Mobius aromaticity and delocalization

The evaluations done by scientists in 1993 demonstrated that pericyclic transition states proceeding with half-twist Mobius topology exhibit aromatic properties. The molecules sustaining Mobius electronic conjugation are important because of their chiral nature. In particular, electronic delocalization in such systems manifest itself not only in typically aromaticbond lengths but also in the degree of localization of the 180° phase shift in the orbital topology. Because of the chiral nonplanar symmetry of Mobius rings compared to the Huckel systems, reliable quantitative measures of their properties relative contributions of the π and σ electronic frameworks remain to be developed.