On Some Extended Energy of Graphs and Their Applications

In this paper, we dealt with extended energy of graphs namely first and second Zagreb energy, Randić energy, reciprocal Randić energy, and the atom-bond connectivity energy. We studied their relationship with some thermodynamic properties of benzenoid hydrocarbons. We have seen that these indices are well correlated to the boiling point ( BP ), Kovats retention index ( RI ), entropy ( S ), enthalpy of formation ( ΔH f ), octanol-water partition coefficient ( log P ), and acentric factor ( ω ) of benzenoid hydrocarbons. Significantly, the correlation coefficients of Randić energy with the boiling point, enthalpy of formation, Kovats retention index, octanol-water partition coefficient, and acentric factor are greater than 0.97.