Electronic structure and magnetic state of transuranium metals under pressure

TL;DR

This study investigates the electronic structure and magnetic states of transuranium metals Np, Pu, Am, and Cm under pressure using advanced computational methods, revealing their coupling schemes and electron delocalization behaviors.

Contribution

It applies the LDA+U+SO method to analyze pressure effects on actinide metals, clarifying their coupling schemes and electron delocalization.

Findings

Pu and Am are well described by jj coupling scheme.

Np and Cm require intermediate coupling scheme for accurate description.

Pressure causes band broadening and 5f electron delocalization.

Abstract

Electronic structure of bcc Np, fcc Pu, Am, and Cm pure metals under pressure has been investigated employing the LDA+U method with spin-orbit coupling (LDA+U+SO). Magnetic state of the actinide ions was analyzed in both LS and jj coupling schemes to reveal the applicability of corresponding coupling bases. It was demonstrated that whereas Pu and Am are well described within the jj coupling scheme, Np and Cm can be described appropriately neither in {m-sigma}, nor in {jmj} basis, due to intermediate coupling scheme realizing in these metals that requires some finer treatment. The LDA+U+SO results for the considered transuranium metals reveal bands broadening and gradual 5f electron delocalization under pressure.