Comment on “A computational study of the structures of van der Waals and hydrogen-bonded complexes of ethene and ethyne”

The weakly bonded complexes C2H2-Cl2 and C2H2-HCl are studied using extended basis sets at the HF, BLYP, B3LYP, and MP2 levels of theory. The interaction energies obtained from BLYP and B3LYP for the C2H2-Cl2 and the C2H2-HCl are smaller than those from MP2 in our calculations. It is necessary that the extended basis set should be used in order to compare between the binding energies from various levels of theory for the investigation of weakly bonded complexes.