Electrical investigation of some fluorides of composition A2MII+MIII+F9by impedance spectroscopy

Autor: K. Taïbp, A. Kerfah, A Guehria-Laı̈doudi, J. M. Réau, Jean Ravez
Rok vydání: 2001
Předmět:
Zdroj: Phase Transitions. 74:521-529
ISSN: 1029-0338
0141-1594
Popis: The ac conductivity of three fluorides of A2MII+ MIII + F9 type, Sr2NiAlF9, Sr2ZnGaF9 and Ba2MnCrF9, between 293 and 773K, has been analyzed within a combined complex impedance and modulus formalism. The antiferroelectric-paraelectric phase transition of Sr2ZnGaF9 has been characterized. A hopping mechanism for charge carriers is suggested for the three materials; their electrical performance are relatively weak. Sr2NiAlF9 and Sr2ZnGaF9 can be considered as ionic conductors of the F- ion. On the contrary, the conductivity in Ba2MnCrF9 is rather of an electronic nature.
Databáze: OpenAIRE