uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
Lattice dynamics and elastic properties of the 4 f electron system: CeN
Show others and affiliations
2011 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 84, no 20, 205135- p.Article in journal (Refereed) Published
Abstract [en]

The electronic structure, structural stability, and lattice dynamics of cerium mononitride are investigated using ab initio density-functional methods involving an effective potential derived from the generalized gradient approximation and without special treatment for the 4 f states. The 4 f states are hence allowed to hop from site to site, without an on-site Hubbard U, and contribute to the bonding, in a picture often referred to as itinerant. It is argued that this picture is appropriate for CeN at low temperatures, while the anomalous thermal expansion observed at elevated temperatures indicates entropy-driven localization of the Ce f electrons, similar to the behavior of elemental cerium. The elastic constants are predicted from the total energy variation of strained crystals and are found to be large, typical for nitrides. The phonon dispersions are calculated showing no soft modes, and the Gruneisen parameter behaves smoothly. The electronic structure is also calculated using the quasiparticle self-consistent GW approximation (where G denotes the Green's function and W denotes the screened interaction). The Fermi surface of CeN is dominated by large egg-shaped electron sheets centered on the X points, which stem from the p-f mixing around the X point. In contrast, assuming localized f electrons leads to a semimetallic picture with small band overlaps around X.

Place, publisher, year, edition, pages
2011. Vol. 84, no 20, 205135- p.
National Category
Physical Sciences
URN: urn:nbn:se:uu:diva-165701DOI: 10.1103/PhysRevB.84.205135ISI: 000297295400004OAI: oai:DiVA.org:uu-165701DiVA: diva2:474485
Available from: 2012-01-09 Created: 2012-01-09 Last updated: 2012-01-09Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Eriksson, Olle
By organisation
Materials Theory
In the same journal
Physical Review B. Condensed Matter and Materials Physics
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 204 hits
ReferencesLink to record
Permanent link

Direct link