Structural and dielectric properties of microwave dielectric materials xBa(Zn1/3Ta2/3)O3 - (1-x)La(Zn1/2Ti1/2)O3

The structural, vibrational and microwave dielectric properties of xBa(Zn_1/3Ta_2/3)O₃ - (1-x)La(Zn_1/2Ti_1/2)O₃ [x = 1, 0.7, 0.5, 0.3 and 0] are investigated. The materials are synthesized by the solid-state reaction technique. The crystal structure of the materials is obtained from the Rietveld refinement of the X-ray diffraction (XRD) profile. All other materials except Ba(Zn_1/3Ta_2/3)O₃ (x = 1) are crystallized in monoclinic P2₁/n symmetry. The crystal structure of Ba(Zn_1/3Ta_2/3)O₃ is trigonal with P-3m1 space group. The vibrational properties of the materials obtained from Raman spectroscopy are correlated with the structural parameters. The microwave dielectric constant ε_r is maximum for x = 0.5 whereas the quality factor Q.f is maximum for x = 1. The effects of vibrational and structural parameters on the microwave dielectric properties are discussed in detail. The dielectric relaxation and the Ac conductivity of the materials are also studied using the alternating current impedance spectroscopy in the frequency range from 50 Hz to 5 MHz.