Na-23 and Co-59 NMR studies in metallic NaCo2O4

Citation
R. Ray et al., Na-23 and Co-59 NMR studies in metallic NaCo2O4, PHYS ST S-B, 215(1), 1999, pp. 703-707
Citations number
4
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICA STATUS SOLIDI B-BASIC RESEARCH
ISSN journal
03701972 → ACNP
Volume
215
Issue
1
Year of publication
1999
Pages
703 - 707
Database
ISI
SICI code
0370-1972(199909)215:1<703:NACNSI>2.0.ZU;2-4
Abstract
The results of Co-59 NMR studies in the metallic NaCo2O4 system reveal the existence of both diamagnetic Co3+ and magnetic Co4+ ions in the unit cell. Moreover, there are two inequivalent Co3+ ions in the ratio 2:1. The inequ ivalency of the cobalt ions can be explained from the crystallographic stru cture. A qualitative estimation of the electric field gradient at different cobalt and sodium sites has been made by the point charge model. Na-23 NMR performed in the temperature range 300 to 100 K reveals a linear variation of K-iso against chi(d)(T) in the range 220 to 100 K.