A functional to determine imaginary frequency multipole polarizabilities which lead to long-range dispersion constants

Abstract
The functional based on the hydrodynamic model ansatz for the total time-dependent wave function is used to determine imaginary frequency multipole polarizabilities for the ground states of H, He+, He and Li+. The long-range dispersion terms for pairs of these atoms are also given. The functional is shown to give a convenient alternative to the determination of α 2l ().