--------------------
- P-T Phase Diagram of LuFe2O4 doi link

Auteur(s): Poienar Maria, Bourgeois Julie, Martin Christine, Hervieu Maryvonne, Damay François, Garbarino Gaston, Hanfland Michael, Hansen Thomas, Baudelet Francois, Bantignies J.-L., Hermet P., Haines Julien, Rouquette Jérôme

(Article) Publié: Crystals, vol. 8 p.184-1-184-17 (2018)
Texte intégral en Openaccess : openaccess


Ref HAL: hal-01826289_v1
DOI: 10.3390/cryst8050184
WoS: 000435192500003
Exporter : BibTex | endNote
Résumé:

The high-pressure behavior of LuFe2O4 is characterized based on synchrotron X-ray diffraction and neutron diffraction, resistivity measurements, X-ray absorption spectroscopy and infrared spectroscopy studies. The results obtained enabled us to propose a P-T phase diagram. In this study, the low pressure charge-ordering melting could be detected by synchrotron XRD in the P-T space. In addition to the ambient pressure monoclinic C2/m and rhombohedral R(3) over bar m phases, the possible P (1) over bar triclinic phase, the monoclinic high pressure form Pm and metastable modulated monoclinic phases were observed; the latter modulated monoclinic phases were not observed in the present neutron diffraction data. Furthermore, the transition to the Pm phase which was already characterized by strong kinetics is found to be favored at high temperature (373 K). Based on X-ray absorption spectroscopy data the Pm phase, which could be recovered at atmospheric pressure, can be explained by a change in the Fe-local environment from a five-fold coordination to a distorted 5 + 1 one.