CH/pi interaction in benzene and substituted derivatives with halomethane: a combined density functional and dispersion-corrected density functional study.

The present work intends to establish the efficiency of dispersion-corrected density functionals in explaining the potential energy curves of benzene-methane, benzene-fluoroform, and 1,3,5-trifluoro benzene-methane complexes. The interaction energies of all of the complexes under investigation have been evaluated using both van der Waals-corrected and normal gradient-corrected Perdew-Burke-Ernzerhof and Becke-Lee-Yang-Parr density functionals. Our analyses suggest that the potential energy curves for both benzene-methane and benzene-fluoroform complexes are in excellent agreement with highly accurate coupled cluster (CCSD(T)) results as well as high-level counterpoise-corrected MP2 results.