Opacity of hot and dense plasmas of a mixture using an average-atom approach

An average-atom model is proposed to calculate the opacities of hot and dense plasmas of a mixture. A self-consistent scheme is used to reach the requirements of the same temperature and chemical potential for all kinds of atoms in the mixtures, the same electron density at the boundaries between the atoms, and the electrical neutrality within each atomic sphere. The orbital energies and wavefunctions for the bound electrons are calculated with the Dirac-Slater equations. The occupation numbers at each orbital of each kind of atom are determined by the Fermi-Dirac distribution with the same chemical potential for all kinds of atoms. As an example, the opacity of the mixture of Au and Cd is calculated at a few temperatures and densities