▎ 摘　　要

We have modeled the adsorption of various substituted derivatives of benzene on a graphene sheet, using a first-principles density functional theory-local density approximation method. The presence of functional groups can significantly alter the overall magnitude of pi-pi interactions between the adsorbed molecules and graphene by giving rise to strong medium-range interactions involving pi-orbitals of the substituents. When the substituents can simultaneously permit the formation of hydrogen bonds between adsorbed molecules, it is possible to evaluate the relative contributions of hydrogen bonding and T-based interactions to the overall adsorption. Adsorption of individual molecules and hydrogen-bonded aggregates reflects a hierarchical balance of the different interactions that determine the overall energy of adsorption.