Titre :

Compressibility of structural modulation waves in the chain compounds BaCoX2O7 (X = As, P): a powder study

Auteur(s) :

Das, Ranjana R. [Auteur]
Leclercq, Bastien [Auteur]
Unité de Catalyse et Chimie du Solide - UMR 8181 [UCCS]
Bouvier, Pierre [Auteur]
Arevalo Lopez, Angel [Auteur]
Unité de Catalyse et Chimie du Solide (UCCS) - UMR 8181
Goujon, Céline [Auteur]
Itié, Jean-Paul [Auteur]
Polian, Alain [Auteur]
Mentre, Olivier [Auteur]
Unité de Catalyse et Chimie du Solide (UCCS) - UMR 8181
Unité de Catalyse et Chimie du Solide - UMR 8181 [UCCS]
Colin, Claire V. [Auteur]

Titre de la revue :

Acta Crystallographica Section B : Structural Science, Crystal Engineering and Materials [2014-...]

Nom court de la revue :

Acta Crystallogr B Struct Sci Cryst Eng Mater

Numéro :

78

Pagination :

162-171

Éditeur :

International Union of Crystallography

Date de publication :

2022-04-17

ISSN :

2052-5206

Mot(s)-clé(s) en anglais :

DFT-relaxed structural models
high-pressure X-ray diffraction
high-pressure Raman spectroscopy
first-order structural phase transition
incommensurate structural modulation

Discipline(s) HAL :

Chimie/Cristallographie
Chimie/Chimie inorganique

Résumé en anglais : [en]

BaCoX2O7 (X = As, P) are built on magnetic 1D units in which strong aperiodic undulations originate from incommensurate structural modulations with large atomic displacive amplitudes perpendicular to the chain directions, ...
Lire la suite >BaCoX2O7 (X = As, P) are built on magnetic 1D units in which strong aperiodic undulations originate from incommensurate structural modulations with large atomic displacive amplitudes perpendicular to the chain directions, resulting in very unique multiferroic properties. High-pressure structural and vibrational properties of both compounds have been investigated by synchrotron X-ray powder diffraction and Raman spectroscopy at room temperature and combined with density functional calculations. A structural phase transition is observed at 1.8 GPa and 6.8 GPa in BaCoAs2O7 and BaCoP2O7, respectively. Sharp jumps are observed in their unit-cell volumes and in Raman mode frequencies, thus confirming the first-order nature of their phase transition. These transitions involve the disappearance of the modulation from the ambient-pressure polymorph with clear spectroscopic fingerprints, such as reduction of the number of Raman modes and change of shape on some peaks. The relation between the evolution of the Raman modes along with the structure are presented and supported by density functional theory structural relaxations.Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

Projet ANR :

Couplages Magnéto-Electriques exacerbés dans des matériaux à unités ferromagnétiques

Établissement(s) :

Université de Lille
CNRS
Centrale Lille
ENSCL
Univ. Artois

Collections :

• Unité de Catalyse et Chimie du Solide (UCCS) - UMR 8181

Équipe(s) de recherche :

Matériaux inorganiques, structures, systèmes et propriétés (MISSP)

Date de dépôt :

2023-05-30T15:19:31Z
2023-06-21T09:19:10Z