Conductivity and dielectric studies in Rb2SeO4.Te(OH)6
H. Litaiem*, M. Dammak, T. Mhiri, A. Daoud
Laboratoire de L’Etat Solide (L.E.S), Faculté des Sciences de Sfax, Route de Soukra. 3000
* Corresponding author. E-mail : email@example.com
Received: 16 January 2008; revised version accepted: 29 April 2008
Single crystals of the rubidium selenate tellurate Rb2SeO4.Te(OH)6 (RbSeTe) were obtained by slow evaporation at 300K. Thermal analysis of the title compound show three distinct endothermic peaks at 430, 470 and 490K. Samples were examined by impedance and modulus spectroscopy techniques. The dielectric constant evolution as function of frequency and temperature revealed one anomaly at about 470K attributed to a ferro-paraelectric phase transition. Whereas, the conductivity evolution versus temperature shows the presence of super ionic-protonic phase transition at 490K. The conductivity relaxation parameters associated with the high-disorder protonic conduction have been determined from analysis of the M"/M"max spectrum measured in a wide temperature range.
Keywords: Conductivity; Selenate tellurate; Dielectric.