Quchan Branch, Islamic Azad University, Quchan , I.R. IRAN
In this study, the effects of non-covalent interactions are considered where the hydrogen cyanide act as a proton donor and different π-systems such as para-substituted (H, F, Cl, OH, SH, CH3, and NH2) benzene derivatives act as a proton acceptor. The complexes are optimized by the B3LYP method using 6-311++G** basis set. The intermolecular interaction energyis determined at the same level with BSSE corrections. In addition to geometrical parameters and binding energies, topological properties of electron charge density are calculated by atoms in molecules (QTAIM) method. Furthermore, the Natural Bond Orbital (NBO) analysis is applied to get a more precise insight into the nature of these interactions. Several correlations between topological, geometrical and energetic parameters are found. Finally, the effects of interactions on NMR data have been used to more investigation of the studied compounds.