AC electrical properties of the mixed crystal (NH4)3H(SO4)1.42(SeO4)0.58

The frequency dependence of the AC conductivity of (NH4)3H(SO4)1.42(SeO4)0.58 (NHSSe) has been presented in the temperature range (299-393 K). The conductivity data has been analysed in terms of two theoretical models: hopping over a potential barrier model and quantum-tunnelling model. Values of the exponent s, decrease from 1.08 to 0.91 with increasing temperature and the experimental data revel that the hopping model is the rate determining mechanism.