Topological characteristics of the Ring Critical Points and the aromaticity of groups IIIA to VIA hetero-benzenes

The relative aromaticity of the hetero-atom containing benzenes (groups IIIA to VIA) was investigated using the magnetic and energetic criteria of aromaticity. Topological properties of electron density at the Ring Critical Points (RCP) were also studied and the advantages of using these points for evaluation of the NICS index of aromaticity were shown in comparison with the classical criteria. Although, in each group of Periodic Table RCP characteristics are almost in accordance with classical aromaticity criteria, i.e. magnetic and energetic indices of the aromaticity, in general, the relationship between the topological properties of the RCP and the magnetic and energetic indices fails.