Kondo entropy of δ-phase plutonium and its impact on Pu alloy phase diagrams

Abstract

We present a new analysis of the heat capacity of δ-phase Pu-5 at.% Al with a fit using a single-ion Kondo term and a low-temperature Schottky anomaly in addition to the Debye and linear terms. The Kondo and Schottky terms together contribute 1.2 R to the entropy at 300 K. We show how the extra entropy could affect the alloy phase diagrams of δ-phase Pu.

Keywords:

• actinides
• calorimetry
• Kondo effect
• metals

Acknowledgments

We are pleased to thank Prof G. Kotliar and Dr Tongsik Lee for very useful discussions, and we are grateful to an anonymous reviewer for suggesting several significant improvements. This work was supported in part by the Los Alamos National Laboratory under the auspices of the US Department of Energy.