DYNAMIC POLARIZABILITY AND HYPERPOLARIZABILITY OF H- FOR FREQUENCIES BELOW AS WELL AS ABOVE THE IONIZATION THRESHOLD

Linear and nonlinear frequency-dependent polarizabilities are defined as time averages and computed efficiently from a Floquet theorem based many-electron, many-photon theory. The theory is formulated and implemented in terms of suitably chosen state-specific function spaces and yields the induced total energy shift to all orders for frequencies omega below, as well as above the ionization threshold. Application is made to H-, for which the reliable computation of even the static polarizability, α, is cumbersome. We have obtained α (201.8 au), α (ω), γ (0.76×108 au) and γ (ω), for ω =0.0-0.260 au. The forms of α (ω) and γ (ω) are the same as those for Li-. © 1990 IOP Publishing Ltd.