Investigation of fullerene motion on thermally activated gold substrates with different shapes

In the current study, the regime of motion of fullerene molecules on substrates with different shapes at a range of specific temperatures has been investigated. To do so, the potential energy of fullerene molecules was analyzed using the classical molecular dynamics method. C-20, C-36, C-50, C-60, C-72, C-76, C-80, and C-90 fullerene molecules were selected due to their spherical shapes with different sizes. In addition, to completely analyze the behavior of these molecules, different gold substrates, including flat, concave, the top side of the step (upward step), and the downside of the step (downward step) substrates, were considered. Specifying the regime of the motion at different temperatures is one of the main goals of this study. For this purpose, we have studied the translational and rotational motions of fullerene molecules independently. In the first step of the investigation, Lennard-Jones potential energy of fullerene molecules was calculated. Subsequently, the regime of motion of different fullerenes has been classified, based on their displacement and sliding velocity. Our findings indicated that C-60 is appropriate in less than 5% of the conditions. However, C-20, C-76 and C-80 molecules were found to be appropriate candidates in most cases in different conditions while they were incompetent only in seven situations. As far as a straight-line movement is considered, the concave geometry demonstrated a better performance compared to the other substrates. In addition, C-72 indicated less favorable performance concerning the range of movement and diffusion coefficients. All in all, our investigation helps to understand the performance of different fullerene molecules on gold substrates and find their probable application, especially as a wheel in nano-machine structures.

Automated summary

In this study, the motion regime of fullerene molecules on substrates with different shapes and temperatures was investigated using classical molecular dynamics method. It was found that different fullerene molecules exhibited different motion behaviors under specific conditions, with C-20, C-76, and C-80 molecules being the most suitable candidates in most cases. The concave geometry substrate demonstrated better performance in straight-line movement. However, C-72 molecule showed less favorable performance in terms of range of movement and diffusion coefficients.