Analysis in silico of chemical reactivity employing the local hyper-softness in some classic aromatic compounds, boron aromatic clusters and all-metal aromatic clusters

In the current work, the authors analyzed and compared the chemical behavior of some (anti)aromatic compounds. The species selected are benzene and cyclobutadiene as the aromatic and antiaromatic classical examples, respectively. Next, the anion (Formula presented.), which is the first all-metal molecule catalogued as aromatic and its non-metallic isoelectronic analog, (Formula presented.) were also analyzed. The antiaromatic clusters (Formula presented.) and (Formula presented.) were studied in form of lithium salts. And the end, the non-planar (Formula presented.) boron cluster and its isoelectronic analogs ((Formula presented.) and (Formula presented.)) were considered for being analyzed under the same criterium. The analysis was realized employing the following descriptors: molecular electrostatic potential and local hyper-softness to get insights concerning local reactivity when facing reagents leading to ionic or covalent interactions. The results show that all the molecules analyzed presented some specific variations in their respective local reactivity despite being labeled as aromatic compounds. This analysis provides a notion that the local reactivity is more based on the nature of the atoms and the molecular geometry than the aromatic character by itself.