Noncovalent Interactions in Supramolecular Complexes: A Study on Corannulene and the Double Concave Buckycatcher

TL;DR

This study uses density functional theory to analyze noncovalent π-π interactions in corannulene complexes, validating computational methods and providing insights into the binding energies and electronic structures of supramolecular assemblies involving C60 and corannulene.

Contribution

It evaluates the performance of various density functionals for modeling noncovalent interactions in corannulene complexes, highlighting the accuracy of MPWB1K and M05-2X functionals.

Findings

MPWB1K and M05-2X functionals accurately reproduce benchmark energies.

Most popular density functionals fail to describe noncovalent interactions properly.

The binding energy of C60 with corannulene is approximately -20.67 kcal/mol.

Abstract

Stimulated by the recent observation of {\pi}-{\pi} interactions between C60 and corannulene subunits in a molecular tweezer arrangement (J. Am. Chem. Soc. 2007, 129, 3842), a density functional theory study was performed to analyze the electronic structure and properties of various noncovalent corannulene complexes. The theoretical approach is first applied to corannulene complexes with a series of benchmark molecules (CH4, NH3, and H2O) using several new-generation density functionals. The performance of nine density functionals, illustrated by computing binding energies of the corannulene complexes, demonstrates that Zhao and Truhlar's MPWB1K and M05-2X functionals provide energies similar to that obtained at the SCS-MP2 level. In contrast, most of the other popular density functionals fail to describe this noncovalent interaction or yield purely repulsive interactions. Further investigations with the M05-2X functional show that the binding energy of C60 with corannulene subunits in the relaxed molecular receptor clip geometry is -20.67 kcal/mol. The results of this calculation further support the experimental interpretation of pure {\pi}-{\pi} interactions between a convex fullerene and the concave surfaces of two corannulene subunits.