Non-relativistic ab initio calculations for $2^2S$, $2^2P$ and $3^2D$ lithium isotopes: Applications to polarizabilities and dispersion interactions

Abstract

The electric dipole polarizabilities and hyperpolarizabilities for the lithium isotopes 6 Li and 7 Li in the ground state 2 2 S and the excited states 2 2 P and 3 2 D, as well as the leading resonance and dispersion long-range coefficients for the Li(2 2 S)-Li(2 2 S) and Li(2 2 S)-Li(2 2 P ) systems, are calculated nonrelativistically using variational wave functions in Hylleraas basis sets. Comparisons are made with published results, where available. We find that the value of the second hyperpolarizability of the 2 2 S state is sensitive to the isotopic mass due to a near cancellation between two terms. For the 3 2 D state polarizability tensor the calculated components disagree with those measured in the sole experiment and with those calculated semi-empirically.