Multidimensionality of delocalization indices and nucleus independent chemical shifts in polycyclic aromatic hydrocarbons |
| |
Authors: | Fias Stijn Van Damme Sofie Bultinck Patrick |
| |
Institution: | Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 (S3), 9000 Gent, Belgium. |
| |
Abstract: | The aromaticity and local-aromaticity of a large set of polycyclic aromatic hydrocarbons (PAHs) is studied using multicenter delocalization indices from generalized population analysis and the popular nucleus independent chemical shift (NICS) index. A method for the fast computation of the NICS values is introduced, using the so-called pseudo-pi-method. A detailed examination is made of the multidimensional nature of aromaticity. The lack of a good correlation between the NICS and the multicenter delocalization indices is reported and the grounds discussed. It is shown through a thorough statistical analysis that the NICS values arise not only from local aromaticity of the benzenoid rings, but also from other circuits. It is shown that the NICS indices do not reveal the individual aromatic nature of a specific ring, contrary to the delocalization indices. |
| |
Keywords: | aromaticity local-aromaticity generalized population analysis NICS chemical bond |
本文献已被 PubMed 等数据库收录! |
|