Reduced ionic diffusion by the dynamic electron–ion collisions in warm dense hydrogen

Abstract

The dynamic electron–ion collisions play an important role in determining the static and transport properties of warm dense matter (WDM). The electron force field (EFF) method is applied to study the ionic transport properties of warm dense hydrogen. Compared with the results from quantum molecular dynamics and orbital-free molecular dynamics, the ionic diffusions are largely reduced by involving the dynamic collisions of electrons and ions. This physics is verified by the quantum Langevin molecular dynamics (QLMD) simulations, which includes electron–ion collision-induced friction (EI-CIF) into the dynamic equation of ions. Based on these new results, we proposed a model including the correction of collision-induced friction of the ionic diffusion. The CIF model has been verified to be valid in a wide range of densities and temperatures. We also compare the results with the Yukawa one-component plasma (YOCP) model and Effective OCP (EOCP) model. We proposed to calculate the self-diffusion coefficients using the EOCP model modified by the CIF model to introduce the dynamic electron–ion collision effect.