Dynamic polarizabilities and van der Waals coefficients for the ground 2 (2)S and excited 2 (4)Po states of Li.

Abstract

The dynamic dipole polarizabilities at real and imaginary frequencies have been determined for the ground 2 $^{2}$S and excited 2 $^{4}$${\mathit{P}}^{\mathit{o}}$ states of Li using our time-dependent gauge-invariant method. Accurate ${\mathit{C}}_{6}$ dispersion energy coefficients for the Li(2 $^{2}$S)\char21{}${\mathrm{H}}_{2}$ and Li(2 $^{4}\mathrm{P}^{\mathrm{o}}$)\char21{}${\mathrm{H}}_{2}$ systems and their dependence on the intramolecular H-H distance are reported.