Coupled cluster calculations of interaction energies in benzene–fluorobenzene van der Waals complexes

Benzene–fluorobenzene complexes are used as model systems to simulate the interactions of the SBB-HCAII protein–ligand complex. Using the second-order Møller–Plesset [MP2] and the coupled cluster singles and doubles including connected triple excitations models recently implemented with Cholesky decompositions we evaluate accurate interaction energies for several benzene–fluorobenzene van der Waals complexes. We consider edge-to-face interactions and compare the results to those from a recent MP2 study and to experimental findings. In contrast to experimental trends, we find that the interaction tends to decrease with increasing fluorination and conclude that benzene–fluorobenzene complexes are too simple to simulate the full SBB-HCAII protein–ligand system.