Dynamic Multipole Polarizabilities of the Rare-Gas Atoms Ne, Ar, and Kr and Long-Range Interaction Coefficients of the Rare-Gas Atoms and with H2

Dynamic polarizabilities and excitation energies are obtained from multireference configuration interaction wave functions. The multiconfigurational reference function is designed to represent the ground state as well as the perturbed states and the first excited state on equal footing; i.e., orbital optimization is performed in a perturbed multiconfigurational self-consistent field procedure. Furthermore, perturbed and excited multireference configuration interaction wave functions are obtained simultaneously for several frequencies of the perturbing field. Reduced three-term spectra are derived which reproduce exactly the calculated polarizabilities at the selected frequencies and very well interpolate the dynamic polarizabilities up to the first pole. These reduced spectra also serve to calculate long-range interaction coefficients. The results for both the dynamic polarizabilities and the interaction coefficients are found to be in excellent agreement with experimental values where such data exists and also with most accurate theoretical results.