Abstract.  During the last decade the development of powerful laser facilities opened the way to create and study warm dense matter (WDM) in the laboratory. This state, characterized by roughly solid densities and a few electronvolts of temperature, occurs under large pressure like in the interior of giant gas planets. It is a highly correlated state that is governed by electron degeneracy and, for most elements, bound states. WDM also occurs as a transient state during the capsule implosion in inertial confinement fusion experiments. In this context, mixing of fuel and ablator material is of high interest and plasmas with multiple species need to be studied under shock-compressed conditions to optimize the performance of ICF targets.

To diagnose WDM, energetic particles and x-rays are employed as WDM is opaque in the visible due to the high electron densities. However, these methods require a precise and computational eective theoretical description of the material under investigation since the plasma parameters are mostly deduced as fit parameters that match the measurements. In this contribution, we will present a consistent theory for the structure in WDM combining strongly coupled ions and degenerate electrons. The structural information are obtained by either full quantum simulations (like DFT-MD) or a quasi-classical approach that uses the hypernetted chain (HNC) equations. The first method is an ab initio approach with high accuracy, but it is limited by the high numerical eort. Fitted potentials are thus applied within the HNC method to improve the applicability and keep the signicant material properties. Moreover, we have generalized the theoretical basis to also allow for the description of systems with multiple ion species. We finally apply this method for several mixtures in the WDM regime and highlight the difference to a treatment that uses average ionization stages in a single-ion approach.