Relative Contribution of Combined Kinetic and Exchange Energy Terms vs the Electronic Component of Molecular Electrostatic Potential in Hardness Potential Derivatives

The relative contribution of the sum of kinetic [(10/9)C-F rho((r) over bar)(2/3)] and exchange energy [(4/9)C-X rho((r) over bar)(1/3)] terms to that of the electronic part of the molecular electrostatic potential [V-el((r) over bar)] in the variants of hardness potential is investigated to assess the proposed definition of Delta(+)h(k) = -[V-el(N+1)(k) - V-el(N)(k)] and Delta(-)h(k) = -[V-el(N)(k) - V-el(N-1)(k)] (Saha; et al. J. Comput. Chem. 2013, 34, 662). Some substituted benzenes and polycyclic aromatic hydrocarbons (PAHs) (undergoing electrophilic aromatic substitution), carboxylic acids, and their derivatives are chosen to carry out the theoretical investigation as stated above. Intra- and intermolecular reactivity trends generated by Delta(+)h(k) and Delta(-)h(k) are found to be satisfactory and are correlated reasonably well with experimental results.