Density-functional calculations of transport properties in the non-degenerate limit and the role of electron-electron scattering

TL;DR

This paper uses density functional theory to calculate hydrogen plasma conductivities and introduces an explicit electron-electron scattering correction to improve accuracy in the non-degenerate regime.

Contribution

It presents a novel correction to DFT calculations for plasma transport properties by incorporating electron-electron scattering effects based on plasma kinetic theories.

Findings

DFT underestimates thermal conductivity without e-e corrections.

Explicit e-e scattering correction aligns DFT results with kinetic theory.

Proper convergence in DFT calculations is crucial for accurate plasma transport predictions.

Abstract

We compute electrical and thermal conductivities of hydrogen plasmas in the non-degenerate regime using Kohn-Sham Density Functional Theory (DFT) and an application of the Kubo-Greenwood response formula, and demonstrate that for thermal conductivity, the mean-field treatment of the electron-electron (e-e) interaction therein is insufficient to reproduce the weak-coupling limit obtained by plasma kinetic theories. An explicit e-e scattering correction to the DFT is posited by appealing to Matthiessen's Rule and the results of our computations of conductivities with the quantum Lenard-Balescu (QLB) equation. Further motivation of our correction is provided by an argument arising from the Zubarev quantum kinetic theory approach. Significant emphasis is placed on our efforts to produce properly converged results for plasma transport using Kohn-Sham DFT, so that an accurate assessment of the importance and efficacy of our e-e scattering corrections to the thermal conductivity can be made.