A theoretical investigation of the interaction between substituted pyridines and CS2. Versatility of the CS2 molecule

Abstract

Abstract The interaction between carbon disulfide and para-substituted pyridines (X = NH2, CH3, H, F, CN, NO2) are investigated by theoretical methods. Four different stable structures are detected for the complexes at the MP2 = full/aug-cc-pVDZ level of theory. The A structures having bonding energies between −9.34 and −11.57 kJ/mol are characterized by N⋯S chalcogen bonds. In the B structures, the interaction energies range between −8.86 and −9.37 kJ/mol and the complexes are bonded by N⋯C tetrel bonds. In the C structures, characterized by interaction energies between −12.20 and −15.03 kJ/mol, the molecules are bonded by S…π interactions. The D complexes involve, in addition to N⋯S chalcogen bonds, a direct participation of the substituents in the bonding process. They have the largest binding energies, between −18.06 and −24.22 kJ/mol. The nature and properties of the four complexes are analyzed by natural bond orbitals (NBO) calculations, atoms in molecules (AIM) analysis and energy decomposition (SAPT) calculations. The role of the basicity of the pyridines and the influence of the electrostatic potential of the pyridines on the charge transfer is outlined.