Thumbnail Image
Non-discoverable
Item

Electronic structure and bonding properties of cobalt oxide in the spinel structure

Chen, J
; 
Wu, X
; 
Selloni, A
Citations
Altmetric:
Genre
Journal Article
Date
2011-06-20
Advisor
Committee member
Group
Department
Subject
cond-mat.mtrl-sci
 cond-mat.mtrl-sci
Permanent link to this record
http://hdl.handle.net/20.500.12613/6034
Collections
Faculty/Researcher Works
Show all metadata
Files
Thumbnail Image
1104.4383v1.pdf
Adobe PDF, 1.22 MB
Research Projects
Organizational Units
Journal Issue
DOI
10.1103/PhysRevB.83.245204
Abstract
The spinel cobalt oxide Co3O4 is a magnetic semiconductor containing cobalt ions in Co2+ and Co3+ oxidation states. We have studied the electronic, magnetic, and bonding properties of Co3O4 using density functional theory (DFT) at the Generalized Gradient Approximation (GGA), GGA+U, and PBE0 hybrid functional levels. The GGA correctly predicts Co3O4 to be a semiconductor but severely underestimates the band gap. The GGA+U band gap (1.96 eV) agrees well with the available experimental value (1.6 eV), whereas the band gap obtained using the PBE0 hybrid functional (3.42 eV) is strongly overestimated. All the employed exchange-correlation functionals predict three unpaired d electrons on the Co2+ ions, in agreement with crystal field theory, but the values of the magnetic moments given by GGA+U and PBE0 are in closer agreement with the experiment than the GGA value, indicating a better description of the cobalt localized d states. Bonding properties are studied by means of maximally localized Wannier functions (MLWFs). We find d-type MLWFs on the cobalt ions, as well as Wannier functions with the character of sp3d bonds between cobalt and oxygen ions. Such hybridized bonding states indicate the presence of a small covalent component in the primarily ionic bonding mechanism of this compound. © 2011 American Physical Society.
Description
Citation
Citation to related work
American Physical Society (APS)
Has part
Physical Review B - Condensed Matter and Materials Physics
ADA compliance
For Americans with Disabilities Act (ADA) accommodation, including help with reading this content, please contact scholarshare@temple.edu
Embedded videos