled on Au (111) resulting in nano-patterning of raised nanostructure (1.5-9 nm high, 20-50 nm wide) arrays on a second-time scale by manipulating the tip above the monolayer. It is suspected, that as a result of the oxidative cleavage initiated by a weak bias of the tip, the S-end of the chain carrying a sulfenium cation is attracted to the tip forming a bi-layer, and the higher-layer structures in monolayer. Stabilization of the multiple-layered structures is accomplished via mutual attraction and entanglement of the hydrocarbon chains.