Radio and microwave frequency relaxations and conductivity in superionic conductor NASICON

Abstract The radio and microwave frequency complex permittivity and conductivity of Na 1 + x Zr 2 Si x P 3 − x O 12 (x≈1.9) ceramics have been studied between -70°C and 170°C. X-band measurments have been performed at room-temperature for x=0.45, 1.35, 1.9, 2, 2.4 and 2.75 compositions as well for LiZr 2 (PO 4 ) 3 . The problems to obtain the true permitivity and conductivity are discussed with emphasis on porosity. The relationship between polarisability, dc and microwave conductivities are considered. Relaxations are assigned.