On the incremental evaluation of BSSE-free interaction energies

A recently proposed approximate procedure to calculate directly the BSSE-free binding energy of a H2S-benzene complex within the incremental scheme for the evaluation of correlation contributions is tested for the dimers of helium, methane, water and hydrogen sulfide at the coupled cluster level. The counterpoise corrected binding energy as well as the basis set extrapolated binding energy are evaluated in conventional manner and compared to results obtained with the recently proposed scheme. Furthermore the basis set dependence of the results is monitored. It is demonstrated that the new proposal is not generally applicable and in particular that larger basis sets do not improve the accuracy of the results.