INTERACTIONS
The p–p interactions are fundamental to many supramolecular organization and
recognition processes.71 There are many theoretical and experimental studies that
clearly show the importance of p–p interactions.72 Perhaps the simplest prototype
of aromatic p–p interactions is the benzene dimer.73 Within dimeric aryl systems
such as this, possible p–p interactions are the sandwich and T-shaped interactions
shown. It has been shown that all substituted sandwich dimers bind more strongly
than benzene dimer, whereas the T-shaped configurations bind more or less favorably
depending on the substituent.74 Electrostatic, dispersion, induction, and exchangerepulsion
contributions are all significant to the overall binding energies.74