On 𝜋–electron excess of rings of benzenoid hydrocarbons

Abstract

In a previous paper [Gutman I, Indian J Chem 43A (2004) 1615], the concept of pi-electron excess of rings of benzenoid hydrocarbons has been introduced, aimed at amending the electron contents of rings computed on the basis of Pauling bond orders. We now show how a -electron-content-like quantity can be computed from the Hosoya bond orders and establish its close relation with the π-electron excess.