Dielectric relaxation in double potassium yttrium orthophosphate K3Y(PO4)2 and sodium yttrium orthophosphate Na3Y(PO4)2

This paper presents the results of our investigations on electric properties of double alkali metal yttrium orthophosphates M3IY(PO4)2 (MI = Na, K). Electric permittivity measurements have been performed on polycrystalline samples of potassium yttrium orthophosphate K3Y(PO4)2 and sodium yttrium orthophosphate Na3Y(PO4)2 in the temperature range from −20 °C to +120 °C and frequency range from 1 kHz to 1 MHz. Measurement of the frequency and temperature dependence of dielectric properties give information about dynamical reorientation of molecules with permanent or long lasting induced electric dipole moment μ.