Perturbation calculations of the interaction energy between closed-shell Hartree-Fock atoms

Interaction energy between two neon atoms described by the Hartree-Fock wavefunctions has been calculated through the second order of the symmetry-adapted perturbation theory. Particular contributions, the first order energy, dispersion, induction, exchange-dispersion and exchange-induction energies, are analysed and the basis set effects are discussed. The calculated values of the interaction energies are close to the experimental energies.