title: Calculation of intermolecular interactions in the benzene dimer using coupled-cluster and local electron correlation methods.
abstract: Potential energy curves for the parallel-displaced, T-shaped and sandwich structures of the benzene dimer are computed with density fitted local second-order Møller-Plesset perturbation theory (DF-LMP2) as well as with the spin-component scaled (SCS) variant of DF-LMP2. While DF-LMP2 strongly overestimates the dispersion interaction, in common with canonical MP2, the DF-SCS-LMP2 interaction energies are in excellent agreement with the best available literature values along the entire potential energy curves. The DF-SCS-LMP2 dissociation energies for the three structures are also compared with new complete basis set estimates of the interaction energies obtained from accurate coupled cluster (CCSD(T)) and DF-SCS-MP2 calculations. Since LMP2 is essentially free of basis set superposition errors, counterpoise corrections are not required. As a result, DF-SCS-LMP2 is computationally inexpensive and represents an attractive method for the study of larger pi-stacked systems such as truncated sections of DNA.
authors.affiliation: School of Chemistry, Cardiff University, Park Place, Cardiff, UK CF10 3AT.
authors.forename: J Grant
authors.initials: JG
authors.lastname: Hill
authors.forename: James A
authors.initials: JA
authors.lastname: Platts
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Werner