Multi-Center Electronic Structure Calculations For Plasma Equation of State

Brian Wilson
Lawrence Livermore National Laboratory

The generation of plasma equation of state data over wide ranges of temperature, density and material composition is a computationally intensive task. For this reason there is a traditional reliance on single ‘average-ion-in-jellium’ models and an assumption of ideal gas mixing of components. However in the warm dense mater regime the electronic wave-function behavior strongly reflects the influence of multiple ion centers. The electronic structure about any nuclear site is then no longer well approximated by a neutral ion sphere in an effective spherically symmetric field. We report on an alternative approach utilizing solid-state multi-center scattering techniques, generalized to finite temperatures, for computing electronic structure. The plasma is modeled as ensembles of quasi crystals, each lattice-cell consisting of many amorphously positioned nuclei. This approach has the advantage of handling mixtures at a fundamental level without the imposition of ad hoc continuum lowering models, and incorporates bonding and charge exchange, as well as multi-center effects in the calculation of the continuum density of states.

Presentation (PDF File)

Back to Workshop IV: Computational Challenges in Warm Dense Matter