Gas-phase spectroscopic detection of tiny carbon clusters is a recent success story in the area of carbon cluster research. However, experimental production and isolation of these clusters are extremely difficult because of their high reactivity. One possibility to isolate the generated clusters would be to deposit them on graphene and to desorb them for subsequent use. One of the pertinent questions toward realizing this would be the energetics of the adsorption process. Therefore, in this work, the energetics for the adsorption of the monocyclic carbon rings (Cn with n = 10, 12, 14, 16, 18, 20, and 22) on a graphene sheet are investigated using the analytical approaches, developed earlier by Hill and co-workers. The adsorption process here is driven by the noncovalent interactions between the carbon rings and the graphene sheet. The analyses of the interaction energies as a function of both the vertical distance Z and the rotational angle ϕ are performed in order to determine the preferred orientations, equilibrium positions, and binding energies for the adsorption ofvarious carbon rings on graphene. We find that the preferred orientationof the rings with respect to the graphene sheet is the parallel orientation.The results from continuum, discrete–continuum, and discretemodels are in good agreement. Further, computations using densityfunctional theory and quantum mechanics/molecular mechanics approachesare performed, and comparisons of the computed energetics with thedata from the models are reported. Finally, we highlight the scopeand the limitations of the analytical models.
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