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Updated: Jul 19, 2026
12:22
Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films
Published on: November 9, 2015
Emergent magnetic moments produced by self-damage in plutonium
S K McCall1, M J Fluss, B W Chung
1Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550, USA. mccall10@llnl.gov
Summary
Self-damage in plutonium (Pu) creates localized magnetic moments, transforming the previously nonmagnetic metal. Radiation defects induce a temperature-dependent magnetic susceptibility, revealing insights into plutonium's complex electronic structure.
Area of Science:
- Condensed matter physics
- Materials science
- Actinide chemistry
Background:
- Plutonium exhibits a complex phase diagram due to overlapping 5f electron orbitals.
- Pure plutonium lacks experimental evidence for localized magnetic moments, showing Pauli susceptibility instead.
- Radiation damage from alpha decay introduces defects, influencing plutonium's magnetic properties.
Purpose of the Study:
- To investigate the impact of self-induced radiation damage on the magnetic susceptibility of plutonium.
- To understand the behavior of 5f electrons in plutonium under defect-induced conditions.
- To determine if self-damage can induce magnetic moments in nonmagnetic plutonium.
Main Methods:
- Systematic study of temperature-dependent magnetic susceptibility (chi(T)) in alpha-Pu and Ga-stabilized delta-Pu.
- Controlled introduction and freezing of radiation damage below 35 K.
- Analysis using a two-component model incorporating Curie-Weiss and short-range interaction terms.
Main Results:
- Radiation damage significantly increases temperature-dependent magnetic susceptibility in plutonium.
- This damage-induced effect is reversible with thermal annealing above room temperature.
- Below 35 K, damage is stable, allowing systematic study of its magnetic influence.
Conclusions:
- Self-damage in plutonium creates localized magnetic moments, contrary to pure, undamaged material.
- Disorder-induced local moment models explain the observed magnetic behavior.
- Plutonium's magnetic properties are highly sensitive to its defect structure.
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