Multicenter bond indices as a new means for the quantitative characterization of homoaromaticity

This study reports the use of multicenter bond indices as a new tool for the quantitative characterization of homoaromaticity. The approach was applied to the series bicyclic systems whose homoaromaticity was recently discussed in terms of traditional aromaticity index, namely, NICS. In this study we found that the multicenter bond indices are indeed able to quantify the degree of homoaromaticity of the studied systems as reflected in the classification of these molecules into classes of homoaromatic, non-homoaromatic, and anti-homoaromatic systems suggested on the basis of NICS values.