First-principles studies of liquid lithium under pressure

Area of Science:

• Condensed matter physics
• Materials science
• Computational chemistry

Background:

• Understanding the behavior of liquid metals under extreme conditions is crucial for various applications.
• Liquid lithium's unique properties make it a subject of interest for high-energy-density physics and fusion energy research.

Purpose of the Study:

• To investigate the effects of high pressure and temperature on the structural and electronic properties of liquid lithium.
• To explore potential structural transformations and their correlation with electronic structure evolution.

Main Methods:

• First-principles molecular dynamics simulations were employed.
• Simulations covered a pressure range up to 60 GPa and temperatures from 600 to 1000 K.

Main Results:

• Several structural transformations were observed in liquid lithium under high pressure.
• Liquid structure was found to be largely insensitive to temperature within the studied range.
• Radial distribution functions resembled those of solid phases, especially at lower pressures.
• Electronic structure evolution mirrored that of the corresponding solid phases.
• Instantaneous short-range order in liquid lithium can significantly deviate from the underlying solid phase.

Conclusions:

• High pressure induces significant structural changes in liquid lithium, with electronic properties closely following those of solid phases.
• Despite similarities in averaged structures, the dynamic nature of liquid lithium allows for instantaneous configurations distinct from solid structures.