Simulations of the Tip of a Single-Walled Carbon Nanotube Interacting with a Graphite Substrate Through van der Waals Forces

Potential applications for carbon nanotubes (CNTs) include their use in atomic force microscopy and in adhesives. However, further analysis is needed. We present the modeling and analysis of the tip of a single-walled CNT interacting with a graphite substrate. The tip of the CNT is modeled as a chain of rigid links connected by torsional springs. The tip interacts with the substrate through van der Waals forces. We study a static version of the problem in which the substrate is fixed at various distances below the top link. Steady-state solutions are found using minimization techniques. Much work was done on verifying the accuracy of the model and testing its limits. Our results provide additional understanding of how the tip of a single-walled CNT bends and of the interaction forces experienced by the tip as a function of its configuration and its distance from the substrate.