Transformation of Self-Assembled Structure by the Addition of Active Reactant

We have designed and synthesized one molecular building block, an aromatic trialdehyde derivative with three aldehyde groups, to form a potentially active structure. The scanning tunneling microscopy (STM) images show that the trialdehyde derivative forms lamellar structures. By the addition of active reactant, 5-aminoisophthalic acid, it is found that the structure of the adlayer can be transformed from lamellar to hexagonal structure as was expected. The structural formation of molecular networks is attributed to the condensation reaction between aldehyde and amine. Density functional theory (DFT) calculations reveal the observation of structural transformation at the solid/liquid interface due to the more stable adsorption of the triimine product than that of the trialdehyde derivative.