Executive Summary : | Molecular machines, such as molecular wheels, vehicles, pumps, and scissors, have been identified in biological systems where a single protein performs specific tasks on stimulation with perfect accuracy. Scientists have successfully synthesized artificial molecular machines for specific movements and tasks, such as Molecular wheels, Vehicles, pumps, and scissors. To develop more complex molecular machines, it is necessary to integrate several molecules to transfer mechanical energy from one molecule to another, such as in macroscopic gears. These molecular gears must be able to perform unidirectional rotation under external stimuli like photons, heat, or tunneling current. The gearing properties of molecules on the surface depend on the ability of a molecule to maintain an appropriate and fixed distance between each other. However, the gear action from such molecules has limited success due to the flexibility of the molecule and strong Vander Waal interactions among gear molecules. Theoretically, the gear action with a train of gears can be performed by putting some restriction on the translational movement of molecules on the surface, but this is a hypothetical model and impractical for real-life implementation on metallic or non-metallic surfaces. One promising candidate for this purpose could be covalent organic frameworks (COFs), two- or three-dimensional crystalline polymers formed through the covalent bond between carbon, nitrogen, and oxygen units with strong ?-? interlayer interactions. COFs can be prepared using molecular units, providing desired properties and specific uses. This project aims to investigate novel molecular gears designed using COFs that can transfer rotational energies from one molecule to another molecule adsorbed on the solid surface through quantum molecular dynamics tools. |