Extended First-Principles Molecular Dynamics Method From Cold Materials to Hot Dense Plasmas

TL;DR

This paper introduces an extended first-principles molecular dynamics method based on Kohn-Sham scheme that efficiently simulates hot dense plasmas, maintaining high accuracy while reducing computational costs for high-energy electrons.

Contribution

The authors develop an extension of the FPMD method that analytically treats high-energy electron wave functions as plane waves, enabling simulations of hot dense plasmas with high accuracy and lower computational costs.

Findings

Enables simulation of hot dense plasmas beyond previous temperature limits.

Maintains high accuracy of Kohn-Sham scheme in extended method.

Applicable to astrophysics, inertial confinement fusion, and laboratory astrophysics.

Abstract

An extended first-principles molecular dynamics (FPMD) method based on Kohn-Sham scheme is proposed to elevate the temperature limit of the FPMD method in the calculation of dense plasmas. The extended method treats the wave functions of high energy electrons as plane waves analytically, and thus expands the application of the FPMD method to the region of hot dense plasmas without suffering from the formidable computational costs. In addition, the extended method inherits the high accuracy of the Kohn-Sham scheme and keeps the information of elec- tronic structures. This gives an edge to the extended method in the calculation of the lowering of ionization potential, X-ray absorption/emission spectra, opacity, and high-Z dense plasmas, which are of particular interest to astrophysics, inertial confinement fusion engineering, and laboratory astrophysics.