Designing Pu Intermetallics with First Principle Calculations

TL;DR

This paper combines first-principles calculations and experimental techniques to discover and characterize two new plutonium-based intermetallic compounds, revealing their stability, magnetic order, and electronic properties.

Contribution

It introduces a computational-experimental approach to discover and analyze new Pu intermetallics, specifically PuNiSn and PuPtSn, with detailed characterization.

Findings

PuNiSn and PuPtSn are stable intermetallic compounds.

PuNiSn and PuPtSn exhibit antiferromagnetic order at low temperatures.

PuNiSn shows Kondo behavior, while PuPtSn exhibits crystal field effects.

Abstract

We present the ab initio supported discovery of two new Pu based intermetallic compounds, PuNiSn and PuPtSn. Using density functional theory, the formation energies within the relevant ternary phase diagrams were calculated to predict the stability of both compounds. Simultaneously, Pu-Ni-Sn and Pu-Pt-Sn materials were arc-melted and subsequently characterized with magnetization, specific heat, and resistivity measurements from 2-300 K. Magnetization measurements show that PuNiSn and PuPtSn order antiferromagnetically at TN = 11 K and TN = 15 K, respectively. Specific heat measurements show an enhanced residual electronic specific heat that is indicative of strong electron correlations. Resistivity measurements are indicative of Kondo behavior for PuNiSn while crystal field effects may play a role in the observed temperature dependence for PuPtSn.