Dielectric anomalies above the glass transition in the mixed K_1-X(NH₄)_XH₂PO₄ crystals

Abstract

The temperature dependences of the complex dielectric constant have been measured in the mixed K_1-x(NH₄)_xH₂PO₄ crystals at frequencies 10Hz-100kHz. For ammonium concentrations 0.3 ≤ x ≤ 0.6 pronounced dielectric anomalies in c-direction has been detected in the temperature range 200–260K. It was found that in this temperature range the dielectric relaxation dispersion is changed dramatically.