Calculation of electrostatic solvation energies for polycyclic aromatic hydrocarbon mono-cations in acetonitrile

A modified generalized Born equation is incorporated with a semiempirical molecular orbital method to calculate electrostatic solvation energies for solute ions. A parameter corresponding to the atomic radius is introduced as a function of size of the solute ion and the position of the atom with respect to the solute surface. This method is applied to benzene and 17 polycyclic aromatic hydrocarbon mono-cations with various sizes and shapes in acetonitrile. The results are compared with experimental values obtained from the data of oxidation and ionization potentials. The present calculations based on the simple dielectric continuum model can predict the solvation energies with an average error of 0.07 eV.