Influence of dissipation and effective interaction on the dense plasma dynamic structure factor

Area of Science:

• Condensed matter physics
• Computational materials science
• Physical chemistry

Background:

• Understanding ionic dynamics is crucial for materials properties.
• Molecular dynamics simulations are key tools for studying these dynamics.
• The interplay between dissipation and interionic forces needs clarification.

Purpose of the Study:

• To investigate the influence of dissipation models on ionic dynamic structure factors.
• To determine the sensitivity of dynamic structure factors to effective ionic interactions.
• To identify key parameters for constraining interionic potentials.

Main Methods:

• Utilized molecular dynamics simulations with two distinct dissipation models.
• Varied parameters of the effective ionic interaction, including pseudopotential and screening.
• Analyzed the dynamic structure factor, focusing on "diffusive" peaks.

Main Results:

• Dissipation models showed negligible impact on dynamic structure factor amplitudes.
• Diffusive peaks exhibited high sensitivity to the form of the ionic interaction.
• Pseudopotential details were identified as the primary driver of this sensitivity.

Conclusions:

• The effective ionic interaction, especially atomic physics aspects, dominates dynamic structure factor behavior.
• Measured zero-frequency dynamic structure factor S_{ii}(k,0) can serve as a constraint for interionic potentials.
• This approach can improve the computation of material physical properties.