# Variational average-atom model of electron-ion plasma with correlations and quantum bound electrons

## TL;DR

This paper introduces a variational average-atom model for electron-ion plasma that combines quantum treatment of bound electrons with correlation effects, improving accuracy in plasma modeling.

## Contribution

It presents a novel variational model (VAAQBEC) that self-consistently includes correlations and quantum bound electrons, bridging gaps in existing plasma models.

## Key findings

- Accurately models ion shell structure and correlations in plasma.
- Provides Debye-Hückel corrections for orbital energies.
- Shows good agreement with established models on silicon and iron cases.

## Abstract

In the present paper, we propose a variational average-atom model of electron-ion plasma performing a quantum treatment of bound electrons and accounting for correlations (VAAQBEC). This model addresses the correlation functions in a weakly-coupled plasma, while also accounting self-consistently for the ion average shell structure. This is done at the price of treating the free electrons classically, whereas bound electrons are treated quantum-mechanically. When ions are approximated by point-like particles, the present approach yields the usual Debye-H\"{u}ckel corrections to the orbital energies and chemical potential. If one disregards the interactions of continuum electrons, the present approach yields ion-ion correlation corrections through a self-consistent one-component-classical-plasma contribution. Comparisons are presented with the broadly-used continuum-lowering approach of Stewart and Pyatt and with the dense-plasma average-atom models INFERNO and VAAQP, on warm silicon and hot iron cases.