Light-induced on-surface synthesis of molecular chains on metallic and insulating surfaces


So far, on-surface chemistry has relied almost exclusively on Ullman coupling. This mechanism employs metallic surface as catalysts and heat to form covalent organic frameworks. Despite remarkable success, there is quest for new reaction mechanisms that avoid high temperature and metal catalysts. For example, high temperatures can lead to molecular desorption or decomposition. On the other hand, the electrons of a metallic surface can couple with molecular orbitals, hampering characterization of their electronic properties. One possibility to circumvent this problem is to synthetize molecular nanostructures by light and free of metal agents. We want to study the photochemically (i.e. non-thermal) driven on-surface synthesis of polymers on thin insulating films. We will use high-resolution scanning probe microscopy to characterize the chemical structures of intermediate and final products of the reaction. This allows us, with help of theoretical simulations, to understand the reaction pathways