Density functional theory calculations on magnetic properties of actinide compounds

TL;DR

This study uses density functional theory with Hubbard correction to analyze magnetic structures and electronic properties of actinide compounds UO2, PuO2, and UN, revealing the lowest energy magnetic configuration for UO2.

Contribution

It provides detailed insights into the magnetic ordering and electronic structures of actinide oxides using DFT+U, identifying the 3-k magnetic structure as lowest in energy for UO2.

Findings

UO2 favors a 3-k magnetic structure at U=4.6 eV.

UN and PuO2 do not exhibit rhombohedral distortion or complex 3-k magnetic structures.

The study confirms the magnetic ground state of UO2 aligns with experimental observations.

Abstract

We have performed a detailed analysis of the magnetic (collinear and noncollinear) order and atomic and the electron structures of UO2, PuO2 and UN on the basis of density functional theory with the Hubbard electron correlation correction (DFT+U). We have shown that the 3-k magnetic structure of UO2 is the lowest in energy for the Hubbard parameter value of U=4.6 eV (and J=0.5 eV) consistent with experiments when Dudarev's formalism is used. In contrast to UO2, UN and PuO2 show no trend for a distortion towards rhombohedral structure and, thus, no complex 3-k magnetic structure is to be anticipated in these materials.