Electronic structure and energetics of praseodymium and $\alpha$-plutonium under pressure

TL;DR

This paper introduces a new computational approach combining Gutzwiller approximation with LDA to study complex actinide and lanthanide systems, successfully reproducing experimental pressure-induced phase transitions and electronic properties.

Contribution

A novel implementation of the Gutzwiller approximation interfaced with LDA for accurate modeling of 4f and 5f electron systems under pressure.

Findings

Accurately reproduces pressure-induced phase transitions in praseodymium and alpha-plutonium.

Highlights the importance of f-electron delocalization and correlations in phase stability.

Provides insights into the electronic structure and thermodynamics of actinide and lanthanide metals.

Abstract

We develop a new implementation of the Gutzwiller approximation (GA) and interface it with the local density approximation (LDA). This formulation enables us to study complex $4f$ and $5f$ systems. We perform calculations of praseodymium and $\alpha$-plutonium under pressure, which compare very well with the experiments. Our study of praseodymium indicates that both structure change and $f$-delocalization are important to obtain the correct phase diagram and, in particular, the pressure-induced volume-collapse transition. Our calculations of $\alpha$-plutonium indicate that, even though the $f$ electrons are delocalized in this phase, the electron-correlations affect substantially its electronic structure and thermodynamical properties.