Molecular connectivity methods for the characterization of surface energetics of liquids and polymers

In the topological approach to structure–property relationships, the molecular structure is described in terms of appropriate weighted graphs to which suitable topological parameters, usually known as molecular connectivity indices, can be associated. Molecular connectivity indices are here applied to the prediction of surface free energy and Good–van Oss–Chaudhury acid–base components of organic compounds. To this aim, some quantitative structure–property relationships (QSPRs) are determined, involving both topological indices and group indicator variables of the customary functional group theory. The semiempirical models obtained to appear satisfactory and show significant advantages with respect to the models based on the purely functional group approach