A simple density-functional calculation of frequency-dependent multipole polarizabilities of noble gas atoms

Abstract

Using a new density-functional equation proposed by us recently, frequency-dependent 2^L-pole (L = 1, 2, 3, 4) polarizabilities of He, Ne, Ar, Kr and Xe in their ground states have been calculated by numerically solving for each frequency only two, instead of 2N (N = number of electrons), perturbative equations. Results obtained with our calculated densities are satisfactory for Kr and Xe, but are considerably overestimated for He, Ne and Ar due to the adoption of local density approximation for the exchange-correlation potential and to the errors in the unperturbed densities for r<1 a.u. However, 2^L-pole polarizabilities and dipole shielding factors for all the five atoms, calculated by using Hartree-Fock densities as unperturbed functions, show uniformly good agreement with available experimental and other calculated values. Therefore, for these quantities the present rather simple approach has considerable promise, further justifying the search for a density-based alternative quantum mechanics of many-electron systems.