A DEFICIENCY OF LOCAL-DENSITY FUNCTIONALS FOR THE CALCULATION OF SELF-CONSISTENT-FIELD ATOMIC DATA IN PLASMAS

In generating the atomic data base used in computing opacities of hot dense plasmas the local density functional approximation (LDA) is ofte n employed. One advantage of the LDA is that the configuration average energy of a large number of ionization states and excited configurati ons can be computed compactly using a multi-variate Taylor series expa nsion in occupation numbers. The pitfalls of employing a local density functional and its impact on the quality of the Taylor series approxi mation are discussed. The consequences of modeling opacities with a LD A are illustrated by comparisons with experiment. A method for obviati ng the problems inherent in the LDA is presented.