GUAN, Shian; ROUGIER, Aline; SUCHOMEL, Matthew; PENIN, Nicolas; BODIANG, Kadiali; GAUDON, Manuel

doi:10.1039/C9DT01241A

Métadonnées

Afficher la notice complète

Licence d’utilisation du document

GUAN, Shian
Institut de Chimie de la Matière Condensée de Bordeaux [ICMCB]

ROUGIER, Aline
Institut de Chimie de la Matière Condensée de Bordeaux [ICMCB]

SUCHOMEL, Matthew
Institut de Chimie de la Matière Condensée de Bordeaux [ICMCB]

Langue

Article de revue

Ce document a été publié dans

Dalton Transactions. 2019-06-25, vol. 48, n° 25, p. 9260-9265

Royal Society of Chemistry

Résumé en anglais

The mechanism of the displacive phase transition in VO2 near the transition temperature is discussed in terms of a geometrical approach, combining simple calculations based on the Brown's band valence model and in situ X-ray diffraction experimental results. Considering that the structural origin is well linked to the electrostatic potential optimization as in a Peierls model, our geometrical calculations and experimental studies are in agreement and suggest that VO2 phase transition is the consequence of very short atomic shifts mainly associated to a decrease of the 2nd sphere coulombic interactions. Hence, at a given temperature, the allotropic form (monoclinic versus rutile form) offering the largest unit-cell volume is stabilized over the lower unit-cell volume allotropic, while the transition occurs at the intercept of the unit cell variation versus temperature of the two forms, which exhibit significantly different thermal expansion coefficients.< Réduire

Métadonnées

Licence d’utilisation du document

Geometric considerations of the monoclinic–rutile structural transition in VO2

Langue

Ce document a été publié dans

Résumé en anglais

DOI

Origine

Unités de recherche