skip to main content

DOE PAGESDOE PAGES

This content will become publicly available on September 21, 2018

Title: Pressure-driven insulator-metal transition in cubic phase UO 2

Understanding the electronic properties of actinide oxides under pressure poses a great challenge for experimental and theoretical studies. Here, we investigate the electronic structure of cubic phase uranium dioxide at different volumes using a combination of density functional theory and dynamical mean-field theory. The ab initio calculations predict an orbital-selective insulator-metal transition at a moderate pressure of ~45 GPa. At this pressure the uranium's 5f 5/2 state becomes metallic, while the 5f 7/2 state remains insulating up to about 60 GPa. In the metallic state, we observe a rapid decrease of the 5f occupation and total angular momentum with pressure. Simultaneously, the so-called "Zhang-Rice state", which is of predominantly 5f 5/2 character, quickly disappears after the transition into the metallic phase.
Authors:
 [1] ;  [2] ;  [3]
  1. Science and Technology on Surface Physics and Chemistry Lab. Mianyang (China)
  2. Brookhaven National Lab. (BNL), Upton, NY (United States)
  3. Univ. of Fribourg (Switzerland)
Publication Date:
Report Number(s):
BNL-200058-2018-JAAM
Journal ID: ISSN 0295-5075
Grant/Contract Number:
SC0012704
Type:
Accepted Manuscript
Journal Name:
Europhysics Letters
Additional Journal Information:
Journal Volume: 119; Journal Issue: 5; Journal ID: ISSN 0295-5075
Publisher:
IOP Publishing
Research Org:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY
OSTI Identifier:
1425058