Phase transitions in CsHSO4 up to 2.5GPa: Impedance spectroscopy under pressure

Nikolai Bagdassarov (1)

1 Goethe University Frankfurt

Phase transitions in CsHSO4 at pressures up to 2.5GPa have been studied with the help of electrical impedance measurements. The phase boundaries have been identified with the help of calculated activation energies of electrical conductivity and dielectric relaxation time. The derived temperatures of phase transition from the low conductive phase II into super ionic phase I at pressure less than 1GPa confirm the previous results of Ponyatovskiy et al. (1985) and Friesel et al. (1989). The phase diagram derived in this study for pressure larger than 1GPa differs from the data of Ponyatovskiy et al. (1985). The phase transitions IV-VI and VI-I occur at higher temperatures having significantly larger Clapeyron slope. The phase VII was not identified from heating cycle and appears only under cooling between phase I and phase VI. The phase VIII was detected at 2.5GPa at T< 350K and only during heating.

Mots clés: Ionic conductivity; CsHSO4; Phase transitions; Impedance spectroscopy

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Nikolai Bagdassarov. Phase transitions in CsHSO4 up to 2.5GPa: Impedance spectroscopy under pressure. Journal of Physics and Chemistry of Solids, 2011, 72 (4), pp.236. ⟨10.1016/j.jpcs.2011.01.008⟩. ⟨hal-00727163⟩