Constitutional dynamic chemistry (CDC), including both dynamic covalent chemistry and dynamic noncovalent chemistry, relies on reversible formation and breakage of bonds to achieve continuous changes in constitution by reorganization of components. In this regard, CDC is considered to be an efficient and appealing strategy for selective fabrication of surface nanostructures by virtue of dynamic diversity. Although constitutional dynamics of monolayered structures has been recently demonstrated at liquid/solid interfaces, most of molecular reorganization/reaction processes were thought to be irreversible under ultrahigh vacuum (UHV) conditions where CDC is therefore a challenge to be achieved. Here, we have successfully constructed a system that presents constitutional dynamics on a solid surface based on dynamic coordination chemistry, in which selective formation of metal–organic motifs is achieved under UHV conditions. The key to making this reversible switching successful is the molecule–substrate interaction as revealed by DFT calculations.

Constitutional dynamic chemistry (CDC), including both dynamic covalent chemistry and dynamic noncovalent chemistry, relies on reversible formation and breakage of bonds to achieve continuous changes in constitution by reorganization of components. In this regard, CDC is considered to be an efficient and appealing strategy for selective fabrication of surface nanostructures by virtue of dynamic diversity. Although constitutional dynamics of monolayered structures has been recently demonstrated at liquid/solid interfaces, most of molecular reorganization/reaction processes were thought to be irreversible under ultrahigh vacuum (UHV) conditions where CDC is therefore a challenge to be achieved. Here, we have successfully constructed a system that presents constitutional dynamics on a solid surface based on dynamic coordination chemistry, in which selective formation of metal–organic motifs is achieved under UHV conditions. The key to making this reversible switching successful is the molecule–substrate interaction as revealed by DFT calculations.

Through the interplay of high-resolution scanning tunneling microscopy imaging and density functional theory calculations, the stepwise dehydrogenative homocoupling of alkyl chains on Cu(110) is demonstrated, proceeding from the intact chain, via the dehydrogenative intermediates, to the formation of the divers final coupling products.

Template cations have been extensively employed in the formation, stabilization and regulation of structural polymorphism of G-quadruplex structures in vitro. However, the direct addition of salts onto solid surfaces, especially under ultra-high-vacuum (UHV) conditions, to explore the feasibility and universality of the formation of G-quartet complexes in a solventless environment has not been reported. By combining UHV-STM imaging and DFT calculations, we have shown that three different G-quartet-M (M: Na/K/Ca) complexes can be obtained on Au(111) using alkali and alkaline earth salts as reactants. We have also identified the driving forces (intra-quartet hydrogen bonding and electrostatic ionic bonding) for the formation of these complexes and quantified the interactions involved. Our results demonstrate a novel route to fabricate G-quartet-related complexes on solid surfaces, providing an alternative feasible way to bring metal elements to surfaces for constructing metal–organic systems.

Homocouplings of hydrocarbon groups including alkynyl (sp¹), alkyl (sp³), and aryl (sp²) have recently been investigated on surfaces with the interest of fabricating novel carbon nanostructures/nanomaterials and getting fundamental understanding. Investigated herein is the on-surface homocoupling of an alkenyl group which is the last elementary unit of hydrocarbons. Through real-space direct visualization (scanning tunneling microscopy imaging) and density functional theory calculations, the two terminal alkenyl groups were found to couple into a diene moiety on copper surfaces, and is contrary to the common dimerization products of alkenes in solution. Furthermore, detailed DFT-based transition-state searches were performed to unravel this new reaction pathway.

Scanning tunneling microscopy (STM) manipulation techniques have proven to be a powerful method for advanced nanofabrication of artificial molecular architectures on surfaces. With increasing complexity of the studied systems, STM manipulations are then extended to more complicated structural motifs. Previously, the dissociation and construction of various motifs have been achieved, but only in a single direction. In this report, the controllable scission and seamless stitching of metal–organic clusters have been successfully achieved through STM manipulations. The system presented here includes two sorts of hierarchical interactions where coordination bonds hold the metal–organic elementary motifs while hydrogen bonds among elementary motifs are directly involved in bond breakage and re-formation. The key to making this reversible switching successful is the hydrogen bonding, which is comparatively facile to be broken for controllable scission, and, on the other hand, the directional characteristic of hydrogen bonding makes precise stitching feasible.

Scanning tunneling microscopy (STM) manipulation techniques have proven to be a powerful method for advanced nanofabrication of artificial molecular architectures on surfaces. With increasing complexity of the studied systems, STM manipulations are then extended to more complicated structural motifs. Previously, the dissociation and construction of various motifs have been achieved, but only in a single direction. In this report, the controllable scission and seamless stitching of metal–organic clusters have been successfully achieved through STM manipulations. The system presented here includes two sorts of hierarchical interactions where coordination bonds hold the metal–organic elementary motifs while hydrogen bonds among elementary motifs are directly involved in bond breakage and re-formation. The key to making this reversible switching successful is the hydrogen bonding, which is comparatively facile to be broken for controllable scission, and, on the other hand, the directional characteristic of hydrogen bonding makes precise stitching feasible.

Homocouplings of hydrocarbon groups including alkynyl (sp¹), alkyl (sp³), and aryl (sp²) have recently been investigated on surfaces with the interest of fabricating novel carbon nanostructures/nanomaterials and getting fundamental understanding. Investigated herein is the on-surface homocoupling of an alkenyl group which is the last elementary unit of hydrocarbons. Through real-space direct visualization (scanning tunneling microscopy imaging) and density functional theory calculations, the two terminal alkenyl groups were found to couple into a diene moiety on copper surfaces, and is contrary to the common dimerization products of alkenes in solution. Furthermore, detailed DFT-based transition-state searches were performed to unravel this new reaction pathway.

Scanning tunneling microscopy (STM) manipulation has received wide attention in the surface science community since the pioneering work of Eigler to construct surface nanostructures in an atom by atom fashion. Lots of scientists have been inspired and devoted to study the surface issues with the help of STM manipulations and great achievements have been obtained. In this Minireview, we mainly describe the recent progress in applying STM manipulations to regulate the inter-adsorbate and adsorbate–substrate interactions on solid surfaces. It was shown that this technique could not only differentiate intermolecular interactions but also construct molecular nanostructures by regulating different kinds of inter-adsorbate interactions or adsorbate–substrate interactions.

Catalytic reactions occurring on oxide-supported Cu and Cu-supported oxide catalysts are of fundamental interest in both industrial and scientific fields. Though the interface between Cu and oxide species has been regarded as the reaction site, the exact role of the interface in the catalytic reactions is not fully understood yet. In this work, by using a model system including CuO chains supported on Cu(1 1 0) and an organic molecule with alkynyl and aldehyde groups, we attempted to obtain a fundamental understanding of the role of the interface in the catalytic reactions. A combination of high-resolution scanning tunneling microscopy imaging and density functional theory calculations provided direct evidence at the atomic scale that the interface between the CuO chains and the Cu(1 1 0) surface is the most favorable site for the adsorption and activation of organic molecules, and the oxygen of CuO has an activity to oxidize both the alkynyl and aldehyde groups of the molecules adsorbed at the interface.