A superconfiguration code based on the local density approximation

The local density approximation (LDA) has been applied in a version of the SCO code based on the superconfiguration method. The self-consistent-held LDA equations for each superconfiguration are obtained by minimization of the free-energy functional with an appropriate number of constraints which guarantee the required populations of supershells. The one-electron states resulting from these SCF equations are then used in the Hartree-Fock formulas for transition energies, oscillator-strengths, UTA (or SOSA) widths and shifts and in the superconfiguration statistical sums. Applications of the present method to model the measured transmission 3d-4f spectra of low-temperature samarium plasma are discussed. It is found that the presented method gives results very close to those obtained using the finite temperature Hartree-Fock SCF atomic physics provided that: (a) the effective LDA potential contains the Kohn-Sham exchange supplemented by a correlation contribution and (b) the orbital relaxation effects are taken into account. Examples of calculated transmission spectra with and without inclusion of screening in the case of 2p-3d transitions in low-temperature iron plasma at small (0.004g/cm(3)) and solid densities are also shown. (C) 2000 Elsevier Science Ltd. All rights reserved.