Alkali-Metal-Induced Modulation of Intermolecular Interactions and Structural Transformations of Metal–Organic Nanostructures

Metal–organic nanostructures are of fundamental interest in the field of surface science due to their high structural and property tunability. Alkali-based metal–organic nanostructures, characterized by greater flexibility in geometries, have been constructed on surfaces and tuned by different types and dosage of alkali metals, as well as coverage of organic molecules, which directly determine the metal–organic and molecule–molecule interactions, respectively. However, the diversity of intermolecular interactions induced by the introduction of alkali metals in the construction of metal–organic nanostructures has received less attention, which would provide fundamental insights into the subtle interplay of metal–organic interactions and molecule–molecule interactions. In this study, on the basis of scanning tunneling microscopy imaging and density functional theory calculations, structural transformations and diversity of intermolecular interactions induced by alkali metals (Na, K, and Cs) have been visualized in a stepwise manner on Au(111). With the increasing dosage of alkali atoms, the evolving synergy of metal–organic interactions and molecule–molecule interactions has also been revealed, which would inspire the precise construction and regulation of metal–organic nanostructures.