On topological charge stabilization in heterocyclic compounds

Abstract

According to Gimarc's principle of topological chargestabilization, heteroatomic molecules are topologically stabilized when more electronegative atoms are placed in those positions where atom-atom connectivity and the electron-filling level provide the highest electron charge in the reference hydrocarbon frame. Recently, we showed that the relative atomic moments of energy (the frequencies of atomic self-returning walks) in such uniform molecular skeletons are equal to the respective squared principal eigenvector coefficients. We show here that for conjugated heteroryclic molecules these partial atomic charges follow closely the patterns mirrored by topological charge stabilization and, by producing a nonuniform charge distribution in alternant molecules, enable the broader application of this principle to such molecules.