Crystal structure, infrared spectra and microwave dielectric properties of novel extra low-temperature fired Eu2Zr3(MoO4)9 ceramics

A new kind of low-temperature fired Eu2Zr3(MoO4)(9) ceramic was fabricated by conventional solid-state reaction method. The mixed powders was calcined at 600 degrees C and the samples were sintered at 500 degrees C -700 degrees C for 4 h. X-ray diffraction analysis and Rietveld refinement indicated that Eu2Zr3(MoO4)(9) belonged to a trigonal system with space group R-3c. Bond ionicity, lattice energy and bond energy of the ceramic were calculated by the complex chemical bond theory. Microwave dielectric properties were determined at microwave frequencies of 9.7-14.7 GHz by a network analyzer. Far infrared spectra indicated the main contribution to polarization for Eu2Zr3(MoO4)(9) ceramics was the absorption of structural phonon oscillation. The ceramic sintered at 600 degrees C for 4 h exhibited the best dielectric properties with a relative permittivity (epsilon(r)) of 10.75, a quality factor (Q.f) of 74,900 GHz and a temperature coefficient of resonance frequency (tau(f)) of -8.88 ppm/degrees C.