Unknown

Dataset Information

0

Phase stabilization by electronic entropy in plutonium.


ABSTRACT: Plutonium metal undergoes an anomalously large 25% collapse in volume from its largest volume ? phase (?-Pu) to its low temperature ? phase, yet the underlying thermodynamic mechanism has largely remained a mystery. Here we use magnetostriction measurements to isolate a previously hidden yet substantial electronic contribution to the entropy of ?-Pu, which we show to be crucial for the stabilization of this phase. The entropy originates from two competing instabilities of the 5f-electron shell, which we show to drive the volume of Pu in opposing directions, depending on the temperature and volume. Using calorimetry measurements, we establish a robust thermodynamic connection between the two excitation energies, the atomic volume, and the previously reported excess entropy of ?-Pu at elevated temperatures.

SUBMITTER: Harrison N 

PROVIDER: S-EPMC6639308 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

altmetric image

Publications

Phase stabilization by electronic entropy in plutonium.

Harrison N N   Betts J B JB   Wartenbe M R MR   Balakirev F F FF   Richmond S S   Jaime M M   Tobash P H PH  

Nature communications 20190718 1


Plutonium metal undergoes an anomalously large 25% collapse in volume from its largest volume δ phase (δ-Pu) to its low temperature α phase, yet the underlying thermodynamic mechanism has largely remained a mystery. Here we use magnetostriction measurements to isolate a previously hidden yet substantial electronic contribution to the entropy of δ-Pu, which we show to be crucial for the stabilization of this phase. The entropy originates from two competing instabilities of the 5f-electron shell,  ...[more]

Similar Datasets

| S-EPMC6900038 | biostudies-literature
| S-EPMC2474475 | biostudies-literature
| S-EPMC9443449 | biostudies-literature
| S-EPMC3696814 | biostudies-literature
| S-EPMC8991010 | biostudies-literature
| S-EPMC6820750 | biostudies-literature
| S-EPMC10199023 | biostudies-literature
| S-EPMC9581490 | biostudies-literature
| S-EPMC5561097 | biostudies-literature