Raman spectra, bond characteristics, and microwave dielectric properties of Gd2Mo3O12 ceramics

Gd2Mo3O12 ceramics were prepared using the traditional solid-phase reaction method. All samples were found to possess an orthorhombic crystal structure with a space group of Pba2, as revealed by refined XRD results. The ceramic sintered at 1000 degrees C exhibited a high relative density of 96.95 % and superior microwave dielectric properties, including er of 9.42 & PLUSMN; 0.05, x f of 49258 & PLUSMN; 1200 GHz, and af of -71.8 & PLUSMN; 0.7 ppm/degrees C. The results suggest a correlation between an increase in er and higher relative density, and a more compact and uniform microstructure can lead to higher x f value. Chemical bonding theories and Raman spectroscopy analysis reveal that Mo-O bonds, rather than Gd-O bonds, dominate the microwave dielectric properties. Furthermore, the er of Gd2Mo3O12 ceramic was closely related to bond ionicity, while x f and af were mainly determined by lattice energy and bond energy, respectively.