Titre :

Across the Structural Re-Entrant Transition in BaFe2(PO4)2: Influence of the Two-Dimensional Ferromagnetism

Auteur(s) :

David, Rénald [Auteur]
Unité de Catalyse et Chimie du Solide - UMR 8181 [UCCS]
Pautrat, Alain [Auteur]
Laboratoire de cristallographie et sciences des matériaux [CRISMAT]
Filimonov, Dmitry [Auteur]
Lomonosov Moscow State University = Université d'État Lomonossov de Moscou [Moscou] [MSU]
Kabbour, Houria [Auteur]
Unité de Catalyse et de Chimie du Solide (UCCS) - UMR 8181
Vezin, Herve [Auteur]
Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement (LASIRE) - UMR 8516
Whangbo, Myung-Hwan [Auteur]
North Carolina State University [Raleigh] [NC State]
Mentré, Olivier [Auteur]
Unité de Catalyse et Chimie du Solide - UMR 8181 [UCCS]

Titre de la revue :

Journal of the American Chemical Society

Nom court de la revue :

J. Am. Chem. Soc.

Numéro :

135

Pagination :

13023-13029

Éditeur :

American Chemical Society (ACS)

Date de publication :

2013-08-22

ISSN :

1520-5126

Mot(s)-clé(s) en anglais :

Chemical structure
Magnetic properties
Phase transitions
Crystal structure
Lattices

Discipline(s) HAL :

Chimie/Chimie théorique et/ou physique

Résumé en anglais : [en]

BaFe2(PO4)2 was recently prepared by hydrothermal synthesis and identified as the first two-dimensional (2D) Ising ferromagnetic oxide, in which honeycomb layers made up of edge-sharing FeO6 octahedra containing high-spin ...
Lire la suite >BaFe2(PO4)2 was recently prepared by hydrothermal synthesis and identified as the first two-dimensional (2D) Ising ferromagnetic oxide, in which honeycomb layers made up of edge-sharing FeO6 octahedra containing high-spin Fe2+ ions (S = 2) are isolated by PO4 groups and Ba2+ cations. BaFe2(PO4)2 has a trigonal R-3 structure at room temperature but adopts a triclinic P-1 structure below 140 K due to the Jahn–Teller (JT) instability arising from the (t2g)4(eg)2 configuration. The triclinic crystal structure was refined to find significantly distorted Fe2+O6 octahedra in the honeycomb layers while the distortion amplitude QJT was estimated to 0.019 Å. The JT stabilization energy is estimated to be ∼7 meV per formula unit by DFT calculations. Below ∼70 K, very close to the ferromagnetic transition temperature Tc = 65.5 K, the structure of BaFe2(PO4)2 returns to a trigonal R-3 structure in the presence of significant ferromagnetic domains. This rare re-entrant structural transition is accompanied by a discontinuous change in the quadrupolar splitting of Fe2+, as determined by Mössbauer spectroscopy. EPR measurements show the presence of magnetic domains well above Tc , as expected for a ferromagnetic 2D Ising system, and support that the magnetism of BaFe2(PO4)2 is uniaxial (g⊥ = 0).Lire moins >

Langue :

Anglais

Comité de lecture :

Non

Audience :

Internationale

Vulgarisation :

Non

Établissement(s) :

Université de Lille
CNRS

Collections :

• Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement (LASIRE) - UMR 8516

Équipe(s) de recherche :

Propriétés magnéto structurales des matériaux (PMSM)

Date de dépôt :

2021-06-17T14:58:05Z
2021-09-09T17:48:39Z
2021-09-10T10:49:28Z