A DFT-D evaluation of the complexation of a molecular tweezer with small aromatic molecules

We use dispersion-corrected density functional theory approaches (DFT-D) to investigate the structure and properties of complexes constituted of an aromatic tweezer and aromatic molecules. It turns out that a B97-D/6-31G(d) geometry optimisation yields reasonably accurate structural parameters, whereas larger basis sets and the latest DFT-D models are required to adequately mimic the complexation energies measured through NMR experiments. This contribution highlights that ab initio schemes may be pertinent to investigate the binding energies of large association complexes, even when the studied interaction is relatively weak and shows a non specific character, with a significant dispersion contribution. (C) 2011 Elsevier B. V. All rights reserved.