Three-center Harary index and its applications

The Harary index H can be viewed as a molecular structure descriptor composed of increments representing interactions between pairs of atoms, such that their magnitude decreases with the increasing distance between the respective two atoms. A generalization of the Harary index, denoted by Hk, is achieved by employing the Steiner-type distance between k-tuples of atoms. We show that the linear combination H+x H3 is significantly better correlated with a variety of physico-chemical properties of alkanes than H itself.