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Sandwich and T‐shaped configurations of substituted benzene dimers were studied by second‐order perturbation theory to determine how substituents tune π–π interactions. Remarkably, multiple substituents have an additive effect on the binding energy of sandwich dimers, except in some cases when substituents are aligned on top of each other. The energetics of substituted T‐shaped configurations are more complex, but nevertheless a simple model that accounts for electrostatic and dispersion interactions (and direct contacts between substituents on one ring and hydrogen atoms on the other), provides a good match to the quantum mechanical results. These results provide insight into the manner by which substituents csan be utilized in supramolecular design.