Full rotational and vibrational energy levels of argon dimer by the solution of Lippmann-Schwinger integral equation in momentum

The Schrödinger equation is often solved in an effort to benchmark and design interatomic potentials. This work describes the numerical solution of the Schrödinger equation in its Lippmann-Schwinger form in momentum space by means of a direct technique to calculate argon dimer binding energies. Two models of argon-argon interaction developed by Patkowski et al. are employed. Our numerical analysis confirms not only the eight argon dimer vibrational levels of the ground state of argon dimer (i.e. for j=0) predicted by other groups but also provides a very precise means for determining the binding energy of the ninth state which its value is a matter of discussion. Our calculations have been also extended to states with higher rotational quantum numbers and we have calculated the energy of all 174 bound states for both potential models.