Magnetic moment of iron in metallic environments

Citation
Gw. Fernando et al., Magnetic moment of iron in metallic environments, PHYS REV B, 61(1), 2000, pp. 375-381
Citations number
28
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B
ISSN journal
1098-0121 → ACNP
Volume
61
Issue
1
Year of publication
2000
Pages
375 - 381
Database
ISI
SICI code
1098-0121(20000101)61:1<375:MMOIIM>2.0.ZU;2-C
Abstract
Race-earth iron nitrides are emerging as an important class of magnetic mat erials, In certain rare-earth iron compounds, the insertion of small atoms such as nitrogen and boron has resulted in significant changes in the magne tic properties in the form of higher Curie temperatures, enhanced magnetic moments, and stronger anisotropies. In an attempt to understand some of the above, we have focused on two nitride phases of Fe, namely Fe4N (cubic) an d Fe16N2 (tetragonal). For the Fe16N2 phase, the average Fe moment reported by different experimental groups varies over a wide range of values, from 2.3 mu(B), to 3.5 mu(B). We will discuss some of the recent experiments and examine some related theoretical questions with regard to Fe having such a n unusually large moment in a metallic environment, Employing a Hubbard-Sto ner-like model in addition to local-density results, it is shown that an un usually large on-site Coulomb repulsion is necessary if one is to obtain a moment as large as 3.5 mu(B).