Maximum topological distances based indices as molecular descriptors for QSPR.: V-modeling the free energy of hydrocarbons

The Gibbs free energy for a set of 60 hydrocarbons is calculated on the basis of topological indices defined from the distance and detour matrices within the realm of the QSPR theory. Linear and non-linear polynomials fittings are performed and the results demonstrate the need to resort to higher-order regression functions in order to obtain better agreements between theoretical results and experimental thermodynamics data. Topological indices calculated from detour matrix yield rather satisfactory predictions of Gibbs free energy for hydrocarbons.