The Impact of Basis Set Superposition Error on the Structure of π-π Dimers

The effect of basis set superposition error (BSSE) on the structure and energy of benzene, naphthalene, corannulene, and sumanene dimer has been analyzed. MP2 method was chosen and the effect is estimated using 6-31G, 6-31G(d), 6-311+G(d), cc-pVDZ, and cc-pVTZ basis sets. The model calculations on benzene dimer indicate that the impact of BSSE on the equilibrium geometry of p-stacked dimers appears to be quite significant. Calculations on larger molecular dimers such as the dimers of naphthalene, corannulene, and sumanene are also studied. The practical implication of the current observation on modeling the macromolecular structure is discussed. VC 2010 Wiley Periodicals, Inc. Int J Quantum Chem 111: 1893-1901, 2011