Pb9Al2F24 fluoride: Phase transition and electrical characterization of the high-temperature form

Authors
El Omari, M Reau, JM Ravez, J
Citation
M. El Omari et al., Pb9Al2F24 fluoride: Phase transition and electrical characterization of the high-temperature form, PHASE TRAN, 68(2), 1999, pp. 365-381
Citations number
26
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHASE TRANSITIONS
ISSN journal
01411594 → ACNP
Volume
68
Issue
2
Year of publication
1999
Part
A
Pages
365 - 381
Database
ISI
SICI code
0141-1594(1999)68:2<365:PFPTAE>2.0.ZU;2-Y
Abstract
A phase transition at T-r = 365 +/- 10 K is shown for Pb9Al2F24 by high-tem perature X-ray diffraction, microcalorimetric and electrical measurements. The AC conductivity data of Pb9Al2F24 are analyzed in the Z*, M* and epsilo n* formalisms and the conductivity relaxation parameters are determined. Th e high-temperature form of Pb9Al2F24 is characterized by an activation ener gy (Delta E sigma)(h.t). close to that of the (x=0.12) limiting composition of the Pb1-xAlxF2+x solid solution with fluorite-type structure.